CONTENTS

Sr.No Topics Page No.

1 Biodiversity of benthic marine algae along the Indian Coast - Rohit M.Oza, Gujarat.

1

2 Seaweed culture in India - N Kaliaperumal, CMFRI Mandapam

5

3 Coastal Vegetation of India and its adaptation during the climate change. - A.G. Untawale

19

4 Algae - invertebrate interaction in marine environment – An ecological approach. - C.U. Rivonkar, Goa University

42

5 Coastal sand dunes of Goa : Comments on evolution and anthropogenic impacts. - Antonio Mascarinhas, NIO Goa

52

6 Ecology of sand dune vegetation. - M. K Janardhanam, Goa University

65

7 Phytoplankton and capacity building. - K.G. Hiremath, Dhempe college Goa.

67

8 Coastal pollution – Status and measures for prevention - X. N. Verlecar, NIO Goa.

75

9 Seaweeds a promising plant of the millennium - V. K. Dhargalkar & Neelam Pareira, NIO, Goa.

87

10 Distribution of marine Cyanobacteria and their Biotechnological potentials - G. Subramanian,NFMC,Bharathidasan Univ. Trichi.

98

11 Life histories and Reproductive Strategies in seaweed - Geetanjali Deshmukhe, CIFE, Mumbai

99

12 Diversity and distribution of calcified algae along the Indian coast - Vijaya Kerkar, Goa. Univ., Goa.

106

13 Association of fungi with marine algae - Seshagiri Raghukumar, NIO, Goa.

108

14 Ecological Re-engineering in Aquaculture : use of seaweed in nutrient stripping - R. A. Shreepada, NIO, Goa.

111

15 Plant tissue culture, its application and prospects. - L.H.Bhonsle, Cosme Pharma Limited,Bicholim.

118

16 Bacterial Association with Marine Vegetation - P.A. Loka Bharathi, NIO,Goa

130

17 Intertidal seaweed ecology - B.B. Chougule, Pune University

141

Biodiversity of Benthic Marine Algae along the Indian coast

Rohit M. Oza* 101, “SARANG” Apartment, Moti Tanki Chowk, Rajkot-360001

Abstract

India is one of the top twelve mega biodiversity countries of the world and

accounts for about 8 % of the global biodiversity though the landmass is only 2.4

% of the World landmass. As we all know that the studies of biodiversity are of

immense economic benefit to the Nations. It involves identification, monitoring,

conservation, sustained and rational use of the bio resources in addition to in situ

conservation. Moreover, studies on biodiversity possess immense economic

interest which dictates in view of regimes of national sovereignty over genetic

resources, patenting life forms and the substantial promises of biotechnology are

quite unprecedented. Involvement of indigenous people and local communities is

yet another important aspect. Now it has been realized that biodiversity is not

only an important resource but also a strength of developing countries, which will

give them tool and strength of bargaining power in International arena. We

recognize that coming into force of International convention on Biological

Diversity in December, 1993 which was ratified by India in February, 1994 and

is a major event of this decade.

___________________________________________________________

• Former Senior Scientist, Marine Algal Discipline, Central Salt & Marine Chemicals Research Institute, Bhavnagar – 364002

CONTENTS 1 Phytoplankton Community Structure and Succession in a Tropical Estuarine

Complex (Central West Coast of India) - V. P. Devassy and J. I. Goes

2 Ecobiology of Marine Cyanobacteria - G. Subramania & N. Thajuddin

3 Marine Microalgal diversity along the Maharastra Coast : Past and Present status - V. K. Dhargalkar, A. G. Untawale and T. G. Jagtap

4 Restoration of Sand Dunes along Human – altered coasts : A Scheme for Miramar beach, Goa. - Antonio Mascariansh

5 Marine pollution in the Indian Ocean - Problems, Prospects & Prospectives. - R. Sen Gupta & S. Y. Sighbal

6 Zoosporic fungal parasites of marine biota - Chandralata Raghukumar

7 Surface morphology of some articulated corallines from India - Vijaya Kerkar and S. D. Iyer

8 Mineralogical studies on calcareous algae - Vijaya Kerkar

2

India has coastline of about 7,500 kilometers, a sizable exclusive economic

zone (2.5 million km-2 ) and a large shelf area (0.13 million km2). EEZ is about two

third area of the mainland. This biogeographically important area harbors variety of

natural resources, flora & fauna widely used for fuel, food and feed in human

welfare. Seaweeds are one of the constituents of these resources, globally used for

phycocolloids and recently for the extraction of drugs intermediate molecules.

In India, seaweed resources are mostly utilized for the production of agar and

alginates. Species of red algae Gracilaria and Gelidiella are principal agarophytes

and species of Sargassum and Turbinaria are the alginophytes utilized by the Indian

seaweed industries. There are about 24 small scale cottage industries producing

agar and 14 sodium alginate producing industries, annually producing about 60-90

tons of agar and 500 tons of sodium alginate. Though Gelidiella as compared to

Gracilaria gives very good quality of agar, its inherent slow growth, restricted

distribution and over exploitation resulted in severe paucity of its natural resources.

The destruction of ecosystems or habitats is the most important cause for the loss of

biodiversity. Recently, World Conservation Monitoring Centre (WCMC) at

Cambridge, UK has warned that unless urgent steps are taken, biological diversity of

immense economic and ecological value may be lost at several locality in India

(Swaminathan,1995). Therefore, there is an urgent need to restore and conserve

this seaweed biodiversity by advocating intelligent resource management measure

such as banning indiscriminate harvesting and augmenting natural resource by

cultivating selected and improved strains of economic seaweeds in Indian waters.

Hence, there is a need for implementation of well conceived and dynamic

strategy on biodiversity estimation of seaweeds of Indian coasts with a view to

develop intelligent management programe for the preservation and conservation of

seaweed resources, their systematic identification, cataloguing and sustainable

utilization.

The recognition and characterization of biodiversity of the benthic marine

algae depends on the work of three scientific discipline. Taxonomy provides the

reference system and depicts the pattern or the tree of diversity of organisms,

3

Genetic gives a direct knowledge of gene variation found within and between the

species. Ecology provides knowledge of varied ecological system in which

taxonomic and genetic diversity is located and provides functional components.

With a view to study biodiversity of benthic marine algal flora of Indian coast,

Oza & Zaidi (2001) made systematic computerized inventories of benthic marine

algal flora of Indian coast. Since the publication of checklist of Indian Marine Algae

by Krishnamurthy and Joshi (1970) and Untawale et al., (1983), a large volume of

new information on Marine Algae were published and scattered. This has

necessitated the need to compile these published taxonomic records on seaweeds

and revise and update the checklist. Literature search was undertaken to list new

records of marine algae reported from Indian waters after 1983. Taxonomic and

systematic changes, together with further new addition, amendments and taxonomic

synonyms are incorporated as far as possible with a view to update in the form of a

systematic inventories. Compilation of these new records show rich biodiversity of

benthic marine flora of Indian coasts represented by total 217 genera and 844

species. Out of these, 136 (62.67%) genera, 434 (51.42%) species belonged to

Rhodophyceae under 16 orders and 30 families; 43 (19.81%) genera, 216 (25.59%)

species belonged to Chlorophyceae under 7 orders and 19 families; 37 (17.05%)

genera 191 (22.63%) species belonged Phaeophyceae under 5 orders and 13

families and 1 genus (100%) and 3 species belonged to Xanthophyceae. Results on

frequency distribution of different genera have shown that in frequency class A (up

to 5 species) represented by 114 (88.44%) genera of red, 34 (76.07%) genera of

green seaweeds and 30 genera (81.08%) of brown seaweeds. In frequency class B

(5 to 10 species) represented by 14 (10.37%) red, 4 (9.30%) green and 3 (8.10%)

brown seaweeds. Three (2.22%) genera of red, 3 (8.10%) genera of brown and 2

(4.5%) of green seaweeds represented frequency class C (11-15 species). In

frequency class D (16-20 species) represented by 2 (1.48%) genera of red and 1

(2.32%) genus of green seaweeds. While in the frequency class E (21-25 species),

F (26-30 species) and G (31-35 species) represented 1 (0.74 %) genus of red, 1 (2.

32%) of green and 1 (0.74%) genus of brown seaweeds respectively. One genus

(2.32%) of green and 1 genus (2.70%) of brown seaweeds recorded highest

4

frequency of class H (above 35 species). Results on these aspects will be presented

and discussed.

Among Indian benthic marine algae, genus Sargassum recorded maximum

number of 57 species and 22 forma and varieties, while genus Gracilaria is the

second highest recording 28 species and 7 varieties and Caulerpa recorded 22

species and 23 varieties and forma. This shows rich biodiversity of industrially

important Indian benthic marine algal flora. Some industrially important genera like

Monostroma, Ahnfeltia, Digenea, Kappaphycus, Palmaria and Pterocladia have

been recorded for the first time in the revised checklist. This will help broaden the

scope for seaweed exploitation for economic gains, especially to derive value added

products. It may be mentioned that CSMCRI has been pioneering Institute in our

country developing viable technologies for extraction of such products from

seaweeds. It is emphasized that numerous other seaweeds can also be of

considerable economic importance for example, Acanthophora spicifera, Grateloupis

indica, Hypnea porphyroides, Laurentia papillosa as source of lambda carrageenan.

Hypnea musciformis and H. valentiae for Kappa carrageenan and Sarconema

filiforme for iota carrageenan . Five species of Porphyra and two species of

Monostrona distributed on Indian coast are also good candidates for exploitation as

supplementary food and Digenea simplex as a source of Kainic acid as anthelminic

drug.Above results depicts rich generic and species diversity of Indian benthic

marine algae, which need immediate attention for implementation of intensive R & D

program inclusive of generic and ecological biodiversity studies with a view to in situ

conservation and regeneration of marine bio resource and their industrial

exploitation and utilization for the socio economic benefits and upliftment of coastal

rural people.

5

SEAWEED CULTURE IN INDIA – PRESENT STATUS AND PROSPECTS N. Kaliaperumal Regional Center of Central Marine Fisheries Research Institute, Marine Fisheries, Ramnad District, Tamil Nadu–623520 INTRODUCTION Seaweeds or marine algae are primitive non-flowering plants without true

root, stem and leaves. They constitute one of the commercially important marine

living renewable resources. They are the only source for the production of

phytochemicals such as agar, carrageenan and algin. Seaweeds are divided into

green, brown, red and bluegreen algae based on the type of pigments, external and

internal structures.

SEAWEED DISTRIBUTION AND RESOURCES

Seaweeds grow in the interdial, shallow and deepwaters of the sea upto 180

m depth and also in estuaries and backwaters. They occur on rocks, dead corals,

stones, pebbles, solid substrata and on other plants. Seaweeds grow abundantly in

south coast of Tamil Nadu, Gujarat coast, Lakshadweep and Andaman – Nicobar

Islands. Luxuriats growth of seaweeds is also found at Mumbai, Ratnagiri, Goa ,

Karwar, Varkala, Vizhinjam, Visakhapatnam, Pulicat lake and Chilka lake. About

271 genera and 1053 species of marine algae belonging to four groups of algae

namely Chlorophyceae, Phaeophyceae, Rhodophyceae and Cyanophyceae have

been recorded so far from Indian waters. The total standing crop of seaweeds from

intertidal and shallow waters of all maritime states and Lakshadweep was estimated

as 91,333 tons ( wet wt ) in an area of 1863 sq. km from Rameswaram (

Dhanushkodi ) to Kanyakumari (Kaliperumal,1994 ; Kaliaperumal et.al., 1998).

SEAWEED USES Seaweeds contain many trace elements, minerals, protein, iodine, bromine ,

vitamins and many bioactive substances. Seaweeds are used for the production of

6

phytochemicals such as agar, carrageenan and alginate which are widely employed

as gelling, stabilizing and thickening agents in many industries like food,

confectionary, pharmaceutical, dairy, textile, paper, paint & varnish etc. Agar (China

grass) is manufactured from some red algae like Gelidiella, Gracilaria, Gelidium and

Pterocladia, while carrageenam from red algae viz. Eucheuma, Kappaphycus,

Chondrus, Hypnea and Gigartina. The brown algae such as Sargasssum,

Turbinaria,Laminaria, Undaria, Macrocystis and Ascophyllum yield alginates. Other

chemical products namely mannitol, iodine, laminarin and furcellarin are also

obtained from seaweeds.

Many protein rich edible seaweeds such as Ulva, Enteromorpha, Codium and

Monostroma (green algae), Sargassum, Hydroclathrus, Laminaria, Undaria,

Macrocystis (brown algae); Porphyra, Gracilaria, Eucheuma, Laurencia and

Acanthophora (red algae) are consumed in the form of soup, salad, vegetable and

porridge. The food products like jelly, jam, chocolate, pickle and wafer can also be

manufactured from certain marine algae.

Seaweeds are cheap source of minerals and trace elements. Hence, meal

could be prepared by grinding the cleaned and washed seaweeds. It can be also

mixed with fish meal. Seaweeds are used in different parts of the world as fertilizer

for various land crops. In India, freshly collected and cast ashore seaweeds are used

as manure for coconut plantation either directly or in the form of compost in coastal

areas of Tamil Nadu and Kerala. Seaweed manure has been found superior to farm

yard manure. The high amount of water soluable potash, other minerals and trace

elements present in seaweeds are readily absorbed by plants and control minerals

deficiency diseases. The carbohydrates and other organic matter present in the

marine algae alter the nature of soil and improve the moisture retaining capacity.

The liquid seaweed fertilizer obtained from seaweed extract is used as foliar

spray for inducing faster growth and yield in leafy and fleshy vegetables, fruits,

orchards and horticultural plants. There are several medicineal properties of

seaweeds. Algae rich in iodine such as Asparagopsis taxiformis, Sarconema spp.

can be used for controlling goitre disease caused by enlargement of thyroid glands.

Many bioactive compounds can be obtained from seaweeds. In India, marine algae

7

are used as raw material for manufacture of agar, alginates and liquid seaweed

fertilizer. ( Chennubhotla et.al., 1981; 1987 a , 1987 b, Kaliaperumal et.al., 1987,

1995; Chennubhotla and Kaliaperumal, 1998 ).

SEAWEED CULTURE Need for seaweed culture and its advantages Seaweeds are cultivated for supply of rawmaterials to the seaweed

industries and for their use as human food. In India, seaweeds collected from wild

are used as raw material for the production of agar and alginate. Nearly 25 agar and

10 algin industries are functioning at different places in maritime states such as

Tamilnadu, Kerela and Karnataka. Annually about 5000 tons (dry wt) of

alginophytes, Sargassum spp, Turbinaria spp and Cystoseira trinodis and 500 tons

(dry wt.) of agarophytes Gelidiella acerosa, Gracilaria edulis, G. crassa and G.

foliifera exploited from the natural seaweed beds mostly from south Tamilnadu

coast, are used as raw materials by these industries. These quantities, particularly

agar yielding seaweeds, are inadequate to meet the raw material requirements of

Indian seaweed industries. As a number of seaweed industries are coming up every

year, there is an increasing demand for the raw materials which the existing

resource can not meet (Kalimuthu and Kaliaperumal, 1996). Hence, commercial

scale cultivation of seaweeds is necessary for uninterrupted supply of raw material

to the industries

There are several advantages in the culture of seaweeds. In additions to

continious supply of alga, crop of single species could be maintained continuously.

By adopting scientific breeding and other modern techniques of crop improvement,

the yield and quality of seaweeds could be improved. Further, if seaweed culture is

carried out on large scale, narural beds could be conserved purely for obtaining

seed materials.

8

METHODS OF SEAWEED CULTURE Vegetative propagation method There are two methods for cultivation of seaweeds – one by vegetative

propagation method and the other by reproductive method. In the vegetative

propagation method, the fragments are inserted in the twists of ropes, tied to nylon

twine or polypropylene straw and cultured in the nearshore area of the sea. The

fragments are also cultured by broadcasting them in outdoor ponds and onshore

tanks. The fragment culture method is a simple one and gives quick results.

Different culture techniques such as fixed off bottom culture, floating raft / cage

culture, bottom culture, green – house culture, spray culture, raceways culture and

tissue culture are adopted for cultivation of various economically important

seaweeds in different countries by vegetative propagation method. (Thivy, 1964,

Chennubhotla , et.al 1987 c; 1990; Kaliaperumal, 1993, 2000; Anonymous,1996).

Reproductive Method In this methiod, healthy reproductive plants collected from wild are

transported to the laboratory / nursery and different types of spores such as

swarmers, zoospores, tetraspores, carpospores and monospores are collected on

various substrata like nylon rope, synthetic rope , coir rope , plastic strips

(polypropylene straw / raffia), bamboo splint ladder, cement blocks, coral stones,

etc. The spores on the substrata are cultured into sporelings in the culture room /

hatchery by manipulation of temperature, light and providing nutrient culture media.

Then the substrates containing sporelings / germlings are transferred to the suitable

culture areas in the sea for their further growth to harvestable size plants. This

method is followed for the commercial scale cultivation of edible red alga Porphyra

and green algae Enteromorpha and Monostroma; agar yielding red alga Gracilaria

cylindrica and algin yielding brown algae Laminaria , Udaria and Macrocystis in

foreign countries such as Japan, China, Korea, Taiwan, Malaysia and U.S.A

(Chennubhotla, et.al., 1987 c; Santelices and Doty, 1980; Kaliaperumal,1993). In

this method the spores take more period for their development to harvestable size

9

plants when compared with the growth of fragments in the vegetative propagation

method.

SEAWEED CULTURE IN INDIA With a view to develop suitable technology on commercial scale cultivation

of agarophytes for augmenting supply of raw material to agar industries, since 1964

CMFRI, CSMCRI and other research organizations have attempted experimental

cultivation of agar yielding seaweeds Gelidiella and Gracilaria and also

carrageenophytes and edible seaweeds such as Hypnea, Sargassum, Turbinaria,

Cystoseira, Hormophysa, Caulerpa, Ulva, Enteromorpha and Acanthophora in

different field environments using various culture techniques. These experiments

revealed that Gelidiella acerosa can be successfully cultivated on coral stones and

Gracilaria edulis, Hypnea musciformis, Aconthophora specifera and Enteromorpha

flexuosa on long line ropes and nets. The technoiques developed, areas tested and

proved and results obtained for these five species are given below.

Gelideilla acerosa This agar yielding red alga was cultured successfully on coir rope frames,

nylon ropes nets and coral stones in the inshore water of Gulf of Manner and Palk

Bay near Mandapam. Small fragments obtained from mother plants were inserted in

the twist of the coir ropes, tied at the mesh intersections of nylon rope nets using

nylon twine and seeded twines were wound on the nails fixed to coral stones.

Maximum yield of 2 fold increase over the quantity of seed material after 60 days of

culture period was obtained from coir rope frames and nylon rope nets ands an

annual yield of 33 fold increase on coral stones. (Subbaramaiah et.al., 1975; Patel

et.al. 1986). The CSMCRI has developed technology for commercial scale

cultivation of Gelidiella acreosa by coral stone method.

Gracilaria edulis Cultivation of this agarophyte was carried out in the lagoon of Gulf of

Mannar islands and in the shallow waters of Gulf of Mannar and Palk Bay at

10

Mandapam using coir rope and nets, nylon rope nets and nylon monolines. The

fragments of the plants were directly inserted in the twists of coir ropes and nets, tied

at mesh intersections of nylon rope nets with nylon twine. In these experiments, an

yield of 3.5 kg/m/year was obtained on long line ropes. Maximum yield of 14 fold

increase after 80 days and an average yield of 3 fold increase after 60 days were

obtained on coir ropes and nylon ropes nets. From the experiments conducted in 0.1

ha area of nets, it is estimated that a total quantity of 120 tons ( wet wt.) crop could

be harvested from 1 ha area of nets in a year. These experiments also showed that

Gracilaria edulis could be successfully cultivated on commercial scale throughout

the year in the Gulf of Mannar side and during June to September in Palk Bay side

of Mandapam area. (Raju and Thomas, 1971; Umamaheshwara Rao, 1974;

Krishnamurthy at.al 1975; 1977 Chennubhotla et.al 1978; Kaliaperumal et.al 1996).

Attempt was made during 1990 for the first time to transport Gracilaria edulis

from Krusadai Island ( Mandapam ) and Karvaratti Island ( Lakshadweep ) to

minicoy and cultivate them in the lagoon on long line coir ropes and nets by

vegetative propagation method. Very encouraging results showing maximum of 30

fold increase in yield was obtained after 60 days growth. These experiments proved

that Gracilaria edulis could be very successfully cultivated on commercial scale in

the lagoon of Lakshadweep island during the premonsoon (March to June ) and post

– monsoon ( October to February ) seasons. (Kaliaperumal et.al 1992;

Chennubhotla et.al, 1992 ).

Gracilaria edulis was cultured successfully in fiberglass tanks at outdoor

environment with continious running seawater and aeration. Maximum of 4.75 fold

increase in biomass was obtained after 70 days. This method can be also be

adopted for commercial scale cultivation of Gracilaria edulis after perfection of

technology. Gracilaria edulis was cultivated successfully also by reproductive

method from tetraspores and carpospores. These spores from mature plants were

liberated and settled on cement blocks and other substrates and cultured to

germlings in the laboratory. Thereafter, they were transferred to the sea. The young

plants grew from the germlings after one month of transplantation and they took

another 4 to 5 months to reach harvestable size plants. This technology has been

11

perfected at CMFRI for commerial scale cultivation. (Reeta Jayasankar and

Kaliaperumal,1991).

Hypnea musciformis This carrageenan yielding red alga was cultivated by the CSMCRI in the

lagoon of Krusadai island. Vegetative fragments of the plants were used as seed

material and they were cultured on long line ropes. Four-fold increase in biomass

was obtained after 25 days growth. (Rama Rao et. al., 1985: Rama Rao and

Subbaramaiah, 1986).

Acanthophora spicifera

This carrageenan yielding and edible red alga was cultivated by CMFRI

in the nearshore areas of Hare Island near Mandapam by vegetative propagation

method. Seed materials tied with polypropylene straw (Plastic strip) were fastened to

nylon monolines. 2.6 fold increase in yield was realised after 25 days growth. This

seaweed was also successfully cultivated on nylon rope nets in Mandapam CMFRI

fish farm pound which is connected to the sea through a feeder canal. An yield of 3.6

fold increase after 45 days in the first harvest and more than 2 fold increase after

another one month in the second harvest were obtained. (Kaliaperumal et.al. 1986).

Enteromorpha Flexuosa This edible green alga was cultivated on nets in the intertidal belt at Okha

(Gujarat) by reproductive propagation method using swarmers. Maximum biomass

of 681.24 g fresh and 82.78 g. dry alga per square meter of he nets was obtained

with in six weeks. The favourable period of cultivation was found to be from

December to January. (Ohno et.al., 1981; Oza et.al ., 1985).

Experimental culture of the carrageenam yielding seaweed Kappaphycus

alvarezii was cultivated successfully by vegetative propagation method at Saurastra

and Mandapam region (Mairh et al., 1995; Eswaran et.al., 2002). The same species

was cultured in the nearshore ares of Narakkal (Cochi ) and Calicut. Pilot scale

culture of Kappaphycus alvarezii by Pepsi Co. is going on in the nearshore area of

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Mandapam. Attempts were made to cultur the agarophytes Gracilaria edulis, G.

corticata and G. foliifera in Kerala coast by reproductive and vegetative propagation

methods.

Technology developed for commercial scale cultivation of Gracilaria edulis

Based on the results obtained in the field cultivation of Gracilaria edulis at

Gulf of Manner and Palk Bay near Mandapam, the central Marine Fisheries

Research Institute has evolved a viable technology in 1983 for commercial scale

cultivation of this agar yielding seaweed using coir rope nets (Chennubhotla and

Kaliaperumal, 1983; Kaliaperumal and Ramalingam, 2000). According to this

method, one Kg of seed material would yield on an average 3 Kg/m2 of net after 60

days. The economics of culture of Gracilaria edulis by rope net culture method in

an area of one hectare are given below. About 700 rope nets can be put up in 1 ha.

With an investment of Rs. 1,04,600/- four harvests can be made during a year. A

total of 21 tons (dry wt) of G. edulis could be harvested in the four harvestes which

will fetch Rs.1,26,000/- yielding a net profit of Rs. 21,400/- . The profit will be high

when agar is produced from the cultured seaweed and then marketed.

13

Economics of Gracilaria edulis cultured in one hectare area. ----------------------------------------------------------------------------------------------------------------

Recurring expenditure for 4 crops ( Rs )

Cost of seed material of G. edulis for 7000 kg @ Rs.4/- per Kg. 28,000

Cost of coir nets (700 nos.) of 5 x 2 m size including fabrication 35,000

Charges (700 x Rs.50 =35,000/-)

Cost of casuarinas poles (1260 Nos) of 2,600 1.5m height @ Rws.10/- per pole Wages for laboures at Rs.25/- or 27,000 3 persons including watch and ward duty (360 days * Rs. 75/-)

Miscellaneous expenditure 2,000

--------------

1,04,600

Income

Production rate of 3 Kg/m2 for one ha/700 nets / harvest 21 tonnes

Income in 4 harvests (in fresh weight in a year) 84 tonnes

In terms of dry wt (75% moisture) 21 tonnes

Present market rate of dry G. edulis Rs.6,000 / tonne

Expected income Rs. 1,26,000

Expenditure forharvests Rs.1,04,600

Net profit for 4 crops Rs. 21,400

14

Transfer of Technology of seaweed culture for rural development The technology of cultivation of Gracilaria edulis on coir rope nets was

transferred to the fisherfolk of Mandapam and nearby coastal villages by the Central

Marine Fisheries Research Institute under the Lab-to –land programme of the

Institute during 1978 –1981 and under the Department of Biotechnology sponsored

project during 2000 – 2002. They were also given training in the post – harvest

technology of seaweeds and production of agar by industry method. The Central

Marine Fisheries Research Institute is also conducting every year short – term

training course on “ Seaweed culture, processing and utilization to the interested fish

farmers, seaweed utilisers, private entrepreneurs and State and Central Government

officials.

PROSPECTS So far in India, only experimental scale cultivation of commercially

important seaweeds such as Gelidiella acerosa, Gracilaria edulis, Hypnea

musciform, Acanthophora spicifera and Sargassum spp at different field

environments using various culture techniques of vegetative propagation method

and Sargassum plagiophyllum, Enteromorpha flexuosa, Ulva fasciata and Gracilaria

edulis by reproductive method using spores were carried out successfully. Only in

recent years pilot scale culture of Kappaphycus alvarezii is being carried out by

Pepsi Co. in Mandapam area. The various biotechnological aspects is being applied

for large scale cultivation of Porphyra (Japan, Korea, Taiwan), Undaria (Japan,

Korea), Laminaria (China, Japan), by reproductive propagation method and

Eucheuma and Kappaphycus (Philippines), Gracilaria (Taiwan), Hypnea

(Philippines), Chondrus and Gigartina (Florida) and Caulerpa (Philippines) by

vegetative propagation method can be adopted for the production of commercially

important seaweeds on large scale to meet the raw material need of Indian seaweed

industries and to conserve the natural seaweed resources of Indian waters for using

as seed material for commercial scale cultivation.

The bays and creeks present in the open shore along the east and west

coast, lagoons of coral reefs in the south–east coast of Tamil Nadu, Andaman –

15

Nicobar islands and atolls of Lakshadweep are suitable localities for cultivation of

seaweeds. The commercial scale cultivation of seaweeds may be undertaken in

these areas by the seaweed utilisers and private entrepreneurs availing the financial

assistance from banks and other funding agencies connected with rural

development programmes. Seaweed cultivation on large scale could not only

augment supply of raw material to the net seaweed based industries, but it would

also provide employnment to the people living in the coastal areas of mainland,

Lashadweep and Andaman – Nicobar islands. This would help in improving their

economic status and thus help in rural upliftment.

REFERENCES Anonymous.1996. Report on a regional study and workshop on taxonomy, ecology

and processing of economically important red seaweeds. Food and Agriculture Organization (of the United Nations). Net work of Aquaculture centers in Asia- Pacific , Bangok, Thailand.pp.1-341

Chennubhotla,V.S.K. and N. Kaliaperumal. 1983. Proven Technology 7. Technology

of Cultured seaweed production . Mar. Fish .infor.Serv., T & E. Ser., 54:19 –20

Chennubhotla ,V.S.K , and N.Kaliaperumal. 1998. Seaweeds and their importance. Proc. Of the Workshop National Aquaculture Week. Published by the Aquaculture Foundation of India, Chennai. Pp. 54 – 57. Chennubhotla, V.S.K, N. Kaliaperumal and S. Kalimuthu .1978 Culture of Gracilaia edulis in the inshore waters of Gulf of Mannar ( Mandapam ). Indian J. Fish, 21 (1 & 2):228 – 229. Chennubhotla, V.S.K., N. Kaliaperumal and S. Kalimuthu .1981. Seaweed recipes

and other practical uses of seaweeds. Seafood Export Journal, 13 ( 10 ) : 9 –16.

Chennubhotla , V.S. K., N. Kaliaperumal and S. Kalimuthu . 1987 a. Economically

important Seaweeds. CMFRI Bulletin, 41 : 3 – 19. Chennubhotla, V.S.K., N.,Kaliaperumal and S. Kalimuthu. 1987 b. Commom

seaweed products.CMFRI Bulletins, 41 : 26 – 30. Chennubhotla , V.S.K.., N. Kaliaperumal, S. Kalimuthu, J.R. Ramalingam, M.

Selvaraj and M. Najmuddin.1987 c. Seaweed culture. CMFRI Bulletin, 41:60 –74.

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Chennubhotla, V.S.K, N. Kaliaperumal and M.S. Rajagopalan, 1990. Seaweed

Culture – An Appraisal. CMFRI Bulletin, 44 (Part – 2): 394 – 402. Chennubhotla, V.S.K., P. Kaladharan, N. Kaliaperumal and M.S. Rajgopalan. 1992.

Seasonal variation in production of cultured seaweed Gracilaria edulis (Gmelin)Silva in Minicoy lagoon (Lakshadweep). Seaweed Res.Utiln., 14(2):109 – 113.

Eswaran,K.,P.K Ghosh and O.Pmairh.2002. Experimental field cultivation of

Kappaphycus Alvarezil (Doty) Doty ex. P.Silva at Mandapam region. Seaweed Res.Utiln,24 (1) : 67 – 72.

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of Okha, Gujarat.In Marine Plants ( ed.V. Krishnamurthy ).pp.153 – 166. Patel, J.B., B.V.Gopal, V.R. Nagulan, K.Subbaramaiah and P.C.Thomas. 1986.

Experimental Field cultivation of Gelidiella acerosa at Ervadi in India. Proc. Symp. Coastal Aquaculture (MBAI, Cochin), 4: 1342 :1343.

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(Gmel.)Silva. Bot.Mar., 14 (2) :71 –75. Rama Rao, K. and K. Subbaramaiah. 1986. A technique for the field cultivaqtion of

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area around Mandapam. Curr. Sci., 43 ( 20 ).

19

COASTAL VEGETATION OF INDIA AND ITS ADAPTATION DURING THE CLIMATE CHANGE

Arvind G. Untawale 48, Nirmiti, Sagar Society

Dona Paula, Goa

ABSTRACT

Coastal Zone of India has rich flora such as mangroves,

sand dune vegetation, marine algae, seagrasses and also

phytoplankton. This zone is luxuriant in its biodiversity and

hence it is ecologically and economically important.

The forthcoming Climate is going to influence the coastal

zone and its vegetation by sea level rise and increase in sea

surface temperature.

The paper considers these impacts on coastal vegetation

under different scenarios and suggests remedial measures.

INTRODUCTION :

Indian coast enjoys the typical tropical climatic pattern mainly influenced by

the monsoonal effect. The Indian peninsula is flanked by the Arabian sea on the

west and Bay of Bengal on the east, which are the arms of ‘closed’ Indian Ocean.

There are two unique offshore, oceanic island systems of Andaman – Nicobar and

Lakshadweep atolls. Apart from major and minor estuaries, there are gulfs and

undulated coastline with varying type of geology and geomorphology.

From estuarine regime to the coastal region as well as the subtidal, the

offshore and the deep oceans, there are unique marine living ecosystems with

special structures, functions and biodiversity. These involve from unicellular

20

planktonic organisms, to higher flora and fauna (Dwivedi, 1990; Adams & Wall,

2000). The marine microbes along with their various processes are very important in

the food chain. The marine living ecosystems observed along the Indian coasts are

sand dune vegetation, mangroves, seagrasses, marine algae and planktons

(Falkowski, 2002; Bakus, 1994). The coastal zone is known for its rich biodiversity

and productivity. However, the manmade changes have influenced this coastal zone

affecting its biota. Now the fourth-coming climate change is threatening the coastal

ecosystems.

The ecological impacts of recent climate change to tropical marine

ecosystems have been scientifically proved. The responses of flora and fauna span

an array of ecosystems and organizational hierarchies from the species to the

community levels. Although we are only at an early stage in the projected trends of

global warming, ecological responses to recent climate change are already clearly

visible (Walther et. al. 2002).

These living ecosystems are conspicuously associated with the microbial

flora, acting at various levels and responsible for several important processes. The

marine ecosystems are perhaps the richest in their biodiversity representing from

unicellular organisms like bacteria, plankton to multi-cellular giant animals like

whales as shown in.

Coastal ecosystems stand to be drastically impacted as a result of global

climate warming. Predictions of coastal responses to global warming remain very

speculative. The coastal environment are migrating landward and bringing about

shifts in marginal vegetation and fauna. In each instance, the coastal ecosystem

changes are made more pronounced because of local development along the

landward merging, which hinders the stress and local impact (Kjerfre, et. al., 1994).

I. SAND DUNE ECOSYSTEM

Coastal dunes are made of sand which is piled high by the wind. Sand is the

by-product of weathered rocks from inland regions. These inland rock formations

have been eroded by rain and wind and washed into the rivers that eventually flow

into the ocean. Once in the sea, the sand is shifted up the coast by currents and

21

wave action. Sand on the continental shelf gets shifted around continuously between

the sea-floor, beach and dunes. Wave action deposits the sand containing heavy

minerals onto the beach and thereafter the sand is blown into dunes by the

prevailing onshore winds. Shells, corals and other skeletal fragments provide

sediments to some beaches especially to those in the tropics.

Dune formation : Coastal features are both natural and manmade. Dunes are built of sand,

which is blown inland from the high water and piles up on existing strata. Until they

are vegetated, dunes are constantly growing and shifting. Normal soil-forming

processes do not affect sand dunes very much, and at the outset they are virtually

devoid of nutrients.

Vegetation plays a dominant role in determining the size, shape and stability

of fore dunes. The aerial parts of the vegetation obstruct the wind and absorb wind

energy. Wind velocity near vegetation is thus reduced below that needed for sand

transport and hence the sand deposit around the vegetation. A characteristic of dune

vegetation, particularly the grasses growing under these conditions, is its ability to

produce upright stems and new roots in response to sand covering, if the plants do

not continue to grow more rapidly than the rate of deposition, the arresting action of

the plant ceases. Successive stages of plant growth and sand deposition result in an

increase of width and height of the dunes (Desai and Untawale, 2002).

Dune vegetation is highly adapted to the salt laden winds of the coast, and

maintains the fore dunes by holding the sand already in the dunes, trapping sand

blown up from the beach and aiding in the repair of damage inflicted on the dunes

either by natural phenomena or by human impact. The combination of dune height,

dune shape and intact vegetation creates a protective system, which directs salt-

laden winds upwards and over the dune crest. As a result, salt sensitive vegetation

communities including littoral rainforests can establish in close proximity to the

beach (Untawale, 1980).

22

Classification of sand dune vegetation : Coastal sand dunes along with the vegetation are variously classified by

different scientists throughout the world. One of the oldest classification is given by

Turner, Stella, Carr and Bird (1962). They described 5 well defined zones of

vegetation. The classification given by them is as under :

Zone I – Embryonic Dune : This zone is nearest to the sea and is unvegetated, but

is in the initial stages of formation. Zone II – The Fore Dune : It runs parallel to the first beach ridge and has sand

binding grasses like Spinifex littoreus growing on it. Some herbs and shrubs though

not actually sand binders but from nearby salt marshes and from the next zone are

also included in this region. Zone III – Dune scrub : This is close to the fore dune and is higher than the fore

dunes and forms the main part of the dune. Different types of shrubs grow here. Zone IV – Shrub Woodland : It is a long narrow sandy ridge running parallel and

separated by sand flats.

Zone V – Dune Woodland : This is made up of the stable Sand Dunes with

vegetational community similar to that found in the neighbouring coastal region of

the main land.

Untawale (1994) classifies the sand dune vegetation forming a natural

triangle with the herbaceous pioneer zone at the base, and back shore zone covered

with trees at the apex. This vegetational profile diverts the wind flow upward,

controlling the erosion. On the pioneer zone the herbs with creeping stolon grow. In

the mid-shore zone herbs and shrubs with comparatively deeper root system are

seen to be naturally growing. And further on the backshore, dune trees are found.

This natural vegetation has to be maintained as they successfully utilize the ground

water. Any change in the growth pattern will interfere with the dynamic system of

sand dunes.

23

II. MANGROVE ECOSYSTEM :

Mangroves is very unique tropical intertidal ecosystem. This is a group of

different angiosperm plants which can tolerate salinity and tidal inundation. These

trees favour soft silty clay soil. Because of their dense root system and the seedling

growth, mangroves are known to prevent erosion and increase the accresion or

sedimentation due to ‘flocculation’ effect. For their growth, these trees need

continuous freshwater and sediment flow from the upstream region along with the

nutrients. This open ecosystem can recycle the nutrients, through the process of

decomposition. The mangrove biodiversity is considered to be very high as

compared to other ecosystems (Table 1).

Table 1 : Mangrove biodiversity of India (Untawale et. al., 2000)

I Flora Genera Species 1 Algae 30 47 2 Fungi 40 50 3 Seagrasses 1 2 4 Mangrove flora 41 59 5 Lichens 8 14 II FAUNA 1 Crustaceans 46 82 2 Molluscs 57 88 3 Wood borers 13 24 4 Fishes 70 120 5 Reptiles - Snakes 18 21 - Lizards 3 4 - Turtles 5 5 - Crocodiles 2 2 -

Amphibians 4 8

6 Birds 53 119 7 Mammals 29 34

24

Due to various reasons vast mangrove forests have been deforested and

reclaimed during the last several centauries. The process is still continuing inspite of

the Coastal Zone Regulations, Forest Conservation Act, Wildlife Act .

Mangrove swamps are also considered as the breeding, feeding and nursery

grounds with very high biodiversity. These areas are also scientifically considered

the ‘sinks’ for methene. Being forest in nature, mangroves also use a huge quantity

of CO2 produced by various manmade activities. It is, therefore, essential to protect

and manage this important mangrove ecosystem, which is a connecting link

between the land and the sea.

Several luxuriant mangrove areas have been declared as biosphere reserve,

Wildlife Sanctuary, Mangrove Parks or Protected areas as well as ‘Mangrove

Germplasm Preservation Centers’ at Kalibhanjdia in Orissa.

Large scale mangrove plantation programmes are also taken up along the

coast for protection from erosion and sea level rise. These dense mangrove areas

are also helpful as the Shelter Belt Areas from cyclones. Mangrove belts would also

act as a buffer zone from the predicted sea level rise, increase in temperature,

floods etc. The main impacts of climate change that can be expected to affect

mangrove ecosystems are sea level rise (SLR) and changes in precipitation through

altered sediment budgets (Ellision, 1994) as a consequence of the impacts resulting

from factors such as sea level rise and changes in ecophysiology and community

composition relative to climate change. Mangroves may be prone to damage in

lesser magnitude storms than previously. Mangroves will become far more fragile as

increased research and management activity (Ellision, 1994, UNESCO, 1992). As

the climatic cycle is itself dependent on the astronomical cycle, it has a global

significance and this property renders mangrove palynology very useful for the

reconstructions of the conditions in the past. (Caratini., 1992).

Indian Mangroves :

Mangroves along the Indian coastline were studied earlier by Mathauda

(1957). The total mangrove area was estimated to be 7,00,000 ha by Sidhu (1963).

25

This estimate excludes mangrove areas of Konkan coast, Goa, Karnataka and

Kerala. The Survey of India has estimated mangrove cover of about 6,36,000 ha

based on landsat data of 1987. As per Forest Survey of India (1997) the total

mangrove area of India is 4822 sq. km. The extent of mangrove cover along the east

coast of India was comparatively larger (80%) than the west coast (20%) due to the

terrain and gradual slope as well as the river deltas of Godavari and Bramhaputra

(Blasco, 1975, Untawale, 1984). General distribution of mangrove species depends

on the substratum, salinity and number of tidal inundation.

a. West Coast : Along the west coast of India, mangroves are found growing on the banks of

estuaries, deltas, backwaters, creeks and other protected areas. In all 34 species,

25 genera and 21 families have been reported from the west coast of India

(Untawale, 1987). Of these, 21 species have been reported from Gujarat, 28 from

Maharashtra, 17 from Goa, 18 from Karnataka, 12 from the coast of Kerala and 5

from Lakshadweep group of islands.

The estimated area of the mangroves along the west coast of India was

114,000 ha (Sidhu. 1963). Over the years many mangrove area have been

reclaimed for the developmental purposes. The Rann of Kuchchh and Cochin

backwaters are also considered as mangrove areas without any significant

mangrove vegetation. Similarly, near Kandla, Mundra and Gulf of Khambat

mangroves are found in the degraded conditions. Deltas of Tapti, Narmada,

Dhandar, Mahi and Sabarmati have some growth of mangroves. A typical

succession pattern is normally observed along the intertidal mudflats of the

estuaries.

Gujarat, despite having second largest mangrove coverage of 37,000 ha

display poor assemblage of 12 species. Avicennia marina, A. alba, A. officinalis,

Rhizophora mucronata, Ceriops tagal, B. gymnorhiza, Aegiceros corniculata and

Sonneratia alba are some of the dominant species occurring along the Gujarat

coast. The most dominant being Avicennia marina forming almost pure stand at

many places.

26

The Kori Creek, mouth, along the northernmost west coast along the Sir

Creek of Pakistan, is one of the largest mangrove patch of mangroves along the

west coast of India. This is naturally protected and growing, otherwise the status of

mangroves in Gulf of Kuchchh is generally degrading. Down South Maharashtra

coast has comparatively better mangrove formations, however, the pressure is

continuously increasing on mangroves in and around Mumbai coast, because of

developmental pressures. Goa State has well preserved, although small area of

mangroves. Towards south Karnataka has a few pockets of mangroves, here and

there (Rao, et. al., 1972). Down south along the Kerala coast, where very good

mangroves were reported (Chand Basha, 1992). Mangrove area is fast dwindling

and urgent efforts are needed for large scale mangrove plantation.

b. East coast : About 80% of the total mangrove area from the Indian coast is situated along

the east coast . In all 48 mangrove species have been recorded from the east coast.

The deltaic system of Ganga, Godavari, Mahanadi, Cauvery, Krishna have luxuriant

mangrove forests. Species of Avicennia and Aegiceras from the dominant vegetation

of Godavari, Krishna and Cauvery deltaic systems while, Ceriops decandra and

Sonneratia apetala form the dominant mangrove of Mahanadi delta. The Gangetic

Sunderbans has thick mangrove forest with a total area cover of approximately

4,20,000 ha. About 33 species of mangroves have been reported from this area.

Mangrove species such as Heritiera fomes, Ceriops decandra, Xylocarpus spp.,

Lumnitzera sp., Sonneratia alba, Kandelia candel, Nypa fruticans and Pheonix

paludosa are limited to the Sunderbans. The dense mangroves of Bengal are

dominated by Excoecaria agallocha, Ceriops decandra, Sonneratia apetala,

Avicennia sp., Bruguiera gymnorhiza, Xylocarpus granatum. X. moluccensis,

Aegiceras corniculatum and R. mucronata. While the species of R. mucronata, R.

apiculata, Ceriops tagal, C. decandra, B. gymnorhiza, L. racemosa, S. apetala, A.

ilicifolius, Avicennia officinalis A. marina, E. Agallocha and Acrostichum aureum

have a uniform distribution along the east and west coast of India. Formation of

mudbanks and germination of mangroves to the climate climax condition.

27

The shallow areas under constant influence of tide and freshwater influx, mangrove

species such as N. fruticans, A. routindifolia and P. paludosa showed luxuriant

growth.

The other deltaic area with luxuriant mangrove forests is Mahanadi estuary

with 21,458 ha. The flora of the Mahanadi delta was represented by dominant

species of S. apetala, H. fomes, Aegialites spp., Phoenix paludosa, Acrostichum

aureum, Xylocarpus sp., R. mucronata, B. gymnorhiza, B. caryophylloides, E.

agallocha etc. Although, there is a high floral diversity, the growth was found to be

stunted due to indiscriminate destruction, loss of soil cover, land erosion, degree of

greater salt water penetration and diminishing freshwater.

Bhitarkanika Biosphere Reserve is situated to the north of Mahanadi delta.

This site has largest number of mangrove species with variation in genus Xylocarpus

representing species like X. moluccensis, X. mekongensis and Xylocarpus sp. This

site is the primary center of biodiversity for Heritiera kanikensis and H. fomes and is

being maintained as wildlife sanctuary and reserve forest for variety of bird and

endangered animal species.

Godavari and Krishna estuarine complex have total mangrove area of 20,000

ha and provide thick mangrove cover. The dominant mangrove species present

were R. mucronata, R. conjugata, C. roxburchiana, B. gymnorhiza, L. racemosa, E.

agallocha, A. marina, A. officinalis etc. The Godavari estuary is dominated by

mangrove species such as Avicennia marina, A. officinalis and Sonnaratia apetala.

In all 22 mangroves and their associates are found in this forest. The Coringa

Wildlife Sanctuary is located in this region.

The Tamil Nadu coast is bestowed upon by the two major mangrove

formation, the Pichavaram mangrove with approximate area of 11,000 ha and

Cauvery delta with approximately 2,450 ha. About 20 species of mangroves and

their associates occur at these sites. Three Rhizophora species reported from these

sites were R. apiculata, R. mucronata, and the putative hybrid species of

Rhizophora, A genetic garden has been established at Pichavaram for conservation

of mangrove genetic resources. The conservation measures are being taken to

restore this mangrove area by Annamalai University and State Forest Department.

28

Other areas such as Point Calimer, Rameshwaram and Gulf of Mannar

showed degraded patchy mangrove formations fringing the scattered islands. About

20 mangrove species have been recorded from these areas with Avicennia marina

as the dominant sp. Some pure formations of mangroves like E. agallocha, Ceriops

tagal have also been recorded from the Rameshwaram and Gulf of Mannar Islands

(Blasco, 1975).

The Andaman group of Islands consist of 204 islands covering an area of

6400 sq. km. out of which about 1150 sq. km is covered by mangroves while,

Nicobar group comprised of 22 islands covering the area of 1600 sq. km of which 35

sq. km is covered with mangroves (Blasco, 1975). The mangrove species recorded

from these group of islands were R. apiculata, R. mucronata, Sonneratia caseolaris

in the proximal zone, S. caseolaris, B. gymnorhiza, A. officinalis and Ceriops tagal in

the middle zone and Heritiera littoralis as well as Pandanus sp. in the distal zone.

III. OTHER ECOSYSTEMS : Flora : There are too few data to came to conclusions. However, on the basis of the

available information, it is possible to make predictions about the impacts of

increased CO2 concentrations, temperature and UV-B fluxes. Seagrasses will show

enhanced photosynthetic rates and growth while intertidal macroalgae may not show

enhanced growth as CO2 increases. Interactions between temperature range and

photoperiod can be responsible for excluding species from particular regions of the

world’s oceans. Climate change may well have other effects on the efficiency with

which marine plants use other resources such as N, Fe or Zn (Beardall et. al., 1998).

a. Algae and Seagrasses : The coastal ecosystem provides a good shelter for marine algal growth and

diversified seaweed flora is often observed. Some of the algae, though in minor

scale, are responsible for reef building. There are certain algae that have calcium

carbonate deposition and are known as coralline algae. The role of calcareous algae

is however, less significant in the Indian Ocean than in the Pacific Ocean. Jagtap

(1987) reported 20 m wide algal ridge on the seaward side of Kavaratti and Agathi

Islands of Lakshadweep.

29

The maximum marine algal biodiversity of more than 180 species and 99

genera is reported from Gulf of Mannar and Palk Bay (Umamaheswara Rao, 1972).

Halimeda opuntia contributed to 20 percent of total sampling. Altogether 82 marine

algal species are recorded from the Lakshadweep lagoons with an estimated annual

yield of 3645 - 7598 m tons of fresh weight per year (Subbaramaiah et. al., 1979).

Rhodophycean species were maximum in numbers (39) followed by 33 green and

10 brown algal species. From Andaman and Nicobar Islands, 64 species and 40

genera were reported including 27 Rhodophycean, 21 Chlorophycean and 15

Phacophycean species. Total marine algal biodiversity is shown in Table 2.

Table 2 : Seaweed Resources available along the Indian Coast No. Coastal States Order Family Genera Species Production

(Ton/year)

01 Gujarat 15 42 105 202 100,000 01 Maharashtra 16 40 76 152 20,000 03 Goa 13 29 48 75 2,000 04 Karnataka 12 19 28 39 ~100 05 Kerala 8 10 14 20 ? 06 Lakshadweep

Islands 13 29 51 82 70,000

07 Tamil Nadu 15 45 428 302 90,000 08 Andhra Pradesh 14 29 51 79 ? 09 Orissa 1 2 3 6 ? 10 West Bengal 3 4 5 6 ? 11 Andaman and

Nicobar Islands 8 25 40 64 ?

(Untawale, Dhargalkar and Deshmukhe, 2000)

Palk Bay and the Gulf of Mannar have extensive seagrass beds. Jagtap

(1996) reported 12 species and seven genera of seagrasses from this area. Five

species of seagrasses are reported from the Minicoy lagoon by Untawale and

30

Jagtap (1984). The common genera were Thallasia, Halophila and Cynodocea.

Kavaratti lagoon had luxuriant seagrass growth of Thalassia and Cymodocea.

b. Phytoplankton : Phytoplankton populations are the parts of the marine food chain. Since these

species are capable of floating on the surface water and also sometimes vertical

migration, will have very little impact of sea level rise. However, due to increase in

Sea Surface Temperature (SST) and the resultant increase in the nutrient

concentration, there is a possibility of ‘eutrophication’ in certain areas. Due to the

availability of essential environmental conditions and nutrients, the planktonic

species show the phenomenon of ‘eutrophication’. The best example of this is

observed along the west coast, during pre-monsoon, blooms of Trichodesmium

erythraeum – a blue green alga. The euphotic zone of the 200 m water column

shows the presence of several phytoplanktonic species which are unicellular in

nature.

There is sufficient information available on the productivity of phytoplankton in

the Arabian Sea (Radhakrishna et. al., 1978; Qasim, 1982; Bhattarhiri, 1992). Goes

et. al., (1992) studied the distribution and production of phytoplanktons by using

satellite imageries for chlorophyll images along the west coast of India. The intense

cooling in the Gulf of Kuchchh, with high phytoplankton biomass, is an interesting

phenomenon.

The most dominant phytoplankton group is diatoms (80%) followed by

cyanobacteria (7%) and dinoflagellates (6%). The most common were Nitzschia

species such as N. seriata, N. closterium and N. pungens comprising 25% of the

total population. Navicula was common (22%) at only one station (15oN 64o E),

followed by Rhizosolenia spp (10%) and Chaetoceros (9%). Ceratium sp. and

Peridinium sp. were the dinoflagellates constituting 4% of the population.

There is no systematic list of phytoplankton species available and most of the

work carried out is site specific. It is necessary to document all available

phytoplankton species systematically, along with the important environmental

31

parameters. It would be worthwhile to study the impact of climate change, like SST,

etc on the phytoplankton communities, like species distribution productivity etc.

IV. Status of Research on the Impact of Climate Change on Marine Ecosystems i. Impact on Marine Ecosystems :

Rapid review of the available literature on the marine ecosystems along the

Indian coast prior to 1990 shows that maximum work on the estuarine, nearshore,

coastal and offshore ecosystems is available on some aspects of biology, ecology,

biochemistry, reproductive biology, qualitative and quantitative distribution as well as

taxonomy.

The concept of climate change is of recent origin. However, some of the

geological publications have significantly contributed to the past climate change and

impact on the Indian coast (Vaidyanadhan, 1991). Several scientific papers have

been published on impact of sea level rise on the coastal environments, in a book

edited by G. Victor Rajamanickam (1990). Untawale & Jagtap, (1991) have reported

the fomation of mudbkanks, deltaic Islands and the growth of mangroves to ‘climatic

climax’ to stabilize the systems in major deltas like Sunderbans. The recent

publication on Climate Change in India ( Shukla, et al., 2002) deals in greater details

about the Indian scenario related with various aspects like past and present

circumstances, model projections, mitigations, forests, food securities, sustainable

developments and future strategies.

There are numerous publications on the marine biology of Indian coasts.

However, very few directly relate to the climate change or its resultant impact. These

contributions, however, could be used for estimating the impact and also to identify

the gaps in information for deciding future line of action. Recently more emphasis

has been given on the ‘Biodiversity’ studies (Untawale et. al., 2000).

Communities of plants living in coastal areas are adapted not only to the

mean sea level but to the regular short term changes or variability in sea level which

are associated with the tidal cycle and recurring seasonal changes. It is, therefore,

necessary to study the impact of climate change like sea level rise and increase in

temperature on marine ecosystems keeping in view their structure and function.

32

It has been argued that even in the case of infrequent episodic events the

communities concerned are disturbance adapted and that indeed disturbance may

be necessary to maintain the biodiversity of some mangrove communities. Such

policies should be designed to address present problems in coastal zones with a

view to strengthening the natural capacity of coastal systems to respond to changes.

At present the scientific consensus seems to suggest that global mean

surface temperature has risen by around 0.6+/-0.2o Cover the last century and that

global mean surface temperature will rise by around 2.5oC by the year 2050 perhaps

reaching 4oC by 2100. It is to be expected therefore that direct effects upon the

productivity of coastal biological communities will occur with some changes in

species distribution and composition.

There is a need for a coordinated and multi-disciplinary approach to impact

assessment rather than a narrow sectoral approach. Potential impacts may be

directly related to temperature and other components of climate.

Secondary impacts in coastal areas resulting from the rise in global mean

temperature will include changes in relative humidity; runoff and river flow rates;

coastal soils and soil fertility; salinity and coastal water chemistry; the distribution,

intensity and possibly also the frequency of storms and coastal flooding.

Such changes will affect coastal vegetation distribution and abundance which

will in turn alter animal distribution as well as abundance and the overall productivity

of natural and agricultural systems on land. Such changes will also affect human

drinking water supplies and require changes in freshwater management practices. In

addition these changes will alter coastal water salinity and mixing which will change

coastal marine ecosystems. All of which will have varying social and economic

impacts in different areas.

iv. Sea level rise

Recent trends in sea level rise suggest that the current average rate of rise is

approximately1.5mm yr-1 and the latest IPCC projections of future global warming

33

suggest that this rate is likely to increase such that global sea level will rise by some

28 cm+/-14 cm by the year 2050. Global sea level rise threatens not only the natural

environments of coastal areas but also low-lying human populations centers along

the Indian coasts.

Frequency of coastal flooding would be increased by arise in sea level, but

would also be changed by alternations to coastal current regimes affecting wave

climates, by changed storm patterns and by changes in rainfall which might enhance

river based flooding in major river systems. It has been suggested that a general

worldwide increase in inundation is expected during the next centaury. Mangrove

ecosystem can function as a buffer zone. With the sea level rise (SLR) mangroves

can gradually migrate towards landward side.

For many coastal cities reliant at the present time on groundwater supplies,

increasing sea levels will restrict the volumes of available freshwater and saline

intrusion will increase. Such changes may result in changes to coastal vegetation. At

present this is being experienced in many coastal areas of India during summer.

The widespread conversion of mangrove ecosystems to other uses such as

mariculture or paddy rice production seriously reduces coastal protection against

storm and wave erosion and reduces the rate of sediment accretion in coastal areas.

Kerala has reclaimed several mangrove areas for paddy and coconut plantation. In

such areas the soils have become acid sulfate and yield has reduced. Moreover,

these areas have become more prone to inundation. Kharland development activity

of Konkan (Maharashtra) has constructed several bunds across the creeks killing

mangroves and resulting into floods.

Continued protection is the only available alternative to such areas of low

levels country. Ultimately the economic costs of continued raising of protective

structures and pumping of water may outweigh the economic benefits which can be

derived from continued use of the land concerned.

The consequences of sea level rise are more likely to be experienced by India

and may include : increased frequency and extent of flooding; rearrangement of

unconsolidated coastal sediments and soils; increased soil salinity in areas

34

previously unaffected; changes wave climates; accelerated dune and beach erosion

and wetland vegetation. As a consequence of the primary impacts a variety of

secondary impacts can be identified which changes in marine primary production.

Changes in marine primary production will affect energy flow to and standing

stocks of higher tropic levels. Such changes will alter the economic viability of living

resource based activities by affecting commercially important species. Changes in

the salinity of coastal wetlands may also alter the distributions of human disease

vectors hence changing the epidemiology of vector borne diseases like malaria.

In many coastal areas current economic and social activities are exacerbating an

already critical situation. Potential impacts of climatic change and sea level rise are

overshadowed in many areas by existing environmental problems and current,

environmentally unsound development practices will increase susceptibility to

predicted global climatic change impacts. Some coastal states are particularly

vulnerable, for example between eight and ten million people live within one metre

above sea level in each of the unprotected deltas and coastal areas like Sunderbans

and Orissa. It is well known fact that every year Bay of Bengal experiences number

of cyclones and floods in major rivers. Mangrove forests which are in good condition,

protect the human life and properties from cyclones and flood. The impact of super-

cyclone of Orissa on mangrove and non-mangrove regions have once again proved

the significance of mangroves and shelter belts (Untawale. 2001).

The economic costs of coastal protection and water regulation may be

prohibitive for India. Alternative strategies which maximize the natural protection

afforded by ecosystems such as mangrove forests and enhance the natural rate of

sediment deposition may be the only possible mechanisms for mitigrating the

potential impacts of rising sea level (Mahtab, 1991).

V. PROTECTION OF THE COASTAL ZONE

The Coastal Zone, i.e. from the Supratidal region to the Infratidal and subtidal

region is very productive, dynamic and sensitive part of the marine system. In

35

addition this zone has perhaps the highest marine biodiversity. There are various

marine living ecosystems like sand dune vegetation, mangroves corals, benthic as

well as associated marine biota.

During the forthcoming Climate Change the coastal zone would be

affected gradually. In view of these adverse effects, it would be essential to

protect this coastal systems. Recently such areas have become the centers of

urban developments. Several important industries, hotels, housing complexes,

slums and other development like ports etc have been developed near the coast

and along the major estuaries. Hence such areas have become major centers of

socio-economic developments at the cost of billions of rupees. In view of this

Govt. of India, keeping in view these environmental, ecological, social and

economical changes has taken several measures for the sustainable

development, conservation and management of the coastal zone and its

sensitive ecosystems.

I. There are several areas, with luxuriant marine flora and fauna along the Indian

coasts, which have been declared as protected under different categories as

follows :

a. Marine Biosphere Reserves

b. Marine Wildlife Sanctuaries

c. Marine Parks

d. Protected Areas

e. Genetic Resource Centers

Table 2 gives a list of a few such areas protected in different coastal states.

In addition to these protective measures, Ministry of Environments & Forests,

Govt. of India, taking into consideration the future climate changes followed by sea

level rise etc. as well as the growing population pressure on the coastal zone,

declared a stretch of 500 m coastal belt all along Indian as the COASTAL

REGULATION ZONE as follows :

36

The intertidal region (area between the Lowest Low Tide to Highest High Tide

Line) and 500m beyond the high tide line is considered the Coastal Regulation Zone

(1991). The first 200m from the HTL, is considered No Development Zone, while

other 300m may be considered for restricted developments.

There are, however, various categories under the coastal zone for protection as follows : II. CRZ-I : This is very important category of the coastal zone and strictly protects all

the sensitive Coastal/Marine Living Ecosystems like Sand dune vegetation,

Mangroves and Corals. These ecosystems naturally protect the coastal zone from

the storms, surges, waves, wind etc. So all these marine ecosystems along the

coast of India (alongwith the two major groups of Islands) have been fully protected.

Other categories II and III are related to the partially developed or relatively

undisturbed coastal areas category IV protects the major and minor Island groups

along the coasts or in the offshore regions.

Ministry of Environment and Forests, Govt. of India is a nodal agency for

implementing the CRZ rules. There are Coastal Zone Management Authorities in

each coastal states and also at the center.

In addition to the conservation and management of the sensitive coastal zone

the Ministry of Environment and Forests, Govt. of India also spends sizable amount

on the implementation of Management Action Plans (MAPS). Table 3 indicates the

funds distributed for various states during the 9th Five Year Plan (1997 to 2002) for

management of mangroves and coral reefs.

Conservation Policies : Policies should be designed to address problems in coastal zones with a view

to strengthening the natural capacity of coastal ecosystems in respond to changes.

In simple terms a dead coral reef cannot grow, while a healthy reef has the potential

to grow and provide continued protection against rising sea levels (Fig. 8). Policies

designed to halt reef degradations or restore damaged reef ecosystems maximize

the potential for reefs to respond to climate change and sea level rise. In addition

such policies provide for the sustainable use of the renewable living resources of

37

reef ecosystems and hence even in the absence of climate change such policies

would provide benefit to future generations (Pernetta and Elder, 1992, 1993).

VI. CONCLUSIONS :

1. The marine ecosystems are living and grow at some definite rate under given

optimum environmental conditions in the coastal region.

2. The climate change is likely to influence the atmosphere and sea

temperature, cyclones, precipitation, floods, coastal erosion and accresion,

sea level rise and the changes in the marine environmental conditions.

3. At the same time the manmade changes in the upstream and the coastal

areas like deforestation, reclamation, pollution, extensive human habitation in

the coastal region and its alteration have already created some unwanted

environmental imbalance, which have started showing their effects and in

future scenarios of further change in the climate, it will have cumulative

impact. There are different scenarios one can imagine as a result of climate

change. These may be of extreme, medium or low impact because there are

several factors and complicated interactions, which may or may not be

visualized as on today.

4. The existing levels of the sea in the coastal and estuarine areas are likely to

shift gradually towards the land, particularly in the low lying areas, during the

sea level rise, giving enough time for the biological organisms to prepare new

habitats for their survival, hence minimum or no loss of biodiversity is

predicted.

5. The marine biological diversity of the littoral region in the tropics, is capable of

tolerating temperature variations and hence normally these organisms may

not be affected much by minor change in water temperature. However, the

subtidal and the planktonic organisms, corals and sensitive benthic forms

might show the adverse impact resulting into mortality or bleaching.

6. Considering the worst scenario of extreme impact on the coastal area, it is

strongly recommended that the present CRZ rules of preserving 500 m region

as No Development Zone (particularly the low lying area) should be adhered

38

to strictly. Otherwise in due course it would be a greatest socio-economic loss

to the country.

7. All the marine ecosystems in the coastal areas should be given top priority

and preserved for posterarity. Shelter belt areas should be developed on

sand dunes and mangrove regions with appropriate density and width,

supported by agro-forestry belt of enough dimensions as a buffer zone.

8. Large scale afforestation programme should be taken up on war footing in all

the catchment areas or watershed regions to minimize the erosion which

increases the siltation of estuaries and minimize the water carrying capacity.

9. Long term monitoring of data or sea level rise and increase in SST be taken

up at selected sites.

10. Detailed studies on CO2 absorption by mangroves and as a methane sinks

can be initiated.

ACKNOWLEDGEMENTS I am grateful to all those who have inspired me to focus my attention on this

phenomen of Climate Change and its impact on Marine Living Ecosystems.

I thank Dr. Vinod K. Dhargalkar for inviting me to contribute for the workshop. REFERENCES : Adams, G.A. and D.H. Wall (2000). Biodiversity above and below the surface of soils

and sediments : Linkages and applications for global change, Bioscience, 50 (12) : 1043 – 1048.

Blasco, F. (1975). The Mangroves of India, French Inst. Pondicherry, Trav. Sec. Sci.

Tech., 14 : 175 pp. Bhattathiri, P.M.A. (1992). Primary production of tropical marine ecosystems, In

‘Ecology and Management’ (eds. K.P. Singh and J.P. Singh) Wiley Eastern Ltd., 269-276.

Bakus, G.E. (1994). CORAL REEF ECOSYSTEMS, Oxford and IBH Publishing Co.

Pvt. Ltd., New Delhi, 232 pp.

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Beardall, J. Beer, S. and Raven, J.A. (1998). Biodiversity of marine plants in an era of Climatic change : Some predictions based on physiological performance, Bot. Mar., 41(1): 113-123.

Caratini, C. (1992). Mangrove pollen in marine quaternary sediments : Marker of

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Chand Basha, S. (1992). Mangroves of Kerala – A fast disappearing asset, Indian

Forester, 175-189. Dwivedi, S.N. (1990). Biological investigations to understand and mitigate the effects

of global warming and sea level rise, In ‘Sea Level Variation and its Impact on Coastal Environment (ed. Rajamanickam), 31-51.

Desai, K. N. and A.G. Untawale (2002). SAND DUNE VEGETATION OF GOA :

CONSERVATION AND MANAGEMENT, Published by Bot. Soc. Goa, 101 pp.

Ellison, J.C. (1994). Climatic change and sea level rise impacts on mangrove

ecosystems, Impacts of Climatic Change on Ecosystems and Species, Marine and Coastal Ecosystems, WWF for Nature, Gland (Switzerland), E.P.A., Washington, D.C. U.S.A. 11-30.

Falkowski, P.G. (2002). The ocean’s invisible forest, Sci. American, 287 (2) : 54-61. Goes, J.I.; H. do R. Gomes; A. Gouveia; V.P. Devassy; A.H. Parulekar and L.V.G.

Rao (1992). Satellite and ship studies of phytoplankton along the West coast of India, In ‘Oceanography of the Indian Ocean’ (ed. B.N. Desai) Oxford and IBH Publi., 67-80.

Jagtap, T.G. (1987). Distribution of algae, seagrasses and coral communities from

Lakshadweep Islands, Eastern Arabian Sea, Indian, J. Mar. Sci., 16 : 256-460.

Jagtap, T.G. (1996). Some quantitative aspects of structural components of

seagrass meadows from South east coast of India, Bot. Mar., 39 : 39-45. Kjerfve, B.; Michener, W.K. and L.R. Goudener (1994). Impacts of Climate change in

estuary and delta environments, In ‘Impacts of Climate Change on Ecosystems and Species : Marine and Coastal Ecosystems, WWF for Nature and EPA, Washington, D.C., Swedish Intern. Develop. Autho. Sto., 31-44.

Mathauda, G.S. (1957). The mangroves of India, In ‘Proc. of the Mangrove Sympos.

Calcutta, Govt. f India, Min. of Food and Agri. 66-87.

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Mahtab, F.U. (1991). Implications of global changes for Bangladesh, In

‘Environmental Implications of Global Change’ IUCN, Gland, 69-92. Pernetta, J.C. and Elder, D.L. (1992). Climate, Sea Level Rise and Coastal Zone :

management and Planning for Global Chnages, Oceans and Coastal Managements, 18 : 113-160.

Pernetta, J.C. and D. Elder (1993). Cross Sectoral, Integrated Coastal Area

Planning : Guidelines and Principles for Coastal Area Developments, A Marine Conservation and Development Report, I.U.C.N. and WWF for Nature, Gland, Switzerland, 63 pp.

Qasim, S.Z. (1982). Oceanography of the northern Arabian Sea, Deep Sea

Research, 29 : 1041 – 1068 Rao, T.A. & A.R.K. Sastry (1972). An ecological approach towards classification of

Coastal Vegetation of India, I – Strand Vegetation, Indian Forester, 98 (10) : 594 – 607.

Radhakrishna, K.; P.M.A. Bhattathiri and V.P. Devassy (1978). Primary productivity

of the Bay of Bengal during August – Sept. 1976, Indian J. Mar. Sci., 7 : 94-98.

Rajamanickam, G. Victor (1990). Sea Level Variations and Its Impact on Coastal

Environment (editor), Tamil University, Thanjavur, 443 pp. Sidhu, S.S. (1963). Studies on mangroves of India, East Godavari Region, Indian

Forester, 89 : 337-351. Subbaramaniah, K; K. Ramarao and M.R.P. Nair (1979). Marine algal resources of

Lakshadweep, Intern. Sympo. Mar. Algae of Indian Ocean Region, Bhavnagar.

Shukla, P.R.; Sharma, S.K. and P.V. Ramana (2002). CLIMATE CHANGE AND

INDIA : Issues Concerns and Opportunities (editors), Tata McGrow Hill, New Delhi, India, 317 pp.

Turner, J.S.; Stella, G.M.; Carr & Bird, E.C.F. (1962). The dune succession at corner

Inlet, Victoria, Proc. Roy. Soc. Victoria, 75 (I) : 7 – 33. Umamaheswara Rao, M. (1972). Ecological observations on some intertidal algae of

Mandam coast, Proc. Indian. Natnl. Sci. Acad., 38 B : 298-307. Untawale, A.G. (1980). Sand dune vegetation of India, In ‘Protection and Control of

Coastal Erosion in India (eds. Braun, P. and B.U. Nayak), Special Publication of NIO, Dona Paula, Goa, 120-134.

41

Untawale, A.G. and T.G., Jagtap (1984). Marine Macrophytes of Minicoy

(Lakshadweep) Coral atoll of the Arabian Sea, Aquatic Bot., 19 : 97-103. Untawale, A.G. (1985). Status of Mangroves in India – A Country Report, In ‘Proc.

Asian Symposium on Mangrove Environment : Research and Management’ UNDP-UNESCO Project Phillipines, 57-74.

Untawale, A.G. (1987). Conservation of Indian Mangroves – A national perspective,

Contribution in Marine Sciences, Dr. S.Z. Qasim Feliciation Volume, 85-104. Untawale, A.G. and T.G. Jagtap, (1991). Floristic composition of the deltaic regions

of India, In ‘Quaternary Deltas of India’ (ed. R. Vaidyanadan), Geological Soc. of India, Memoir 22, 243 –263.

UNESCO (1992). Impacts of expected climate change on Mangroves UNESCO –

UNEP Task Team Report of the 1st Meeting, Rio de Janerio, Rep. Mar. Sci., 61 : 25.

Untawale, A.G.; V.K. Dhargalkar and G.V. Deshmukhe (2000). Prioritization of

potential sites for marine biodiversity conservation in India, In ‘Setting Biodiversity Conservation Priorities For India’, (ed. Singh, Sastry, Mehta & Uppal), WWF for Nature India, Vol. 1, 104-130.

Untawale, A.G. (2001). A Study on the Current Status and Potential of Coastal

Shelter Belts in Western Region, Publishers Agriculture Finance Corporation (NAEDB), Mumbai, 128 pp.

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India (eds.) 291 pp. Walter, G.R.; Post, E.; Convey, P.; Menzel, A.; Permesa, C.; Beebee, T.J.C.;

Fromentin, J.M.; Hoegh-Guldnerg, O. and Bairlein, F. (2002). Ecological responses to recent climate change, NATURE, Vol. 416 (6879) : 389 – 395.

42

Algal – Invertebrate interactions in the Marine environment – An Ecological Approach

C.U.Rivonker Department of Marine Sciences,

Goa University, Taleigao Plateau, 403 206. Email: cur63@yahoo.com; cur63@rediffmail.com

Introduction

Marine environment specifically in the shallow illuminated coastal waters

support large growth of primary producers. These areas are known for its high

productivity mainly due their abundant supply of nutrients from land runoff. On the

other hand these areas being a three dimensional ecosystems, life becomes an

struggle for existence. Hence, it is very imperative that the living communities those

occur in such environments must have some or other type of adaptations or

associations in order to survive and establish themselves in such ecosystems.

Therefore, a large group of plant and animal communities have evolved themselves

so as to enable them to establish in these areas.

In aquatic ecosystems, few areas are known for its high productivity such as

upwelling areas, costal regions, coral reef ecosystems. These regions are known to

have high species diversity, thus leading to an increased competition for the

available limited resources. As a result of such competitive nature there are diverse

and close associations among various species. The type of relations that I am going

to present before you are not predator - prey relations, but those relationships

among unlike species either unharmful to either members or more likely beneficial to

one or both the members - Symbiosis. Such relationships are also found in

terrestrial environments but are well developed in marine environs.

43

Definitions: Symbiosis covers a broad spectrum of associations from random, casual or

facultative associations through more and obligatory groupings that benefit both or

one member to finally those that are parasitic.

Symbiosis is further subdivided into four divisions as follows: 1. Commensalism: This type of relationship is advantageous to one while not

harming the other partner. The partner gaining advantage is referred as commensal

and the other is host.

2. Inquilism: A special division of commensals wherein, the animal lives in the home

made by other or digestive tract without being a parasite.

3. Mutualism: This is a type of relationship wherein, both the partners associate

together for benefit of each other. Here, there are mutual benefits and the partners

are called as symbionts.

4. Parasitism: The relationship wherein, one species lives in or upon another and

draws nourishment from the species at the expense of or to the detriment of other.

Non – parasitic or Symbiotic relations:

The non – parasitic relations do exist among terrestrial communities, however

they are more prominent in marine environments. These are diverse types of

relationships specific to certain groups and species. Most of the symbiotic

relationships in sea among plants and animals are between unicellular algae or their

parts and marine invertebrates. These relations are more prominent in tropical

waters, do exist in temperate waters and are absent in polar waters. Most of the

reports on such relations do exist from areas having high species diversity. In

general, such non - parasitic relations are restricted to shallow sub - tidal or inter -

tidal areas and to upper euphotic pelagic layer.

Types of Associations:

Basically there are two types of associations those are known to occur among

the algae and the benthic invertebrate communities.

44

1. To have entire functional algal cell associated with invertebrate animal.

2. To have only functional chloroplast from algal cell incorporated into tissue of

invertebrate body.

The most prominent algae and invertebrate groups where such relations exist are

given below:

Group Algal taxon Invertebrate taxon

1. Zooxanthellae Dinoflagellates Protozoa, Porifera,

Cnidaria

(Bacillariophyceae) Platyhelmenthes

(Gymnodium microadriaticum) (Convoluta convoluta)

2. Zoochlorella Pyramimonadales Platyhelmenthes

(Fresh water) (Convoluta roscoffensis)

3. Cyanellae Cyanophyceae Porifera and Protozoa

(Trichodina spp)

Most of the algae occur in host and or in the animal. They are known to occur

in vacuoles, individual tissue cells and body spaces within the tissue layers.

Generally, all algal cells are restricted to certain tissues or areas of host where they

grow and reproduce without undergoing digestion by the host. Few invertebrates

incorporate only chloroplast of large algae (Caularpa sp, Codium sp, Cladophora

sp). These chloroplasts are selected and ingested by the invertebrates and are

subsequently transferred to digestive tract or other tissues. Such relations either

cellular or chloroplast are widespread in marine environment among invertebrate

groups (Protozoa, Porifera, Cnidaria, Mollusks).

45

Origin: The exact origin of such relations in marine environment is very difficult to

trace back mainly due to the diverse nature of the living communities. However, the

possible routes those have been suggested are being discussed.

The different phyla outlined above the final phase of digestion in intracellular,

wherein, the individual cells take up the particles from stomach. During this process

ingestion, the cells or chloroplast are picked up by an animal during feeding. These

cells are resistant against the digestive action and or animals lacked enzymes to

break down the plant matter. This forms the basis for a new association, which with

the advent of time turned out to be an obligatory relation for enhanced survival or

selective values.

Distribution and occurrence of algae – invertebrate associations:

The major groups showing such type of relations have been presented below

along with the examples in the marine environment.

Protozoans and Porifera:

In Radiolarians, zooxanthellae are known to occur in the outermost layers.

Other example is of foraminiferan (Globigerina sp is found to be associated with

benthic species (Elphidium sp) and a marine ciliate (Trichodina sp). There are also

reports of sponges being associated with the blue green algae. Such relations are

found to be common in the coral reef areas. Wilkinson (1983) studied the sponges

along the Great Barrier Reef along the Australian coast and stated that 80 % of the

sponges were found to show such relations in the sponges collected from the coral

reef areas.

Cnidaria:

The abovementioned relations are very common in this group especially in

the tropical waters. The tropical shallow water sea anemone, soft corals, sea fans

and stony corals have symbiosis with the zooxanthellae in their tissues (eg. Jelly

fish, Cassiopia sp supports zooxanthellae). In temperate waters incidences are not

46

great though many anemones (Anthopleura sp) retains symbiosis. Among

Ascidians, (Didemnum sp), an unusual prokaryotic unicellular algae called

Prochloron sp having combined features of BGA and GA occurs in the cloacal

system of ascidians.

Ctenophores, Annelids and Echinodermates:

Few symbiotic relations with algal cells are known to occur in Ctenophores (Beroe

sp), Annelida (Eunice sp) and Echinodermata (Ophioglypha sp).

Platyhelmenthes (flatworms), Mollusks and Marine gastropods:

Major type of symbiosis occur in the groups like Platyhelmenthes (Convoluta sp),

mollusks (Tridacna sp) whereas, in marine gastropods, the animal retains only

chloroplast.

Modifications: The symbiotic relations reported from the marine environment have witnessed

a great variety of modifications in both the partners. Such relations have resulted in

anatomical and physiological changes in algal cells as well as the invertebrate hosts.

Algal cells: In Dinoflagellates, the cells loose their flagella, a locomotory organ in this

organisms and thereafter form a characteristic groove around the body and the cell

wall is also reduced in the thickness. A situation worth mentioning is the relation

between Zoochlorellae in Convoluta sp, where the algal cell loose even cell wall and

light sensitive stigmata and occurs in bags containing chloroplast. Studies conducted

on these species of algal cells indicate that if the algal cell is removed from the

organism and are cultured separately, they develop characteristic flagellae, cell wall

and other organs typical to free living forms, thus indicating that the resulting

modifications are due to symbiotic relationship.

Invertebrates:

The relations in the invertebrate groups seem to change with the type of

organism and the degree of interdependence between the partners. The single

47

universal modification in most of the invertebrates that has been reported is that they

occur in the shallow waters where there is adequate light to perform photosynthesis.

Proptozoa and Porifera:

The modifications reported are of low degree wherein, the algae occur as

simple inclusion in the cytoplasm of an animal. In the case of sponges, they

enhance the light gathering ability through morphological flattening thereby

increasing the surface area to intercept the radiant energy.

Cnidaria:

Among this group the definite modifications are reported. The occurrence of

algae is in the inner most layer (endodermis) and reduced tentacle size among those

having high density of zooxanthellae thus highlighting less importance of tentacles to

capture food. In the case of soft coral (family: Xeniidae), the digestive region is

reduced and the animal does not respond to the animal food, whereas in Jelly fish

(Cassiopea sp), behavioral modification is noticed. These species does not swim in

water as others do. They tend to lie upside down on bottom in shallow waters of the

tropical region. Such changes help them to expose their oral arms to light to

illuminate their algae. The oral arms are much expanded and enlarged to provide

more area for habitation of algal cells.

In Platyhelmenthes (Convoluta roscoffensis), an animal living in sandy

beaches and algae (Platymonas convolutae) occurs in surrounding waters have

shown behavioral changes. The C. roscoffensis, lives buried in the upper reaches of

tidal zone. As tide enters, the animal bury and when the tide reseeds, they move to

surface of the sand and spread out and expose their symbionts to light. Thereafter,

when the tide begins to return, the vibrations trigger the re - burrowing response so

that the animals are safely under the sand again before the tidal waters are able to

sweep them off. Another significant aspect that has been reported is that these

48

animals (C. roscoffensis) do not feed as they become adult. If the young worms are

not able to ingest algal symbionts upon hatching mortality occur even if they feed.

Mollusks:

Available reports indicate that there exist about 1000 species of mollusks, 2nd

largest phyla after Arthropods. Among these species only seven are found to have

symbiosis with algal cells. All these species are of bivalve mollusks belonging to

single family i.e. Tridacnidae which include Giant clams. Among the seven species,

six belong to Tridacna and one to Hippopus.

Tridacnid clams inhabit in coral reef areas of the Indo – Pacific region. They

are commonly found in shallow, illuminated waters in tropics. The Giant clam

(Tridacna gigas) is known to measure 1.2 m in length and weighs 263 kg). These

clams occur in tropical waters in an uncharacteristic position. They rest either on

surface of bottom or bore into corals with opening between valves facing up towards

the surface. The valves gape widely and within this opening brightly colored tissue

is seen where symbionts are known to occur. The bright color is mainly due to the

interaction of various pigments deposited, which protects the tissue of clam from the

damaging effect of the light and by providing optimum wavelength to the

zooxanthellae to undertake photosynthesis.

A more remarkable feature is the tremendous change that the body has

undergone from typical clam to accommodate this symbiont association. In case of

normal bivalves, they rest with the foot either embedded in substrate or held against

it. Such position, the hinge is uppermost and will not help tridacnid since it will not

permit tissue and zooxanthellae to be illuminated. Yonge (1975) described that

entire Tridacnid has undergone tremendous rotation with respect to foot such that

hinge comes to rest underside next to foot. This makes the opening of the shell to

face upward. Simultaneously, siphons and siphonal tissue underwent expansion,

grew and extended themselves covering length of upward facing opening, thereby

providing expanded area for occupation of zooxanthellae. During the above

process, one of the muscle was lost. Due to this profound anatomical changes,

tridacnids have markedly different body orientation from other bivalves.

49

Importance of Associations:

The abovementioned associations are very common in the marine

environment among algae and the invertebrates. Further, we have also seen that

these associations are responsible for significant changes in the anatomy and

behavioral changes. Hence, it is imperative that such associations must have

positive values to both the partners.

The corals obtain their food material from zooxanthellae to enhance

calcification process whereas, zooxaxnthellae receive nutrients those are released

by metabolic processes of corals. Most invertebrates having symbiosis with algal

cells maintain integrity and are not digested to obtain nutrients. For example in

zooxanthellae, glycerol an energy yielding compound, which is passed to corals,

whereas the corals release nutrients those are made available to zooxanthellae.

In Sarcoglossan mollusks, Greene (1970) demonstrated that the translocation

of organic molecules derived from chloroplast to animals, however he further stated

that the duration of life of chloroplast appears to be shorter and the animal must

periodically replenish the supply by ingesting the contents of algal cells.

In the case of Giant clam (Tridacna gigas), Frankboner (1971) suggested that

in addition to transfer of nutrients the animals may actively digest the zooxanthellae

cells. In this regard, it is demonstrated that the animal apparently discerns between

the healthy and degenerating cells. Therefore, the clam transports only

degenerating cells from outer mantle blood spaces where they photosynthesize to

deeper tissues where they are consumed by phagocytic blood cells. In this way the

clam retains the symbiotic relationship and at the same time ingest unfit algal cells to

obtain additional nutrients.

In tropical environs, algae benefit the association through access to a larger

and more reliable source of nutrients in the form of metabolic products of the

animals as compared to open waters.

Benthic foraminiferans, the calcification rate is 20 – 100 folds higher among

the symbionts as compared to those without them.

50

Tropical waters contain low dissolved oxygen than temperate waters as water

at higher temperature holds less oxygen. In such areas surface waters especially in

crowded environs produce additional oxygen due to presence of symbiotic algae.

Zooxanthellae gain protection from damage due to intense solar radiation by

living within the tissue of marine invertebrates.

Establishment and transmission of zooxanthellae:

Marine invertebrate must feed on algae to obtain symbiotic chloroplast. The

propagation of symbiotic relationship is accomplished in different ways in different

groups of host. There exist two major routes by which it can be accomplished.

1. Zooxanthellae cells must pass from parents to eggs or larvae eg. Corals, Giant

clam.

2. Each new generation must reinfest itself new algal cell from the surrounding

medium

Among other hosts, propagation of symbiotic relations depend upon

reinfection of each generation. In such cases the invertebrate must obtain the algal

symbiont from the surrounding environment (Protozoa, Porifera – common mode of

transmission). In these groups, each new generation obtains algal cell through

ingestion of free living form of symbionts. Further, among these groups in order to

ensure that the larvae will be infected they have evolved a chemical that attracts

alga to egg cases. As soon as the egg hatches, the hatchling feeds on alga and

under such situation ensures the reinfection. The final possibility of transmission of

symbiont is ingestion of symbiont alga by potential host which is later retained as

symbiotic algal form.

51

Summary:

This lecture presents an overview of the symbiotic relations among the algae

and the invertebrate organisms in the marine environment. The emphasis have been

laid on understanding the ecological approach among the major groups which

display symbiotic relations in the marine environment. Further, the various types of

associations those are common to marine crowded environments have been

discussed. A theoretical approach on the origin of such associations has been

presented. The nature of distribution of algae and invertebrates showing affinity for

such relations, the resulting modifications and the importance of such associations

among different groups of organisms have been discussed. Finally, the various

modes of transmission and establishment have been presented.

References: Greene R W (1970) Symbiosis in Sarcoglossan opisthobranchs: Symbiosis with

algal chloroplas: Translocation of photosynthetic products from chloroplast to host tissue, Malacologia 10 (2): 257 – 380.

Frankboner P V (1971) Intracelluar digestion of symbiotic zooxanthellae by host

aemobocyte in Giant clam (Bivalvia – Tridacnidae) with a note on the nutritional role on the hypertrophied siphonal epidermis, Biol Bull, 141: 222 – 234.

Wilkinson C (1983) Net primary productivity in coral reef sponges, Science, 219:

410 –411. Yonge C M (1975) Giant Clam, Science American, 232: 96 – 105.Cheng T (1971

ed.) Aspects of biology of symbiosis, University Park Press, Baltimore, 327pp.

Wells J W (1957) Coral Reefs In: The treatise on marine ecology and paleoecology,

Geo Soc., Amer., 67, pp 609 – 631

52

COASTAL SAND DUNES OF GOA: COMMENTS ON EVOLUTION AND ANTROPOGENIC IMPACTS

Antonio Mascarenhas National Institute of Oceanography, Dona Paula 403004, Goa.

Introduction

The open sea front of Goa is characterized by a combination of beaches,

rocky shores and headlands that protrude into the sea. Linear sandy beaches are

located between promontories; sandy pockets are often found at the base of

coastal hills. The width of the beaches varies between 50 and 180 meters. Of the

105 km long coast, more than 70 km comprise sandy beaches, all backed by

several rows of 1 to 10 m high sand dunes.

Five key coastal stretches are characterized by prominent sand dune

complexes: Querim - Morjim sector with pristine beaches; Chapora - Sinquerim

belt; Caranzalem - Miramar (Mandovi estuary), the most prominent dune belt

within the estuaries of Goa; Velsao - Mobor linear stretch, the longest strip of

exquisite dunes, and Talpona - Galgibaga strip, presently a pristine area.

The coastal zone of Goa had been exclusively used for agriculture, farming,

shell fishing and traditional fishing. The large plain areas behind the dune belts

were used for farming and paddy cultivation. Recreation was restricted to a few

beaches only. However, since the early 1970’s, the advent of tourism, population

increase, migration towards coasts, building activity and modern societal demands

have resulted in large scale changes in the coastal zone landscape. It is not known

how heavy human activity is affecting the sandy areas in general and the dunes in

particular. This note, a summary of four papers published earlier by this author,

attempts to highlight the importance of coastal sand dunes, their evolution in space

and time and human impacts on this ecosystem.

53

Formation And Evolution Of Coastal Dune Systems The main prerequisites for the formation of sand dunes are wind, sand and

vegetation, three elements with complex and dynamic interactions (see figure).

Wind plays the most important role; its direction, frequency, duration and speed are

to be considered as only winds with a speed greater than 16 km/hour can lift,

displace and transport fine dry sand. This is more so along low gradient beaches

particularly when they are subaerially exposed at low tides, and when strong winds

blow perpendicular to a particular coast.

The vegetation which constitutes inland plants that grow immediately behind

the beaches also play a key role in dune formation since these objects act as wind

breakers due to which wind is forced to drop sand along its path. Vegetation thus

traps and stabilises moving sand. These plants are adapted to an inhospitable

environment characterized by a mobile substrate, saline atmosphere and a regular

bombardment of moving sand.

54

Formation and natural evolution of sand dunes

55

The first step in the formation of a dune, by plants tolerant to salt, is a berm

which is an accumulation of sand brought up by the waves on the beach at a point

just above the highest high tide. These plants flourish with the organic matter

brought by high waves during storms or heavy winds. The berm swells due to the

eolian import of sand. Thus these small sand mounds that form as embryonic

dunes, finally develop into a continuous chain of sand dunes. These eolian

bedforms can be symmetrical, several meters in height and can vary in size from

place to place. Their dimension depend on the degree of evolution and the aptitude

of vegetation to trap and retain sand.

The evolution of a coastal dune system strictly depends on the sedimentary

budget of the beach which refers to the relation between the quantity of sand

brought in by winds and the sand removed by tides and littoral currents. Their

evolution is also dependent on the conditions of the sea level which can be stable,

or in increasing or decreasing mode. Based on the above criteria, four major typical

models can be proposed (see figure):

A. When the sea level decreases, the subaerially exposed beach area

increases; the sand budget is positive and hence the beach progrades and

advances towards the sea. The surplus sand that is available foms a new

sand dune seaward of the existing ones which become stable or inactive as

they are no longer fed by sand. In this way, coast parallel new dune chains

are formed. The inner limits of the new dune strip would signify the

paleoshoreline as the coast advances.

B. When the sea level rises, beaches are flooded due to which they narrow

down and thin out; thus, the sand budget is negative. In such a case there is

hardly any possibility for the formation of new dunes; only a low berm with

minor vegetation is normally found. In such situations, high waves often

wash over the dunes and is accompanied by erosion of the sand body.

C. When the sea level is stable, the sand budget is in a state of equilibrium.

Therefore, the shoreline remains stable and so is the adjacent dune belt with

individual dunes which are broad and high.

56

D. When the sea level shows an increasing tendency, as is the case world over

at present, the sand budget is slightly negative. In such a case, there is a

consequent sediment starvation; high waves and stormy seas force the

shoreline to retreat resulting in a landward migration of the sand dune and

shoreline as well.

The above models depict various stages of sand dune evolution and hence

the evolution of the coastal landscape depending upon the environmental

conditions. However, it is the last model which should generally be applicable at

present, considering the fact that the global sea levels are on the rise. This criteria

has to be considered and be given due importance in the planning and

management of open sea fronts.

Why Are Sand Dunes Needed? Coastal dunes show a dynamic behaviour that has to be to be understood,

respected and not contradicted by anthropogenic influences. Dunes cannot simply

follow a pattern which is not naturally theirs. A sand dune ecosystem has multiple

functions and hence of immense value to coastal populations:

• The beach - dune environment is a highly organized system, the result of a

delicately balanced ecological equilibrium between the forces of the ocean

and loose coastal sediments. Dunes are typical features of coastal stability.

• Sand dunes are eolian bedforms and develop where the transporting

competence of wind is impaired. Vegetated or bare, the dune environment is

classified as edifices of extreme fragility, sensitive and vulnerable due to its

propensity for changes under even slight environmental stress.

• Sand dune chains are categorized as Nature's line of defense. They arrest

blowing sand, deflect wind upwards, assist in the retention of fresh water

and protect the hinterland from attack by waves, cyclones and storm surges

57

and thus obstruct the ingress of saline marine water into the hinterland, and

hence protect the hinterland lowlands from attack by the forces of the ocean.

• Sand dunes are sources of beach nourishment and also neutralize and

dissipate wave and current energy in the coastal zone and hence play a

specific role in maintaining coastal ecological equilibrium by supplying and

restoring sediments lost due to erosion in the coastal zone. Therefore, the

conservation of sand is required to protect coast from erosion and replenish

the loss of sand due to wave and current energies.

• During stormy periods, high waves attack and remove dune sand which then

accumulates on the beach or just beyond the low tide point, in shallow water

in the form of submerged barriers. During calm periods, normal waves return

the same sand back onto the beach where, subsequently, winds blow sand

inland thus reconstituting the dune. Therefore, coastal sand dunes serve as

“sand banks” or security reserves which is extremely essential to maintain

the sedimentary and dynamic equilibrium of the dune - beach ecosystem.

This is because the sand removal and its transfer during storms or by high

waves is a reaction of “self-defence” as the submarine sand barriers force

the wave energy to dissipate earlier and away from the beach and as such

protects the beach from the effects of severe erosion which would not have

been the case otherwise.

• Dune vegetation helps in dune stability. However, it is vulnerable to even

slightest interference due to its fragility. Moreover, sandy stretches including

dune vegetation contain many species of flora and fauna and thus offer an

ecological storehouse due to their rich genetic diversity.

• Sand dunes, especially if covered by dune vegetation which acts as sand

binders, preclude loose sand from advancing inland on the coastal zone,

thus menacing coastal populations and structures.

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• More importantly, the development of tourism has made use of their scenic

beauty; their height gives an unobstructed view of the sea and their peculiar

topography makes them an ideal place for recreation.

• Sand dunes of Goa are about 5000 years old, but can be as old as 6400

years. They formed after the sea level rise almost stabilized in its present

position during Holocene. At places, they are as high as 10 meters as in

Benaulim and Cavelossim.

• Dunes therefore protect the hinterland from winds and other forces and

hence make the zones behind dunes as areas of peace and tranquillity.

Historically, in Goa, areas behind dunes had developed as peaceful areas of

habitation and agriculture, examples that can still be observed at Baga,

Candolim, Caranzalem, Campal, Cansaulim, Colva, Benaulim, Varca and

Cavelossim. For this reason, in several countries of the world, the

conservation of sand dunes is mandatory and development is strictly

regulated.

• The predicted sea level rise is bound to inundate coastal areas and hence

have a profound effect on the coastal zone. Sand dunes stand guard against

any sea level rise consequent upon global warming as they will act as

Nature's wall of defense against the eventual rise in sea levels. Therefore,

these sandy geomorphic edifices have to be preserved.

Human Interference On Sand Dune Belts Some of the major factors responsible for the degradation of coastal sand

dunes of Goa are described below:

1. Impact of constructions / buildings on sand dune fields: Tourism oriented

construction activity and associated infrastructure has led to uncontrolled

growth of many coastal stretches. Several coastal belts are overbuilt. The

59

Baga - Candolim strip is one such example where the coast has turned into

a continuous row of hotels and resorts. As a result, sand dunes have borne

the maximum brunt from anthropogenic pressures. High dunes have been

razed, levelled, flattened or simply removed so as to make place for hotels,

resorts or other structures. Large dune areas are found obliterated due to

human intervention. Excavations and removal of dune sand have created

deficiencies in the volume of sand causing localized erosion.

2. Impact of dune sand extraction: Dune sand deposits have been impacted for

various reasons: (a) the common man uses sand as a cement mixture for

houses, (b) industrialists and builders extract sand which is used for a

variety of major purposes such as buildings, (c) coastal resorts and hotels

located in sandy areas find sand as a readily available resource, (d) leveled

dunes can be converted into plots for further development. The dune sand

extraction has shown many impacts in the form of danger signals: Saline

water destroyed fruit bearing trees at Mobor. In 1977, a dune that was

removed left a gap through which storm winds blew sand onto the fields

affecting paddy output and fruit trees. At Varca, truckloads of sand from

dunes were excavated; the area is now flat and featureless. In 1977 and

1978, storm waves affected Mobor, with inundations in Majorda, Betalbatim,

Varca, Carmona, Cavelossim.

3. Effects of roads on sand dunes: Roads over the dune belts have lead to

obliteration of dune topography, removal of sand, levelling of dunes,

desecration of dune vegetation which acts as sand binders, all of which

generate loose and free sand resulting in its excessive mobility. In all cases

therefore, such roads are covered, sometimes in totality, by a layer of sand.

Such a phenomenon is very evident wherever roads occupy former dune

fields. The Miramar circle can be cited as an example where large quantities

of dry sand are blown inland creating dangerous road conditions for traffic.

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4. Impact of beach shacks: Shacks are supposed to occupy only the upper part

of beaches; however, adjacent sand dunes are often invaded, as seen in

Candolim - Calangute belt. This is where ecological degradation takes place

as dune vegetation is uprooted and cleared to make place for them, an

environmental damage that can sometimes be irreversible. Therefore, beach

shacks, although simple in design, have not only flattened dunes, but have

their own share towards coastal degradation.

5. Influence of recreation on dunes: Activities of pleasure seekers and

picnickers can be observed almost along the entire coast particularly on

sandy stretches. Recreational create ecological degradation in areas which

are most sought and frequented. Driving on the beach, parking of vehicles

on dunes, play fields on dunes, continuous movement by pedestrians and

cyclists are factors which destroy dune vegetation, flatten dunes, induce

shifting of sand and renders the sand mobile, thus affecting the stability of

sand dunes.

6. State of dune vegetation: Dune vegetation is vulnerable to human

interference due to its fragility. Sand dune vegetation is in various stages of

degradation in different parts. There are innumerable anthropogenic factors

which are responsible for the destruction of dune vegetation: real estate

owners who prepare plots for buildings, hotels or resorts clear all dune

vegetation; roads are laid over levelled dunes thus eliminating the vegetal

cover; beach shacks and various other recreational activities have shown

similar effects as dunes are rendered bare.

7. Litter on beaches: As more people are moving towards the coast, our

beaches are getting dirtier. The Baga - Candolim stretch, Miramar, Colva

and even Benaulim can easily be singled out. For instance, the annual sea

food festival held at Miramar produces heaps of garbage, a part of which

gets mixed with the sand. Large pits in the dunes at Calangute are used to

61

dispose garbage by the public at large. At Colva, the prominent creek is

used as a dumping site for all types of waste. Litter scattered along the coast

ultimately finds its way into the rivers or the sea and is subsequently thrown

back on the beach during the post monsoon period.

8. Salt water ingress: Problems started in recent years when a large number of

bore wells with powerful pumps were installed close to the beach notably by

the builders, the hotel industry and also by private parties. Unchecked

withdrawal of ground water has resulted in lowering the groundwater table

and seepage of saline water into fresh water wells. Salt water ingress into

coastal acquifers is irreversible.

Discussion The relationship between human activities and coastal ecosystems have to

be understood if coasts are to be preserved for the benefit of mankind at large.

The anthropogenic impacts discussed above indicate that construction of resorts

and buildings, dune sand mining and roads on sandy strips are the three major

factors responsible for the degradation of coastal dunes. The consequent result is

the elimination of dunes, the single largest irreversible impact that is being faced

at present. Marine salt water ingress is seasonal.

The destruction of sand dunes in Goa is almost exclusively anthropogenic.

This can be observed in Baga - Candolim where resorts and hotels are dense,

Miramar - Caranzalem, and Betalbatim - Mobor, but more particularly at

Cavelossim. These strips are too frequented subsequent to the promotion of

coastal tourism. Dunes have suffered from the assaults of tourism and other related

activities that have spread over coastal spaces. The existence of sand dunes is

therefore in peril.

Similarly, the desecration of dune vegetation which is crucial as sand

binders appears to be exclusively anthropogenic and is attributed to factors

discussed above. Native plant species are prevented from colonising because of

the preference for the lawn grass and exotic shrubs for landscaping. Real estate

62

developers and owners of resorts have replaced natural vegetation with gravel,

cemented paths, or simply maintained an unvegetated barren surface which is

used for other purposes such as parking. Natural dune vegetation can only be

seen on existing stretches which have so far remained free from development.

Since sand dunes are eolian bedforms which are dynamic and mobile, they

should be allowed and be able to evolve freely and naturally in form and space.

Research has shown that dunes have displaced and migrated naturally by tens of

meters towards the sea as well as away from it as compared to their primitive

location. Since a natural sand dune is in a natural equilibrium with the beach, if the

beach retreats the dune should be able to do likewise (retreat) so as to assure its

role as a sand reservoir in order to maintain the equilibrium between the dune -

beach ecosystem. Since a majority of beaches are in a process of retreating due to

a slow rise in sea levels, the dunes should also retreat landward by rolling on

themselves. For this, ample coastal space is necessary and is to be reserved for

migration, and sand dunes should be at liberty to do so.

The present style of development as observed along the sandy stretches of

Goa, therefore, works against the natural evolution of sand dunes. That was

precisely the reason why our ancestors never occupied sand dunes, but instead,

built houses and roads away from beaches, and always lived behind sand dunes.

This trend can still be observed along the west coast of India. The wisdom of our

ancestors to maintain a perfect coastal equilibrium cannot be questioned.

References Consulted

Alvares, C., 1993. Fish, Curry and Rice: A Citizen’s Report on the State of the Goan Environment, Ecoforum, Goa, pp. 260. Carter, R.W.G., 1988. Coastal environments: an introduction to physical, ecological and cultural systems of coastlines. Academic Press, London, 607 pp. Desai, K., 1995. The structure and functions of the sand dune vegetation along the Goa coast. Thesis, NIO, 218 pp. D’Souza, J.A. et al., 1988. The Regional plan for Goa, 2001 A.D. Town and Country Planning Department, Government of Goa, 108 pp.

63

Frihy, O.E., Fanos, A.M., Khafagy, A.A. and Aesha, K.A.A., 1996. Human impacts on the coastal zone of Hurghada, northern Red Sea, Egypt. Geo-Mar Letts., 16:324-329. Lobo U., 1988. Environmental aspects of silica sand mining from coastal sand dunes. In: Earth Resources for Goa’s Development, pp. 521-523. Mascarenhas, A., 1990. Why sand dunes are needed. Herald, 21 December, p. 4. Mascarenhas, A., 1996. Some observations on the coastal zone management plans of Goa (unpublished report), 25 pp. Mascarenhas, A., 1998. Coastal sand dune ecosystems of Goa: significance, uses and anthropogenic impacts. Submitted to Department of Ocean Development, New Delhi, March 1998, 43 pp. Mascarenhas, A., 1999. Some observations on the state of the coastal environment of Goa, west coast of India. Proceedings, Integrated Coastal and Marine Area Management Plan for Goa, Department of Ocean Development, Chennai, pp. 204-224. Mascarenhas, A., 1999. The Coastal Regulation Zone of Goa: oceanographic, environmental and societal perspectives. Current Science, 77(12):1598- 1605. Mascarenhas, A., 2000. Human interference along the coast of Goa. In: Environmental problems of coastal areas in India, V. K. Sharma (Editor), Bookwell Publishers, New Delhi, pp. 145-171. Mascarenhas, A., 2001. Eolian transport of sand at Miramar: a coastal management issue. Herald Magazine, 29 September 2001, p. 1.

Mascarenhas, A., 2002. The Miramar beach management and development project: a geological viewpoint. Herald, 12 January, 2002, p.1/4.

Miossec, A., 1988. The physical consequences of touristic development on the coastal zone as exemplified by the Atlantic coast of France between Gironde and Finistere. Ocean Shore. Manag., 11:303-318. Nordstrom, K.F., 1994. Developed coasts. In: Coastal evolution: Late Quaternary shoreline dynamics, R.W.G. Carter and C.D. Woodroffe (Eds.), Cambridge University Press, London, pp. 477-510.

64

Nordstrom, K.F. and Mccluskey, J.M., 1985. The effects of houses and sand fences on the eolian sand budget at Fire Island, New York. Jour. Coast Res., 1:39- 46. Paskoff, R., 1989. Les dunes du littoral. La Recherche, 20:888-895. Vogt, G., 1979. Adverse effects of recreation on sand dunes: a problem for coastal zone management. Coastal Zone Manag. Jour., 6:37-68.

65

Ecology of sand dune vegetation

M K Janarthanam Department of Botany, Goa University, Goa – 403206

Sand dunes, with various patterns are found either in the interior deserts or

along the coastal areas. The main difference between coastal dunes and interior

dunes is that the former is subjected to much human interference due to high density

of population along the coastal areas as compared to deserts. The coastal sand

dunes are attracting lot of attention as people have realised their importance in the

coastal ecosystem. The attention is primarily towards conservation of them. The

principal threats to them come mainly from anthrophogenic factors such as sand

mining, tourism, recreational activities, driving, accumulation of trash etc

Dune building process is basically a simple one. The initial ridges are formed

by waves outside the reach of high tides. Occasional storm does it outside the reach

of the normal wave. And further wind blown sand when meet with any obstacle gets

trapped increasing the size of the ridge. These obstacles are usually plants on the

beach. The sand deposition may be on the leeward side of vegetation or lateral long

continuous deposition. These places with primary vegetation are known as

foredunes. Contours of dunes are generally seen along the beaches for long

distance. The plants those help to build dunes play an important role in the

ecosystem. The very existence of the coastal sand dune ecosystem depends on the

vegetation in that area.

The vegetation which forms an essential component in the formation and

stabilization of dunes provides shade, breaks wind velocity, checks evaporation,

helps in organic matter accumulation and increases the water holding capacity. In

essence a chain reaction follows with the formation of the vegetal cover. The

important aspect of the vegetal cover is its ability to break the wind, trap the sand

and prevents the damage caused by the expansion of the sand towards land.

The vegetation of coastal sand dunes and beaches are dealt variously by

different authors. In India, Champion and Seth named them as littoral forests in

66

broad sense. Rao and Sastry (1972) recognised a) open pioneer zone, b) closed

herbaceous zone, c) middle mixed or bushy zone and d) inner woodland zone.

Elsewhere, Turner et al (1962) recognised five zones which correspond to a)

Embryonic dune, b) Fore dune, c) Dune scrub, d) Shrub woodland and e) The dune

woodland. Each zone is represented or dominated by particular floristic composition.

The pioneer plants are hardy, can tolerate salt spray, strong wind and sand

blasts. They also withstand the occasional washing by sea water during high tides.

They have special morphological and anatomical adaptations and show some

unique reproductive behaviour.

The ecology of sand dune vegetation is subject of attention and various

aspects of comparative ecology are not fully understood. The broader level

ecological understanding include a) the correlation between plant species and

distance to the sea, b) general floristic composition, c) vegetation change over time

and space, d) effect of denudation on sand dunes, e) reproductive biology including

pollination and pollinators and seed dispersers, f) the role of mycorrhiza in the

extreme environments, g) interaction with animals (eg. Nesting sites), h) quantitative

ecology, i) impact of exotics on native plants, etc. The socioeconomic aspect of

ecology forms an important deciding factor in their conservation. Though some of

these aspects are covered as case studies, most of the questions remain largely

unanswered.

Having realised the importance of vegetation in coastal ecosystem,

conservation of vegetation as the primary way of conserving and stabilizing sand

dunes is being worked out. The various means of conserving sand dunes include a)

not disturbing the vegetation, b) avoiding trampling, cycling, motoring and playing on

sand dunes, c) fencing of dunes and giving access to beaches only through

designated paths, d) enforcing coastal zone regulations strictly, e) plantation towards

land side etc.

67

PHYTOPLANKTON AND CAPACITY BUILDING

K.G. HIREMATH Head of the department of Botany Dhempe college of Arts & science

Miramar, Panaji, Goa 403001

Management of natural resources on a sound ecological basis confronts us with

problems that are biological. We are dealing with processes which determine the

lives of organisms and which are themselves subject to action of living things. So, it

is inevitable that biological methods provide advantageous possibilities for

Environment Impact Assessment. It is therefore imperative that the studies on

phytoplankton has to be a part of CAPACITY BUILDING

Capacity building

Capacity building means empowering the community through education, training and organizational development. Empowerment involves strengthening the communities’ access and control over coastal resources and in equity. Equity means that equal access to opportunities among people and among classes. Capacity building helps to build a common understanding of often complex and interrelated aspects of coastal resources. By emphasizing local issues, environmental education can build awareness and skills that contribute to the capacity of individuals. Indigenous knowledge has to be tapped: information, beliefs, tendencies, practices, tools and skills have to be used. People should have incentives and reasons to expect that investments in conservation will bring future benefits, they do protect environment. Coastal zone

Coastal Zone is that space in which terrestrial environment influences marine environment and vice-versa. Coastal zone may also be defined ‘ecologically’ as the land area influenced by sea. It may be defined ‘politically ’by some arbitrary distance inland from high tide level and also may be defined ‘socially ’as the area occupied by people dependant on the sea for livelihood. Coastal zones have multiple source of income and therefore world’s largest metros are found on the coasts. Although they are highly productive, they are often under serious threat due to human activities which have forced changes in ecological structure, productivity, and diversity. The monitoring of theoretical and experimental aspects will help to assess and possibly predict the state of coastal ecosystem. Coastal zones are more productive than open sea due to occurrence of multiple plant subsystems. Specifically benthic

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macrophytes and phytoplankton .Phytoplankton make use of turbulence in coastal zone to assist production. Estuary

Physical, chemical, and biological characteristics of estuaries provide a favourable setting for diverse flora and fauna and are among most productive of earth’s aquatic ecosystems. Estuaries incorporate terrestrial, marine, and lake dynamics. They often act as ‘sinks’ for nutrients and pollutants and are considered as ‘marine lungs’. They are highly productive due to relatively complete and rapid heterotrophic recycling. Information about phytoplankton is a valuable contribution to the assessment of marine pollution in general and coastal zone in particular. Phytoplankton Organisms which are unable to maintain their distribution against the movement of water masses are referred as ‘plankton ‘. Planktonic plants are referred to as phytoplankton. Phytoplankton is composed of single cells or of relatively simple organized, small colonies, and comprise a considerable diversity of algal groups. Around 4000 species of phytoplankton have been identified all over world. Major Groups of phytoplankton

Group Region

Cyanophyceae Coastal Cryptophyceae Coastal Chrysophyceae Coastal Bacillariophyceae All Coccolithophorids Oceanic Euglenophyceae Coastal Prasinophyceae All Chlorophyceae Coastal Pyrenophyceae All

Diatoms and Dinofagellates are the common net-phytoplankton, however some cyanophyceaen members are known to form blooms. Diatoms are large, widely distributed and well preserved and provide time scale context. Phytoplankton can be classified: On the basis of their relative size as follows 1 Ultra-plankton -< 2µ 2 Nanno-plankton -2-10µ 3 Micro-plankton -10-2000µ 4 Mega-plankton - > 2000µ

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On the basis of region of occurrence as;

1 Oceanic - occurring in open ocean 2 Neritic - occurring in coastal water

Estimation There are many ways to understand and estimate the phytoplankton dynamics. Each method has its own merits and demerits

Method Merit Demerit

COUNTING:A known

amount of water is passed

through a nybolt cloth with

known pore size (10µ or

20µ).Sub-samples are

then transferred to Sedge-

Wick Rafter for counting

Gives an idea of density,

diversity and floristic

composition of phytoplankton

Dead organisms are also

counted, Smaller organisms

which have greater metabolic

rate can not be counted,

Identification requires an

expert,

It is laborious and time

consuming,

BIOMASS: It is estimated

by estimating chlorophyll-a

content of a known amount

of water sample.

It gives an estimation of the

standing stock of living cells

only. It is very fast and easy

to estimate.

Standing stock does not give a

time scale profile.

No information about diversity

will be available

PRIMARY

PRODUCTVITY: This

refers to the amount of

Carbon fixed by

phytoplankton in a

specified time .It is

estimated by oxygen

method or by using

radioactive carbon.

It gives an exact estimation of

primary productivity of

phytoplankton. It takes into

account of the contribution by

all sizes of phytoplankton

This method lacks information

about the floristic composition,

density and diversity

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Species composition Phytoplankton assemblages differ with respect, to latitude, temperature, nutrient

levels, light, seasons and other environmental factors. Diatoms usually dominate the

net plankton followed by dinoflagellates and blooms of some opportunistic species.

Opportunistic species increase in number to take advantage of certain changed

environmental factors and appear less frequently. They respond to existing

conditions favourable to their development. They may not be consistent on annual

basis. They may become sub-dominant one year and passive at other times. Nano-

planktons are dominated by coccolithophorids and other nanoplanktons.

Nanoplanktons are very important because they contribute between 50-90% of the

biomass. They also have higher rate of metabolism. On the basis of species

composition phyto-hydrological classification can be undertaken. Suitable

composition and density is required for zooplankton growth, which are food for

fishes.

SUCCESSION Ecological succession is a process of self-organization, based on interaction among

species and between organisms as well as environment, which is manifest in many

measurable changes in the ecosystem. Succession is the result of simultaneous

interaction of a number of factors rather than the effect of one parameter and it may

be obvious in areas subject to monsoons and upwelling. Succession is a feature of

common occurrence in temperate waters, however succession is observed in

tropical waters also. Phytoplankton studies over several years have shown that

several dominant species remained as seasonal dominants over years and several

other species also become dominant. A few dominants play major role, yet allowed a

broader base of other species to develop at higher concentrations, often producing

significant out bursts.

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Species Diversity Species diversity, defined in many ways is simply the number of species found in a

unit area or it can be referred to the heterogeneity (or lack of it) in a community. It

depends upon the number of species present and distribution of individuals among

species. Diversity is greater when the species are more evenly distributed. Diversity

is thus considered as an index of maturity of an ecosystem, mature ones producing

less entropy (measure of disorder) than immature. Diversity expresses both time and

effects of

environmental rigor and instability on the rates at which species are added or

removed from the communities. There are three stages in changing diversity of a

community:

1. Turbulent waters with few species surviving; occasional blooms; low

diversity.

2. Inflowing water, bringing more species; passively increasing diversity.

3. Highly stratified water with a mature community; low crop with high diversity.

Species diversity can be quantified using several indices; most commonly used is

Shannon-Weiner Index. Species evenness is another index which is a component

of diversity. It gives an idea about of the equitability (evenness) of the species

distribution in area. Usually high equitability indicates high diversity. Reduction in

equitability usually occurs with an increase in oligomixity (predominance by some

species). High equitability and diversity indicate healthy condition.

1Turbulent waters with few species surviving; occasional blooms; low

2 Inflowing water, bringing more species; passively increasing diversity.

Blooms

Phytoplankton blooms account for one of major carbon fluxes in ocean and is an

interesting biological event taking place in the sea. A phytoplankton bloom implies

an abnormally high cell concentration due to combination of cell division and cell

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aggregation. “Red Tide” is a common name for such a phenomenon where

phytoplankton species contain reddish pigments and bloom such that the water

appears to be red. All blooms need not be red in colour. The onset, development

and magnitude of blooms represent a complex process involving changes in size,

biochemical composition and metabolic rates and are frequently terminated by

nutrient depletion. Nutrient exhaustion leads to decay of blooms which cause oxygen

depletion, leading to death of fishes. Some blooms are consistent whereas some are

opportunistic species. Harmful algal blooms (HAB) are known to contain toxins. They

have caused severe habitat degradation, economic loss and untold human miseries.

An international plan on Global Ecology and Oceanography of HAB (GEOHAB) has

been developed to coordinate the research and cooperation amongst the nations

facing HAB problems. The health problems posed to humans are referred as the

“Poisoning Syndromes” Following are various health problems associated with

humans:

1. Amnesic Shellfish poisonings (ASF): gastrointestinal and neurological

disorders.

2. Paralytic Shellfish poisonings (PSP): purely neurological, onset is rapid.

3. Ciguatera Fish poisonings (CFP): gastrointestinal and neurological

disorders and cardiovascular symptoms.

4. Neurotoxin Shellfish poisoning (NSP): identical to CFP

5. Diarrheic Shellfish poisoning (DSP) : diarrhea, nausea, vomiting, abdominal

cramps

6. Cynotoxin poisoning (CP): block signal transmission from neuron to muscles.

Diel Changes

Diel or circadian (Diurnal) rhythms are quite apparent in photosynthetic organisms

because they require light .Every parameter in planktonology is subjected to some

circadian periodicity, even when observations are lacking or conflicting. In tropical

waters net-plankton assimilation ratios were highest in the afternoon both in

eutrophic and oligotrophic waters while nannoplankton exhibited maximum ratio

during morning in oligotrophic and afternoon in eutrophic waters.

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Nannoplankton

Nannoplankton contributes significantly to the productivity and biomass of various

marine provinces. An important feature of nannoplanktons is that their optimal rate of

multiplication is generally higher than net-phytopankton, following the broad

generalization that the rate of uptake, growth and division is higher with reduced cell

size. Various studies allover the world have shown that nannoplankton contribute

anywhere between 50-60% of biomass.

Wind Oceanographic studies conducted during last few decades in the coastal regions of

the world have identified the stress exerted by winds ocean surface as one of the

main forcing functions influencing coastal processes. Physical processes dominate

over biological and chemical processes in controlling phytoplankton variability for

certain wind velocities and have marked influence on spatial structure of

phytoplankton. Local biological processes (growth and grazing) can dominate the

distribution (and create large lateral gradient) during the periods of weak water

circulation, but an advective transport can dominate during episodes of enhanced

circulation.

CONCLUSION

CAPACITY BUILDING

• It is a long term process and the necessary activities vary from single course to the installation of a complete environmental monitoring system

• It requires involvement of government, international organizations, the private sector, donors and NGO’s.

• All participants must recognize the need to sustain capacity once it has been built.

• Creating awareness in the minds of public and policy makers to entice the national and international support.

• It should include provisions of skills, experience and infrastructure.

74

PHYTOPLANKTON It is impossible to evolve a general pattern of phytoplankton productivity which would be a representative of all tropical and sub tropical waters. It is all the more difficult for coastal regions because they are influenced by local climate, run off, local upwelling, and other factors. However the knowledge of phytoplankton can be an important tool for understanding the coastal processes. Happy is he who lives to understand Not human nature only, but explores All nature- to the end that he may find The law that governs each; and where begins The union, the partition where that makes Kind and degree……… WORDSWORH “The Excursion”

75

Coastal Pollution – Status and Measures for Prevention

X N Verlecar,

National Institute of Oceanography, Dona Paula-Goa 403 004

India has long coastline of 7,516 km. Out of its 1 billion population, nearly 20% live

in the coastal areas. Many highly populated and industrialised cities like Bombay,

Madras, Calcutta, Cochin, Visakhapatnam are located along the coastal areas.

There are 11 major ports and a number of minor ports handling shipping to various

degrees of intensity. The coastline of the mainland belongs to nine States and two

Union Territories. The coastline of the islands of Andaman, Nicobar and

Lakshadweep (Laccadives) group of islands constitute nearly 2,000 km. While land

area of this country is around 3.3 million km2, it has equally large Exclusive

Economic Zone of 2.02 million km2

Ecosystem is diverse consisting of rivers, estuaries, wetland, etc. Enormous use of

the water resources by township and industries has resulted serious pollution

problems. The prevailing ecosystems and problems associated with the same are

discussed below

1. COASTAL ECO-SYSTEMS 1.1 Coastal wetlands

These comprise of brackishwater areas including marshes, backwaters,

mangroves, inter- and sub-tidal regions, which measure around 14,16,300 hectares.

These areas act as feeding and nursery grounds for a variety of commercially

important fish, prawn and crabs, media for inland transportation, fishing etc.

1.2 Mangroves

Mangroves are located along the islands, major deltas, estuaries and

backwaters of the east coast of India. They also exist along the oceanic island

groups of the Andaman and Nicobar. The total mangrove area is estimated to be

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6,81,976 hectares. While the mangroves along the west coast of India are dense,

scattered and comparatively small in area along the West coast. Gangetic

Sunderbans (418,888 ha), Andaman-Nicobar Islands (115,000 ha), Krishna, Kaveri

and Godavari deltas and Mahanadi delta are some of the best mangrove formations

of India.

Mangrove forests mainly function as spawning, breeding and nursery grounds

for nearshore estuarine organisms like fishes, crabs, prawns, molluscs, etc. Some of

the common and economically important species are Mugil cephalus, Hilsa ilisha,

Lates calcarifer, Scylla serata, Meretrix casta, Crassostrea grephoides, and

Penaeus spp.

Apart from the captive and culture fisheries, mangroves are also important as

"coastal stabilizers" and "shelter belt areas". These formations protect the coasts

and the landward areas from erosion and cyclonic destructions to some extent. The

Mangrove forests of India are also important from a wildlife, recreation and

education point of view. "Project Tiger" of Sunderbans and "Crocodile Sanctuary" in

the Mahanadi delta are examples of such activities.

1.3 Coral reefs

Palk Bay, Gulf of Mannar, Gulf of Kutch, Central West coast of India,

Lakshadweep atolls, and Andaman-Nicobar Islands are some of the coral reef

formations along Indian coast. Both the coral atoll and the fringing coral reefs are of

utmost significance in Indian waters. A few species of corals have recently been

reported from the Malvan (Maharashtra) coast. Some 32 genera from Minicoy

Islands, 34 genera from Palk Bay and Gulf of Mannar, 25 genera from Andaman

Islands, 9 genera from Lakshadweep and 3 genera from Nicobar Islands have also

been reported. A total of 342 species belonging to 76 genera from the seas around

India have been described.

Primary productivity studies of coral reefs in Indian waters indicated

comparable rates with other reefs and marine ecosystems. Often the large benthic

77

algal communities and extensive seagrass beds are equally important as the energy

released from them is transferred to higher trophic levels by way of the detrital food

chain.

1.4 Marine national parks and marine sanctuaries:

On account of their high bio-diversity, the Gulf of Mannar and Wandoor

(Andaman) have been declared as Marine National Parks and Malvan coast

(Maharashtra), Gulf of Kutch, Jamnagar as Marine Sanctuaries. There are a number

of other specialised ecosystems which exhibit a large variety of marine life and they

include Chilka and Pulicat Lakes, Point Calimere, etc.

2. ACTIVITIES IN MARINE AREAS AND ENVIRONMENTAL PROBLEMS

2.1 Land-based activities causing pollution

2.1.a Disposal of domestic sewage

Demographic pressure in the urban cities and towns has resulted in the

production of enormous amounts of domestic waste materials. These materials

reach the marine environment either directly or indirectly through rivers, creeks,

bays, etc. The domestic sewage contributes to the largest amount of waste and it

has been estimated that approximately 18,240 million liters per day (MLD) (as of

1994) reach the coastal environment of the country. These wastes predominantly

contain degradable organic matter which utilises enormous amount of oxygen from

seawater for its oxidation. The low oxygenated seawater leads to decrease of

population of flora and fauna.

Domestic wastes are discharged mostly in untreated condition due to the lack

of treatment facilities in most of the cities and towns. It has been reported that only

primary treatment facilities are available in cities and towns where the population is

more than 100,000 and the capacity of the plants is not adequate for the treatment

78

of the total waste generated in the city. For example, in Bombay, the treatment

facilities are available only for 390 MLD as against 1,200 MLD of domestic sewage

which is generated. Due to such partial treatment, the chemical characteristics of the

wastewater retain almost their original features and cause damage to the

environmental water quality.

2.1.b Discharge of Industrial Waste

India is one of largest industrialised nations in the world. Major industrial

cities and towns of the country such as Surat, Bombay, Cochin, Madras,

Visakhapatnam and Calcutta are situated on or near the coastline. The total quantity

of wastes discharged by these industries is estimated to be 0.67 x 109 m3 (as of

1994). While the major industries discharge treated effluents into the sea, numerous

small and medium scale industries discharge the untreated effluents into the

adjoining wastewater canals, municipal drains, creeks, etc.

2.1.c Non-point sources of pollution

Agriculture being the main occupation, large quantities of fertilizers and

pesticides are used to sustain the agricultural production. This is essential in order

to meet the food requirements of its population. The run-off from the agricultural

fields reaches the rivers and ultimately to the seas. The major rivers in Deccan area

are rain fed and non-perenial. As a result they shrink into rivulets when hot season

opens. During this dry period, when the water is less, the chemical elements

present in the run-off undergo biogeochemical changes in the riverine environment

itself with minimum input into the sea.

2.2 Status of marine pollution in India

79

A nation-wide marine pollution monitoring programme operating for the last

10 years has identified areas of clean sea, low levels of pollution and areas of

concern. It has been found that the sea beyond 2 km all along the coast except in

Bombay is clean. In case of Bombay, the sea beyond 5 km is clean. The inland

port/creek waters of Veraval (Gujarat) and Bombay were identified as areas of

concern.

2.3 Other activities responsible to create pollution problems:

Ship-breaking industries

At present, the activities related to the breaking of ships have been reported

from the coasts of Gujarat, Maharashtra and, to a certain extent, off Tamil Nadu.

During the ship-breaking activities, the major components like engine, etc., are

removed and offloaded to the shore. The hull and other steel parts are cut into

different sizes and transported as scrap. During the operation, the iron particles and

the paint containing lead, get into the marine environment while the soluble matter

contaminates the surrounding environment. The iron particles settle in the sediment.

Increased concentrations of lead in sea water is lethal to organisms and the iron

debris settling in the sediment causes damage to the benthic organisms particularly

the filter feeders like clams, mussels, etc.

2.4 Sea-based activities causing environmental disturbances and pollution

Oil pollution is one of the major sources of pollution from the sea-based

activities. India imports nearly 30 metric tons of petroleum products every year

through its major ports located at Kandla, Bombay, Cochin, Madras and Calcutta.

India also produces oil through its inshore and offshore oil fields. The details of

tanker terminals, oil depots, refineries as well as offshore oil fields in India are given

below:

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Port/Area Function

Gulf of Kutch Ship to ship transfer

Port Kandla Single point Mooring Buoy

Vadinar Single point Mooring Buoy

Bombay High Offshore oil field

Bombay (Offshore) Ship to ship transfer

Bassein Offshore oil field

Ratna/Heera Offshore oil field

Butcher Island Marine Terminal

Bombay Refinery/Depot

Marmagoa Marine Terminal

Mangalore Marine Terminal

Cochin Marine Terminal

Tuticorin Marine Terminal

Cauveri Offshore oil field

Madras (Offshore) Ship to ship transfer

Madras Marine Terminal

Vishakhapatnam Marine Terminal

Vishakhapatnam Offshore oil berth ìVIZAGî

Krishna Offshore oil field

Godavari Offshore oil field

Mahanadi Offshore oil field

Haldia Marine Terminal

Refinery / Depot

Calcutta Marine Terminal

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2.5 Oil production in offshore platforms and handling in Ports

The total quantity of oil produced from the offshore wells of ONGC along the

Western coast of India is approximately 30 million tons per day. This oil is

transported mainly through the pipelines and the oil tankers. Additionally,

approximately 30 million tons of crude oil imported from foreign countries is being

handled at major ports and the total quantity of petroleum products handled in major

ports is about 50 million tons per year at present and is likely to increase in future.

This crude oil is carried by tankers and ships which number more than 1,600 per

year. The Shipping Corporation of India (SCI) also operates more than 24 crude

carriers which carry imported oil to the major ports of the country.

The western part of the Indian Exclusive Economic Zone, i.e. Arabian Sea

adjoining peninsular India, forms the main international tanker route for oil tankers

originating from the Persian Gulf. It has been estimated that some 330 million tons of

crude oil is transported annually along this route, involving approximately 2,500

laden tankers. The preferred route is through the 9o channel between the Maldives

and Lakshadweep Islands, during the Southwest monsoon (May to September), and

north of Lakshadweep following the 200-m depth curve west of Mangalore, at other

times. Considering the large volume of oil transported and high rate of tanker

movement the probability of tanker accident is high - once every few years. The last

major accident in the area occurred in January 1993 when two tons of oil spilled in

the Nicobar Sea.

2.6 Radioactive and thermal wastes

Although power generation is mostly thermal in India, nuclear power is also

being generated. So far no serious harm has been reported from these sources, but

fly ash from thermal power plants invariably creates environmental problems.

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Radioactive wastes from nuclear power plants are normally disposed of

according to strict international conventions. However, their heat generation poses

several problems. Nuclear power plants normally release 50% of their generated

heat to the coastal marine environment. Localised damage to ambient flora and

fauna appears to be unavoidable.

3. Monitoring of coastal areas:

Increasing incidence of aquatic pollution has resulted in considerable damage

to the marine and estuarine biota. In order to keep the pollution impacts within the

permissible levels, Government of India, in 1991, issued a major notification under

the Environment Protection Act, 1986, framing rules for regulations of various

coastal zone activities. Along with this programmes on monitoring of the coastal

areas have been initiated by various research Institutes.

The Notification on Coastal Regulation Zone 1991 (as amended from time to

time) lists certain prohibited and regulated activities related to integrated coastal

zone management and sustainable development. Its provisions also prohibit and

regulate developmental activities in the Coastal Regulation Zone. The

effluents/discharges from various resources have to meet the standards listed in the

EP (Act) 1986 before being discharged in the marine waters.

The management of resources in high seas is with Department of Ocean

Development, while management of resources in the Coastal Water lies with

Ministry of Environment and Forests.

With regard to the management of Marine Environment and Biodiversity as

well as for their monitoring, major activities relate to the monitoring of the health of

India's coastal waters and to capacity building and infrastructure development to

facilitate adoption of the concept of Integrated Coastal and Marine Area

Management (ICMAM).

83

The Coastal Ocean Monitoring and Prediction Systems (COMAPS) is a

programme being carried by the Department of Ocean Development since 1990-91

with the objective of constantly assessing the health of Indian seas on a long-term

basis. The status of marine pollution in the coastal waters has been assessed and

current level of pollution in the waters has also been determined.

In 1998, the Department took up an infrastructure development and capacity

building programme to facilitate adoption of the concept of Integrated Coastal and

Marine Area Management (ICMAM) by coastal areas in the coming years in which

National Institute of Oceanography played a major role. The programme focuses on

development of expertise in ICMAM oriented activities and dissemination of

knowledge gained to the coastal areas through organized training programmes.

Towards accomplishing these activities, the following priority activities are being

undertaken: Capacity Building and Infrastructure.

4. Legislation:

To address the preservation and sustainable use of fragile ecosystems,

State/Union Territory level Waste Zone Management Authorities have been set up,

and these will prepare an Integrated Coastal Zone Management Plan for ecologically

important zones.

To address integrated coastal zone management and sustainable

development, the following legislation has been adopted:

• Environment Protection Act (EPA), 1986, under which Coastal Regulation

Zone 1991 has been notified.

• Forest Conservation Act, 1980.

• Standards for discharging effluents are listed in the Environmental Protection

Act 1986.

In addition, the following Guidelines have been adopted:

84

• Guidelines under Environment Impact Assessment (EIA) notification for

setting and operating various projects.

• Guidelines on Sustainable Aquaculture Development for regulating coastal

aquaculture.

Major Groups are involved through public hearings that have been made mandatory

before any project listed in EIA notification is cleared.

5 Oil Spills and Shipping:

The western part of the Indian Exclusive Economic Zone, i.e., the Arabian

Sea adjoining the peninsular India, forms the main international route for oil tankers

originating from the Gulf. It has been estimated that some 450 mt. of crude oil is

transported annually along this route, involving approximately 2500 laden tankers.

Considering the large volume of oil transported and increased ocean traffic, the

probability of tanker accidents is high. The last major accident in the area occurred

in January 1993 when a few thousand tonnes of oil spilled into the Andaman Sea.

Any accidental spillage of oil along the tanker route will cause severe and in some

cases irreparable damage to the marine ecosystem.

In addition to offshore oil exploration and production activities, transfer

operations of oil at single buoy mooring stations, as well as lightening and bunkering

operations in major ports, cause spillage of oil.

6 Disposal of Domestic and Industrial Waste:

It has been estimated that a large quantum of domestic sewage reaches the

coastal environment each day. These wastes contain degradable organic matter,

which utilizes enormous amounts of oxygen from seawater for its oxidation. The

resultant fall in oxygen in seawater leads to a decrease in the population of marine

85

flora and fauna. Domestic wastes in certain coastal areas are discharged without

treatment due to lack of such facilities in most cities and towns.

7 Capacity building, education, training, etc:

Surveys for collection of the baseline data on almost all potential pollutants in

the marine environment are under progress. The data collected on various

pollutants in the seas around India indicates localized problems both short-term and

long-term. Several hot spots have been identified so that priority can be given to

these areas where water quality is deteriorating seriously and the wastes that are

being disposed of near ecologically sensitive zones

The transportation of oil through Indian Ocean can cause serious problems

particularly because of oil tanker disasters and offshore activities. The worst

affected ecosystems due to this problem are the coral reefs and sandy beaches.

Clean-up activities are the most important solution to prevent damage from oil

spill to coastal ecosystems – Plan should be ready especially for strategic areas

which have a high risk of being affected by oil spill.

Reasearch in the field of oil pollution have been in progress in India for a long

time. A substantial amount of data have been collected on the toxicity of several

chemical dispersants and their suitability to Indian marine conditions. Since oil will

continue to be needed in the next few decades and will have to be transported by

sea, oil will keep contaminating the environment. Therefore, we need better

methods of oil removal, we need a scientifically and technologically advanced

approach to acquire much of the information needed to guide decision-making for

managing the coastal regions.

8 Priorities for future action

A systematic long-term study of pollutants in the Indian Ocean and their

effects on biota is needed. Except for some contaminants which could be precisely

86

measured for a long time little is known about the levels and distribution of the

critical pollutants in water, sediment and biota. We need more information on the

current sources of pollution,the routes of distribution in the environment and their

progress through ecosystems. Studies concerned with bioconcentration,

bioaccumulation and biomagnification of pollutants should be encouraged.

Research on the toxic effects of critical pollutants on the marine environment

and its living resources needs to be greatly expanded.

Priority should be given to biomonitoring, as living organisms can serve as

excellent quantitative as well as qualitative indices of pollution.

87

Seaweeds: promising plant of the millennium.

V K Dhargalkar & Neelam Pereira.

National Institute of Oceanography, Dona Paula, Goa.

Introduction: Seaweeds , a group of marine macrophytes, also known as marine benthic

algae are one of the most important living resources of the world ocean. On the

basis of coloration and morphology, seaweeds are grouped as Chlorophyta,

Rhodophyta and Phaeophyta. Its occurrence varies with seasons and the tidal

levels. Generally, found in the intertidal zones , they are alternately exposed and

submerged by the tides. They are also found in the subtidal area up to a depth,

where 0.1% photosynthetic light is available.

Seaweeds are considered economically significant due to their output of

various industrial products like agar, alginate and carrageenan. The recent utilization

of seaweeds can be divided roughly into industrial use of phycocolloids in

developing countries and as food supplements in far East.

International Status: The total seaweed production of the world in the year 2000 was 7.9 million

metric tones. Out of which, 6.8 million metric tones come from cultivated area of 200

x 10 3 hectors (FAO, 2000) (Table 1).

Alginate, carrageenan and agar are extracted annually from about 9,00, 000

tons (wet weight) of harvested seaweeds world over. This represents about 25% of

the global seaweed harvest. In 1990 average alginate production was 22,000-25,000

tons. Carrageenan has annual sales of over US $200 million. The market for

carrageenan has grown by at least 5% per year for the last 25 years. The Philippines

is the world's leading supplier of Eucheuma accounting for approximately 70% of the

world supply. The world market value of agar has been assessed at US $200 million.

88

Japan, Spain, Chile, China, Mexico and the Republic of Korea are the main

countries producing agar.

National Status: The potential harvest from Indian ocean is about 8,70,000 tones (wet weight),

out of this, 2,20,000 tones of red algae and 6,50,000 tones of brown algae are

harvested from the Indian ocean. The information available on sub tidal marine

algae along Indian ocean is scanty compared to that of intertidal region. Thus it also

becomes necessary to explore the sub tidal regions. Of the total seaweed

production, Indian ocean contributes 27% (20% brown and 7% red).

The Indian coastline altogether showed presence of 844 species (including

blue green algae) with maximum Rhodohyta (320), followed by Chlorophyta (165)

and Phaeophyta (150). Out of these maximum number have been recorded from

Tamil Nadu (302) followed by 202 species of Gujarat, 159 in Maharashtra, 82 in

Goa, and 89 in Lakshwadeep group of islands. Maximum biomass was harvested

from Gulf of Kacchh (Gujarat) followed by Tamil Nadu coast (Deshmukhe et al.,

2001).

Historical Use of Seaweeds : Macroalgae harvested from naturally occurring wild populations have been a

commercially valuable resource for food, fodder and chemicals for centuries. One of

the earliest records, “The Chinese book of Poetry” indicates that sea vegetables

were a delicacy way back during the times of Confucius. “Bellum africanum”, written

in 46 B.C. states, “the Greeks collected seaweeds from the shore and fed their

cattle”. Throughout Europe and Great Britain, seaweeds have been used for many

years to replenish the soil and promote plant growth. Irish, mixed seaweeds into

their meager soils to augment its nutrient and humic value. During World War I and

II, the US made extensive use of seaweeds to provide critical wartime materials.

Even, the Indian traditional science, Ayurveda has mentioned the goodness

of algae for human health. Algae, both marine and fresh water are known as

“saivale” in ayurveda and have many times been referred to as possessing

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medicinal properties. They were used for cooling the body as well as regulating the

body temperature and bringing down the fever. (Misra and Sinha,1979).

Food: Seaweeds have been a staple diet in Japan and China for a very long time. It

has been extensively used in a number of food products. Among the green algae,

the sea lettuce or green laver (Ulva lactuca) used to be eaten as salad, chiefly in

Scotland. Among the Phaeophytes, fishermen of Edinburg ate young stipes of

Laminaria saccharina. It was eaten along with Chondrus crispus to prepare a

composite jelly called as ‘Pain des algues’ or seaweed bread. Dried, ground and

desalted algae were used to make bread in Norway. The Japanese made maximum

use of seaweeds in diet. Kombu is considered as most important item of seaweed

food, made from laminariales species. A very delectable product, sold in North West

America, called as ‘seatron’ is prepared by desalting, flavoring and candying

portions of stipes as well as blades of giant Nereocystis (Greville, 1830; Smith,

1905).

Seaweeds find a large range of applications in food industry as stabilizer,

emulsifier, thickener etc. It’s used in making ice creams, soups, and jellies, breakfast

cereals, beverage industry, confectionery, bakery etc (Greville 1830 and

Smith,1905). EMC (Epoxy Methyl cellulose), a derivative of seaweeds, is used as a

decrystalizer in making ice creams.

Animal Feed: Today in a number of countries, animals still regularly feed in certain regions

upon fresh or cooked seaweed. In Iceland, fresh seaweeds are commonly employed

as a food for sheep, cattle and horses. Laminaria saccharina, Rhodymenia palmata

and Alaria esculenta are used for feeding cattle. In Scotland, Pelvetia canaliculata

are preferred by cows hence called “cow-tang”. While, fruiting plants of Ascophyllum

are preferred by pigs and are called as “paddy-tang” (Chapman, 1970). Fresh

seaweed has been used for animal feeds on the American coast where it is said to

have increased health and fertility of both cattle and poultry. The only reference to

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seaweed and for animal feed in tropics comes from Hong Kong where species of

Sargassum are dried and used as pig feed (Kirby 1953). It has been established that

seaweed meal increases fertility and birth rate of animals and also improves yolk

colour in eggs (Chapman and Chapman, 1980). Chemicals: Starches, potash, iodine are some of the chemicals present in the seaweeds.

French used to burn seaweeds as source of potash to get salt and soda. Kelp soda

served in manufacture of glass (Chapman and Chapman, 1980). Algae primarily

used in Europe were species of Laminaria, Fucus and Ascophyllum nodosum.

Seaweed was most important raw material for extraction of iodine and is still an

important source for extraction of iodine in Japan and USSR (Hoppe,1960).

Vitamins, amino acids, carbohydrates, sugar alcohols, enzymes, fats, lipids are

some of the other products found in seaweeds (Chapman and Chapman, 1980).

Industrial Products: The phycocolloids viz ; agar, carrageenan and alginates are extracted from

Rhodophyta and Phaeophyta group of seaweeds respectively. The total harvest

from Indian coast is about 100,000 metric tones (wet weight) (Table 2).

Agaraophytes like Gelidiella aecerosa and Gracillaria edulis and alginophytes like

Sargassum and Turbinaria are employed by the Indian seaweed industry. There are

about 24 small scale agar producing industries and 14 Sodium alginate producing

industries. With a turnover of 60-90 tones of agar and about 500 tones sodium

alginate (Oza and Zaidi, 2001).

Hoppe and Schmid(1969) has given a broad classification of these industrial

products based on their utilization (Table 3).

Alginates: it is a term used for a salt of alginic acid. It is used in pharmacy as emulsifier,

suspension agent or stabilizer. These serve as film forming, as jelling or protective

colloids. They are used as fillers in manufacture of tablets, pills, lozenges etc.

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Sodium alginate is used in slimming agents. Calcium alginate is used in

production of capsules. Alginate serve as thickening and dispensing agents in

ointments, creams, jellies, liquid emulsions, lotions, toothpaste, hair cosmetics, hair

dyes. The ability of alginic acid to form insoluble complexes with strontium helps in

elimination of heavy metal toxicity in humans.

Agar: It is a dried, amorphous, gelatinous extract of agarophytes. It is utilized for

its jelling strength, in food industry. It is used in preparation of cheese, as a stabilizer

of mayonnaise and salad dressings. It is also used as clarifying agent for beer,

wines and

liquor. In pharmacy it is used as a laxative for chronic constipation. It is also used as

substratum for bacterial culture. In cosmetic industry it serves as stabilizer for

emulsions.

Carrageenan: it is a salt of carageenic acid and is extracted from Chondrus crispus and

Gigartina stellata. Carageenan is used in production of soft and processesed

cheese, syrup products, whipped cream products, ice cream, and water gels for

deserts. Besides, it is also used as an emulsifier in pharmaceutical industries for

example in cod liver oil emulsions and binding agents in tablets, cough droplets etc.

In cosmetic industry they are used as thickening agent in manufacture of skin

ointments, creams, lotions etc. They are also used in textile, leather and paper

industries as stabilizers and thickening agents.

Manure / Fertilizer: In the 12th century, seaweeds were used as manure on coastal lands of

France and also in Ireland, Scotland and Norway. It is mainly the large brown algae;

certain red seaweeds that produce lime (CaCo3) are also used. In China, spp. of

Sargassum are used fresh, dried or burnt form and are applied to the soil. This

manure is generally used for growing peanuts and sweet potatoes. In Brazil, Ulva

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and Enteromorpha as well as Hypnea are used as manure for coconut trees

(Schmid & Hoppe, 1962). Recently adopted technique, of spraying fertilizer on the

plants has increased nutrient absorption efficiency in the plants. Leaves absorb

nutrients with in 10 to 15 minutes of its application. Many brands of seaweed liquid

fertilizers like Maxicrop (UK), Kelpak 66 (South Africa), Seagrow (New Zealand),

Algifert (Norway), Plantozyme, Shaktizyme (India) etc. are available in the market.

The diluted extract when sprayed on plants, show beneficial results in terms of

health of plants, increase in rate of growth, resistance to pests, higher yield of 25 to

30 % etc (Dhragalkar and Untawale,1980) Medicines: Seaweeds have many other important but low volume uses. A number of

them have been used for drugs, including anti coagulants, antibiotics, anti-

helminthes, anti-hypertensive agents, and reducers of blood cholesterol, dilatory

agents and insecticides.

Seaweeds are best natural food source of bimolecular dietary iodine. Some

seaweeds contain 1000 times as much iodine as cod, an average iodine containing

fish. Seaweed provides di-iodotyrosin (DIT) which is precursor to forming the

essential thyroid hormones, Thyrosin (T4) and Tri-iodothyronine (T3) which increase

oxygen consumption, influence growth and development, energy metabolism and

protein synthesis (Davis,1991).

It has been suggested, amongst other things that, seaweeds have curative

powers for Tuberculosis, Arthritis, Colds and Influenza, Worm infestations etc.

Rhodophyceran alga, Digenia simplex is made into a drug, in South China, as an

anti-helminthes. Ascophyllum nodosum is known to have anti-bacterial effects. Irish

moss Chondrus crispus had a long medical history in Europe to treat diarrhea,

urinary disorders and chronic pectoral infections. Dry Laminaria stipes has long been

used in obstetrics to dilate the cervix, as a surgical tool. Chinese used Sargassum

and other Laminariales for treatment of goiter and cancer. Agarophytes like

Gelidium, Pterocladia and Gracillaria are used as laxatives. Another red alga

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(Ptilota) produces a protein (lectin) which preferentially agglutinates human B-type

erythrocytes.

Cosmetics: The use of seaweed extracts in cosmetics is a major international trend at

present. The elements contained in seaweeds act in harmony with the human body,

helping to achieve health, beauty and relaxation. In cosmetology, it is important to

know the biochemical composition and potential use for cosmetics. The extracts can

be used in 2 ways: either as an agent in preparation of products (stabilizer or

emulsifier) or as therauptic agent itself. Alginates of different viscosity serve as

thickening and dispersing agents in cream, jellies, liquid emulsions, lotions, compact

powders, toothpaste etc. They also help in embedding and fixing of aromatic and

fragrant compounds (Levring-Hoppe-Schmid, 1969).

A biotechnological view: Seaweeds contain unique biochemical substances and machinery for their

synthesis. Such chemicals and enzymes are of great interest to pharmaceutical

industries. In the anticipation of future needs, biotechnology will play a key role in

domestication of seaweed and their transformation into crop plants. To meet the

demand of continuous supply of quality seaweeds raw material, it is required to

develop an appropriate cultivation technology, suited to Indian conditions that must

have a blend of traditional knowledge and modern biotechnological tools.

Recent bio-technological methods such as tissue culture, protoplast fusion,

genetic engineering etc. are being employed to produce genetically altered and

improved strains with faster growth rate, altered phycocolloid composition and high

yield. Japan, China and some South East Asian countries have mastered seaweed

cultivation technique for commercial exploitation. Hence, there is an urgent need to

culture the economically viable seaweeds species. However, Eucheuma and

Kappaphycus spp. have been introduced for cultivation in Mandapam, Tamil Nadu.

Introduction of new species, alien to Indian waters and newly constructed strains to

a specific environment warrants impact assessment studies.

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References: Chapman, V.J.Algae as food for man . In: Seaweeds and their uses. The Camelot Press,II nd Edition.1970.86 p. Chapman V .J. and Chapman D.J., 1980. Seaweed as animal fodder, manure and for energy. In: Seaweed and their uses, 3rd Edition, Chapman & Hall, New York. 1980, 30-61. Deshmukhe, G. V. Dhargalkar, V. K. and Untawale, A. G. The Indian Ocean: A perspective Vol-2.(eds.) Desa, E and Sen, R.2001. Dhargalkar, V K and Untawale, A G, Proc. Natl. Workshop on Algal Systems (eds.) Sheshadri, P C., Thomas, M. and Jeejibai, BERK, IIT, New Delhi,1980 63p. Davis, P J, Cellular actions of thyroid hormones, In: The Thyroid. A fundamental and clinical text (eds Bravarmand L E and Utigar R D) J B Lippincott Publ. Philadelphia, 1991, 190-203. FAO, Year book of Fishery Statistics, Commodities, 2000, 90/1 & 90/2. Greville, R. K. Algae Britannicae, 1830. Edinburgh. Hoppe, H. A. Marine algae as raw material, In: Marine algae: A survey of

research and utilization, Ed. Levring-Hoppe-Schmid Cram de Gruyter & Co. Hamburg, 1969.126-127 .

Hoppe, H. A. and Schmid, O. J. Commercial products, In: Marine algae: A survey of research and utilization, Ed. Levring-Hoppe-Schmid Cram de Gruyter & Co. Hamburg, 1969. 288-317. Kirby, R. H. 1953. Seaweeds in commerce, H. M. Stat office, London. Misra, A. and Sinha, S. Algae as drug plants in India. In: Marine algae in pharmaceutical science, Ed: Heinz A Hoppe, Tore Levring, Yukio Tanakia, Walter de Gruyter, 1979. 237-242. Oza, R. M. and Zaidi, S. H. A revised checklist of Indian marine algae. National marine center on algae and marine chemicals. 2001, 296 pp. Smith, H. M. 1905. National Geography. 16:201. WHO, Trace elements in human nutrition and health, Macmillan/Canticle, 1996.

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Table 1: Total capture and culture seaweed production of the world

( million metric tones). CAPTURE CULTURE YEAR RED BROWN GREEN TOTAL RED BROWN GREEN TOTAL

1992 124,374 757,982 53,296 935,652 1,225,961 4,074,378 38,551 5,338,890

1994 141,540 719,709 55,494 916,743 1,705,590 4,514,710 33,906 6,254,206

1996 153,770 783,498 59,420 996,688 1,760,082 4,909,269 28,479 6,697,830

1998 183,890 674,513 61,919 920,322 1,827,780 4,764,915 9,231 6,601,296

2000 270,266 668,966 61,905 1,001,137 1,927,970 4,906,280 33,650 6,867,900

Source: FAO,2000

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Table 2: Seaweed resources along the Indian coast. SR.NO. AREA ANNUAL YIELD

IN TONNES(fresh wt.)

AUTHOR(S)

1. GUJARAT (a) Gulf of Kuchchh (b) Hanumandandi to Vumani(Okha) (c) Adatra Reef (d) Saurashtra Coast

100,000 19,000 650 60 282-608

Chauhan&Krishnamurthy(1968) Bhandari&Trivedi(1975) Sreenivasa Rao et.al(1964) Chauhan& Mairh(1978)

2. MAHARASHTRA (a)Konkan Coast (b)Entire Coast

315 20,000

Chauhan(1977) Untawale et.al.(1979)

3. GOA 2,000 Dhargalkar(1981) 4. KARNATAKA

(a)Entire Coast negligible

Untawale & Agadi(1981)

5. KERALA negligible Nair et.al.(1982) 6. TAMILNADU

(a) Cape Comorin to Colachel (b)Calimere to Cape Comorin (c)Pamban (d)Palk Bay (e)South East Coast (f)Entire Coast

5 66,000 1,000 900 20,535 22,044

Koshy&John(1948) Chacko & Malu Pillai(1958) Varma & Rao (1964) Umamaheshwara Rao (1968) Subbaramiah et.al (1977) Subbaramiah et.al (1979)

7. Andhra Pradesh Figures not availble 8. ORRISA

(a)Chilka Lake 5

Mitra(1946)

9. LAKSHWADEEP ISLANDS

3,645 to 7,598 Subbaramiah et.al(1979)

10. ANDAMAN & NICOBAR ISLANDS (a) Little Andaman

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Gopinathan and Panigrahy(1983)

Source: Compiled from published reports

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Table 6: Uses of Seaweed Phycocolloids. USES PRODUCT FUNCTION PHYCOCOLLOID Food Additives Medicinal-pharmaceutical Cosmetics Other Industrial uses Chemicals

Dairy Products Baked food Sweets Juices and Sauces Breweries Processed meat Frozen Fish Tablets Laxatives Dental mould Metal poisoning Herpes Simplex virus Shampoos Toothpaste Lotions Lipstick Paints Thread making Textiles Paper making Adhesives and starch Pottery Casting and welding rods Analytical seperation and purification of base. Bacteriological media Electrophoresis gel

Gelation,foaming, suspension. Improving quality, controlling moisture Gelation, increase viscosity,suspension Viscosity,emulsifier stabiliser Adhesion Adhesion and moisture retention Encapsulation Indigestibility & lubrication Form retention Binds metal Inhibit virus Interface vitalisation Increases viscosity Emulsification,elasticity & firmness to skin Emulsification,viscosity Viscosity and suspension Glazing Viscosity Sizing and glazing Viscosity and thickening Suspension Coking Chemical reactivity Gelling Gelling

Agar, Carrageenan Agar, Carrageenan Agar, Carrageenan Agar, Carrageenan Alginate,Carrageenan Alginate Alginate Alginate/Carrageenan Alginate- Carrageenan Alginate Alginate Carrageenan Alginate Alginate Carrageenan- Alginate Alginate Alginate Alginate Alginate Agar,Carrageenan, Alginate Agar,Carrageenan, Alginate Alginate Carrageenan- Alginate Agar Agar- carrageenan

Source: compiled from published reports

98

Distribution of Marine Cyanobacteria and their Biotechnological Potentials.

Dr.G.Subramanian, NFMC, Bharathidasan University,

Tiruchirapalli – 620 024.

Coastal marine environments are ecologically and biologically the most

diverse. The organisms either get exposed to wave energies or in protected bays.

Cyanobacteria occupy different ecological niches of marine ecosystem namely open

sea, brackish water, saltpans and mangrooves. An extensive survey of coasts

covering Bhiminipattnam in the east to Goa in the west has resulted in the

enumeration of 195 sp. of 51 genera belonging to 14 families of which 21 sp. were

versatile. The survey of North, Middle, South and Little Andamans had yielded 112

sp. of 40 genera. Interestingly there was no stagnant seawater ponds, backwaters

or saltpans in the islands. The coasts of Andamans were like main land

representing sandy, rocky, corals and muddy shores. Unlike main land and

Andaman Islands, Lakswadweep was essentially of sandy shore with lot of coral

spots and the number of forms enumerated is 115 sp of 39 genera.

This large and diverse group of Gram-negative prokaryotes exhibits the twin

potential of fixing carbon and nitrogen have been only now been explored for

biotechnological purposes. Cyanobacteria have been identified for food and feed

purposes. Potential useful compounds of pharmaceutical value have been identified

from a number of them. Cyanobacteria both as biofertilizer and bioremediators hold

great promise. Cyanobacterial hydrogen production, still in the basic research

stage, promises production of a low cost – non polluting energy source for the next

century. The lecture will deal with the above aspects.

99

Life Histories and Reproductive Strategies in Seaweeds

Geetanjali Deshmukhe Central Institute of Fisheries Eduction

Fisheries University (ICAR) Versova, Mumbai

Marine Algae or seaweeds that belong to lower cryptogams in plant

phylogeny display various types of life histories. The life histories of marine algae

also play an important role in classification also. This also has major application in

the large-scale cultivation of the economically important species towards

understanding the exact stage.

The life history of individual species is a result of the morphology,

environmental conditions – particularly the biological factors, e.g. grazers present in

the ecosystem.

Broadly the life histories can be classified into three categories for Chlorophyceae and Phaeophyceae :

1. Isomorphic alternation of generation

2. Anisomorphic alternation of generation

3. Amorphic alternation of generation

Rhodophycean members, however sjpw

Ulva lactuca (Class Chlorophyceae, Order Ulvales, Family Ulvaceae). Life cycle: Ulva life history is a complicated one (Diagram 1). The sporophytes

and the gametophytes are morphologically similar. The spores and gametes

are similar in size and shape, except that spores are with four flagella and

gametes with only two. They are oblong, tapering towards apex, containing

single plate-like chloroplast with pyrenoid and an eyespot. The spores show

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negative phototactism whereas, the gametes are positively phototactic. Male

and female gametes are isomorphic. Fusion occurs when both the gametes

are motile swimming freely. The zygote contains four flagella and two

eyespots. Both fused and unfused gametes settle down after swimming,

absorb the flagella and germinate. The unfused gametes germinate into the

respective gametophyte. The spores germinate into either male or female

gametophyte. Presence of diploid gametophyte is special feature of Ulva life

history. Parthenogenesis too is common.

DIAGRAM 1: LIFE HISTORY OF ULVA

PARTHENOGENESIS (-/-) (-/-) (Thalli) ( Thalli) (Thalli) zoospore zoospores (-/- 2%) (9%) (- 89 %) (-) (1-2%) (-/-) Ri Ri (+/+) (Thalli) Ri (Thalli) Ri (Thalli) (+/+) zoospores (+/+ 66%) (18%) (+ 16%) zoospore (+/+) (+) (1-2%) PARTHENOGENESIS

zoospore Ri (-) ZYGOTE FUSION Ri (+)

Diploid Sporophyte (+/-)

Gametophyte (-) 1N

Gametophyte

D I P L O I D G A M E T O P H Y

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Gracilaria corticata (Class Rhodophyceae, Order Gracilariales, Family

Gracilariaceae).

Life cycle:

The life cycle of Gracilaria is simple. All the stages in the life history

are macroscopic and isomorphic. Gametophytes are dioecius. Spermatia

when released, are attached to the trichogyne of female carpogyne. The

cystocarps are formed on the female gametophytes as a result of fertilization.

Generally, carposporophyte which is diploid, (Cystocarp) develops on the

haploid female gametophyte. The carpospores (2n) germinate into

tetrasporophyte. Meiosis occurs in the tetrasporangial initial cell and 4 haploid

tetraspores are produced. The tetraspores (n) germinate into male or female

gametophytes in 1:1 ratio.

DIAGRAM 2: LIFE CYCLE OF GRACILARIA

Sargassum illicifolium (Class Pheaophyceae, Order Fucales Family Sargassaceae)

Spermatia (MALE GAMETOPHYTE) (n) T FERTILIZATION E Caropgonium T R Carpogonial branches A with pericarp S P (FEMALE GAMETOPHYTE) CARPOSPOROPHYTE O (n) (2n) R E S TETRASPOROPHYTE CARPOSPORE

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Life cycle:

Sargassum has very typical and simple life cycle. The macroscopic

thalli are sporophytes, on which the gametophytes are developed in reduced

forms called receptacles with numerous conspicuous conceptacles.

Antheridia and oogonia are developed in separate conceptacles in most of

the species. Oogonia are liberated in the seawater upon maturation, but

remain adherent to the conceptacles. An egg is formed in the oogonium.

Antherzoids are released from male conceptacles and get attracted towards

the oogonia. Fertilization takes place out side the conceptacle but inside the

oogonia. Zygote formed develops directly into young plantlet. Life history of

Sargassum is without any alternation of generation; called as

“CYCLOSPORIC”.

DIAGRAM 3: LIFE HISTORY OF SARGASSUM

Ri Ri

ANTHEROZOIDS OOGONIA

MACROSCOPIC SPOROPHYTE

(2N) RECEPTACLES

MALE CONCEPTACLE FEMALE

CONCEPTACLE

FERTILIZATION

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NORI (LAVER)

Porphyra vietnamensis (Class Rhodophyceae, Order Bangiales,

Family Bangiaceae)

Life cycle:

Porphyra life history is a complicated one, consisting two distinctly

heteromorphic generations. The macroscopic one is a gametophytic

generation with either monocious or diocious thallus. The spermatia

released, are attracted towards trichogyne. After fertilization, carospores are

formed in carposporangium. The carpospores are thus diploid and upon

release germinate into a microscopic sporophytes called as ‘Conchocelis’

stage. Another type asexual spores called ‘aplanospores’ are also released

from the macroscopic thalli. These spores germinate into the macroscopic

generation. Aplanospores are smaller in size compare to that of the

carpospores.

The conchocelis stage is very important stage. This microscopic stage

grows on oyster shells. Meiosis occurs in the conchospore initial cell and thus

haploid spores are formed. The released spores called as “conchospores”

germinate into the Porphyra thalli.

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105

The heteromorphic life history- Strategy for Survival

Jane Lubchenco and John Cubit conducted numerous experiments in

an attempt to determine the advantage of heteromorphic life histories. They

arrived at two hypotheses:

• The non-upright morphs (usually boring stages of algae) can survive

through physically harsh seasons while upright morphs are killed off by

stresses such as dessication and high temperatures.

• The two stages are in an attempt to survive the effects of herbivores,

who like to dine on marine algae. Several of the heteromorphic upright

morphs can survive through harsh seasons if they are protected by

herbivores. The non-upright morphs are graze-resistant, and therefore

are more likely to survive over the upright morphs.

The upright and non-upright stages of algae can be mutually exclusive

adaptations to flunctuations in grazing pressure. The upright stages have higher

rates of growth and reproduction when there is very little grazing pressure while the

non-upright stages (boring, crustose phases) are adopted for times of high grazing

pressure.

106

Diversity and Distribution of Calcified algae along Indian coast.

Dr. Vijaya Kerkar

Department of Botany, Goa University, Goa 403 206 E-mail: vijayakerkar@yahoo.com.

ABSTRACT All the algal groups contain a wide variety of forms ranging in structural

complexity from simple unicellular to very complex multicellular types. Owing to

evolution, in due course a few members of these groups developed the ability to

secrete time and are commonly known as “calcified algae”. The carbonate skeleton

functions as a supportive and protective material in many algae.

Calcified algae comprise the oldest fossil known and their remains occur in

rocks of all the ages from precambrian to recent times. Limestone deposits formed

by calcified algae have been associated with petroleum reserves & their relationship

is drawing the attention of many geologists, palaentologists and botanists.

Calcareous algae are actively involved in reef formation. Many of these algae are

known for the production of chemical deterrents.

Calcified algae are scattered in all major groups of marine vegetation. As far

as the marine macroscopic green algae are concerned mention should be made of

Udotea, Halimeda, Acetabularia and Neomeris. Padina is the only calcified brown

alga of Dictyotaceae. Amongst Rhodophyta, members of order nemalionales such

as Liagora, Galaxaura and Actinotrichia are calcified, so also many members of

order corallinales.

Deposition of CaCO3 around or within the cell wall is the general definition of

calcification. Way of lime deposition, amount of calcification differs from group to

group even from genus to genus. Exact mechanism of calcification is still unknown.

The predominant mineral deposit of algae is CaCO3 in the form of calcite and

Aragonite. X-Ray Diffraction and Scanning Electron Microscopy are very useful

techniques in studying mineralogy and surface morphology.

Calcified algae are diverse in tropical seas than that of temperate ones.

Calcified algae make up roughly 10% of the total marine algal flora of India.

107

Altogether 25 genera 88 species are reported from India coast. Oceanic Islands

like Lakshadweep, Andaman, Gulf of Kutchch, Gulf of Mannar, deep water areas like

submerged banks are the areas of calcified algal interest. Very little work has been

done on calcified algae from India. Ambiye Vijaya has worked on taxonomy,

distributiion, surface morphology and mineralization aspects of these algae from

India. Sundarajan has studied Indian nemalionales. Jayagopal (1984) has worked

on taxonomy of crustose corallines of Tamil Nadu coast.

The present lecture deals with diversity and distribution of calcified algae

along Indian coast, Oceanic Islands and deep water areas. Morphological,

anatomical and reproductive characteristics of dominant plants are covered.

Mineralization and surface morphological characters of these algae are focused in

detail with required methodology. REFERENCES Kerkar Vijaya (1994) Minerological studies on calcareous algae. Current Science 66(5):381-382. Kerkar Vijaya & S.D. Iyer (1994) surface morphology of some articulated coralliner from India . Current Science 66(11):868-870. Kerkar Vijaya and A.G. Untawale (1995) Studies on structure and organization of calcium carbonate deposit in algae. Current Science 68(8):843-845. Kerkar Vijaya (2003) Deep water calcareous algae from submerged banks. Seaweed Res , Util (In Press) Desikachary T.V. And et.al.(1998) Rhodophyta Vol II Madras Sci Foundation, 360 pp. Sundarajan,M, (1984) Studies in some Indian nemaliales, Ph.D. Thesis., University of Madras, Madras, 210 pp. Jayagopal, K., (1984) Studies on the crustose coralline algae of Tamil Nadu coast. University of Madras, Madras. 308 pp.

108

Association of Fungi with Marine Algae Seshagiri Raghukumar,

Biological Oceanography Division National Institute of Oceanography,

Dona Paula, Goa – 403 004

The important role that fungi play in association with land plants is well

known. On the contrary, their association with marine plants is insufficiently known.

Fungi are common on marine algae. They show similar associations with algae as

they do with terrestrial plants, namely parasitism, mutualism and saprophytism.

1. Parasites are found in almost all groups of fungi, belonging to both straminipilan

fungi, as well as true fungi. The Oomycetes and Labyrinthulomycetes are the two

groups of stramenipiles that are important in this context. Among the true fungi, the

Ascomycotina are the most important ones. Many mitosporic fungi also cause algal

diseases. Parasitic fungi may be biotrophic or necrotrophic. In the former, the fungi

cause a disease without killing the host tissues. The necrotrophs destroy the host

tissues in advance before colonizing them. Both macro- as well as microalgae

harbour fungal parasites. Several parasites have been described from the Indian

coast. Some of the important ones are the following.

!"The oomycete Pontisma lagenidioides on the green alga Chaetomorpha

media;

!"The oomycete Sirolpidium bryopsidi on the green alga Cladophora sp.,

!"The Labyrinthulomycete Labyrinthula sp. on several green algae;

!"The ascomycete Lindra thalassiae on the brown algae Sargassum sp.

Numerous other examples are known from other parts of the world. One of the most

famous diseases is caused by the oomycete Pythium porphyri, which has often

caused cause devastations to the cultured red alga Porphyra sp. (‘Nori’) in Japan.

These fungi affect the chloroplasts of the host algae. The mechanism of penetration

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has been studied in detail in a disease caused by the oomycetous fungus Ectrogella

perforans on the diatom Licmophora sp. Parasites seem to be extremely common in

marine algae and many apparently remain to be discovered. There is a tremendous

scope to study invasive mechanisms of the parasite in algae, the biochemical

reactions of the host and the effect of such diseases on the ecology and distribution

of algal species.

2. Fungi have often been reported to have mutualistic or commensalistic

associations with marine algae. Three different types of mutualistic symbioses are

known between fungi and marine algae. In the first, fungi and algae are associated

in the form of lichens. Marine lichens may occur attached to rocks in the intertidal

regions. A few have also been found to occur completely submersed in water.

Several non-lichen associations of fungi and algae as obligate mutualistic symbionts

are also known. The fungi Blodgettia and Mycosphaerella are two examples of such

fungi. Finally, associations of mutualistic fungi with roots of marine plants in the form

of mycorrhizae is also possible, although not much work in this area has been

carried out. Salt-marsh plants have been reported to harbour mycorrhizae.

Seagrasses are yet another possible source of mycorrhizal fungi.

3. Fungi may play an important role in the degradation of dead algae. This is

important to the detrital food web, which supports many marine animals. Many

marine algae contain anti-feedant compounds that prevent grazing of animals.

Phenolics and other inhibitory substances in marine algae may also prevent invasion

by fungi. Therefore, these algae enter the food web only after decomposition by

bacteria and fungi, following their death. Thraustochytrids, belonging to the

straminipilan fungi are regularly associated both with living, as well as dead algae.

Marine fungi, both belonging to the true fungi as well as stramenopiles degrade such

detritus. They may obtain substantial biomass on dead brown algae such as

species of Fucus and Sargassum. These fungi may be present both on the surface,

as well as the interior of algal detritus. Thus, for example, the labyrinthulomycete

Aplanochytrium minuta can be regularly isolated in culture from the inner tissues of

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brown algae, such as Padina and Sargassum. They elaborate various degradative

enzymes. As a result , they may alter the biochemistry in such a way that the

detritus becomes more palatable to detritivorous animals. Bacteria and fungi

growing on such detritus may provide essential nutrients to detritivores. One of the

possible essential nutrients is the polyunsaturated fatty acid, docosahexaenoic acid

(DHA) produced abundantly by thraustochytrids.

The regular association of fungi in the form of parasites, mutualistic symbionts

and decomposers points out towards their important role in the ecology of marine

algae. This neglected area of algal and fungal biology needs to be studied in greater

detail.

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Ecological re-engineering in aquaculture: Potential use of seaweeds and macrophytes for nutrient stripping of wastes from aquaculture systems

R. A. Sreepada,

Aquaculture Laboratory, National Institute of Oceanography,

Dona Paula, Goa 403 004 e.mail:sreepada@darya.nio.org

Abstract

The environmental sustainability of aquaculture in general and shrimp farming

in particular has received increasing attention in recent years. Discharge of nutrient

rich effluent from intensive culture systems can contribute to the eutrophication of

receiving waters potentially impacting both natural biota and local culture operations.

Technical innovations have focused on reducing effluent volumes and on discharge

treatment. A growing volume of scientific research and industry experience conflI'm

that water exchange may be reduced or eliminated. The pond microbial community

plays a major role in pond dissolved oxygen dynamics, natural food availability and

nutrient recycling rates. Further research along these lines will improve the

prospects for more profitable and sustainable production technologies. By

integrating seaweeds with fish farming the nutrient assimilating capacity of an area

can be increased. With increased carrying capacity it will be possible to obtain

sustainable yields from aquaculture production units. The potential for using

mangroves and/or seaweeds as filters for wastes from intensive shrimp pond

farming is also discussed. It is concluded that such techniques, based' on ecological

engineering, seems to be promising for mitigating environmental impacts from

aquaculture systems, however more research in this direction is required before

implemented in large-scale.

Background The growth of the aquaculture industry in recent years has made a significant

contribution towards meeting the increasing consumer demand for fish food-

products. Aquaculture expansion continues to outpace growth in capture fisheries

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(Browdy et al., 2001). From 1990 to 1996 aquaculture's contribution to marine

fisheries production nearly doubled from 6 to 11% (New 1999). The high value of

marine shrimp, high consumer demand and relatively short production cycle has

resulted to an explosive growth in this sector of marine aquaculture. However, this

tremendous expansion of aquaculture, particularly the shrimp farming industry over

the past 20 years has been accompanied by degradation of the natural environment

(Beveridge, 1984; Phillips et al., 1986; Gowen and Bradbury, 1987; Folke and

Kautsky, 1989; Beveridge et al., 1991, 1994; Phillips et al., 1991).

As a consequence of continuous strong demand and attractive prices (farm-

gate prices about US $ 5 to 6 per kg), aquaculture production, particularly the shrimp

cultivation in India has experienced fast growth, in particular during the early 1990s

(Hein, 2002). Indian production of cultured shrimp has increased remarkably from

about 30,000 tonnes in 1990 to about 102,000 tonnes in 1999 (Hein, 2002), while

the farm area from 65,000 ha to 140,000 ha (Rao & Ravichandran, 2001). Despite

the large financial benefits generated, the development of this sector has resulted in

a substantial number of negative environmental and social impacts. These include,

(i) conversion of mangroves, (ii) release of waste water (iii) Stalinization of drinking

water wells and paddy fields (iv) destruction of habitats of larvae and juveniles of fish

and crustacean species (v) degradation of coastal wetlands, and (vi) loss of access

to land. However, these impacts occurred, in particular, in the districts with the

highest concentrations of shrimp farms (Hein, 2002).

The general problem in aquaculture systems is that the target crop utilizes

only a small proportion of the feed added to the system. Most farms have relied

upon relatively high rates of water exchange to maintain water quality in production

systems. This has resulted in the release of waste material from uneaten feed,

excess primary productivity and various metabolites, directly into adjacent receiving

waters. In some areas where large scale development of shrimp aquaculture is

coupled with resource-intensive pond management practices, eutrophication of

estuarine waters and/or excessive organic enrichment of the substratum have

occurred. This type of environmental degradation reduces farm productivity and

increases stress on the target crop often leaving shrimp vulnerable to diseases that

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have decimated production in many regions (Browdy and Hopkins 1995; Browdy et

al., 2001).

Environmental management of the aquaculture systems has become a

stumbling block in the sustainability of this industry in the future. Therefore, it is not

surprising that a significant body of current research is devoted in developing the

methods and evolving technologies that improve the long-term viability of marine

shrimp farming. Although several areas have been emphasized including proper site

selection (Clay 1997), prevention of escapement (Browdy and Holland 1998), control

of disease (Lightner et al. 1998), captive breeding of healthy and genetically

improved stocks (Browdy 1998), the reduction of waste output from aquaculture

operations and improving in-pond nutrient recycling is still forms one of the

challenging areas of research for the reduction or elimination of water exchange.

Ecological engineering as a tool for reducing effluents have now gained

renewed interest and many integrated cultivation systems, using different

combinations of seaweeds, bivalves, fish and shrimps have been proposed. The aim

of this paper is to give an overall account on the potential applications of both

macrophytes (seaweeds) and micro algae in nutrient stripping (removal) from

aquaculture systems.

Ecological Engineering in aquaculture systems: The practice of ecological engineering as a tool for reducing effluents from

marine and brackish water aquaculture systems has gained interest very recently.

The main purpose is view aquaculture from an ecological perspective, and where

wastes from one of the components is used as a resource input by others leading to

reduced environmental impacts and increased outputs of fish (shrimp) and

seaweeds (Troell et al. 1999). The studies by Vandermeulen, and Gordin, (1990),

Wang and Jacob, (1991), Buschmann et al. (1994), Neori et al. (1996), Buschmann

et al. (1996), Jamenez del Rio et al. (1996), Brzeskiand and Newkirk (1997) have

shown that waste water from land-based fish and shrimp cultivations is suitable as a

nutrient source for seaweeds and bivalves and that such integration is beneficial

from a nutrient stripping perspective.

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Use of seaweeds as biofilters Methods for treating effluents from enclosed mariculture systems with macro-

algae were initiated in the mid 1970s (Haines, 1975; Ryther et aI., 1975; Roels et aI.,

1976; Langton et aI., 1977; Harlin et aI., 1979). This approach has recently gained

renewed interest (Vandermeulen & "Gordin, 1990; Cohen & Neori, 1991; Neori et al.,

1991; Haglund & Pedersen 1993; Buschmann et aI., 1994, 1996; in press; Jimenez

et aI., 1994; Krom et aI., 1995; Neori, 1996; Noeri et aI., 1996), verifying that

wastewater from intensive and semi-intensive mariculture is suitable as a nutrient

source for seaweed production, and that integration with seaweeds significantly

reduces the loading of dissolved nutrients to the environment. However, in open

culture systems, like fish cage farming, the continuous exchange of water makes

waste disposal difficult to control, and so far, few studies have investigated the

possibilities of integrating seaweeds with such cultures (Hirata & Kohirata, 1993;

Petre II et aI., 1993; Hirata et aI., 1994 a, b; Troell et aI., 1997). Not much

information on the feasibility or application of integrated cultures of seaweeds and

shrimps (He et aI., 1990; Chandrkrachang et aI., 1991; Lin et aI., 1992, 1993;

Primavera, 1993; Flores-Nava, 1995; Enander & Hasselstrom, 1994; Phang et al.,

1996).

Case Studies of integration of aquaculture with seaweeds

i. Land based fish tank cultivation (Troell, et al., 1999) The agarophyte Gracilaria chilensis has been used for removing dissolved

nutrients from an outdoor intensive fish tank culture (Buschmann et aI., 1996; Troell

et al., 1999). The cultivation system consisted of eight circular 8 m3 tanks for salmon

culture (Oncorhynchus kisutch and O. mykiss), from which effluent water was

channelled into decantation tanks for removal of suspended matter. The water was

then lead by gravity to seaweed culture units.

Fish production reached 30 kg m-3 during a 13 month production cycle, and

food conversion could be maintained stable at 1.4 g food g fish-1 production during

the entire cultivation period. Ammonium was the nutrient that increased most in the

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fish effluents, reaching concentrations as high as 500 µg l-1. in spring and summer.

Gracilaria production was 48.9 kg m-2 y-1 and was able to remove 50% of the

dissolved ammonium in winter, increasing to 90-95% in spring.

The production of Gracilaria increased total income by 18% (not including

production costs). If costs for nutrient emission were to be paid for by the producer,

i.e. practicing the 'polluter pay principle', stipulated in the Rio declaration 1992, a

further saving of 4% would be possible through the integration. The final conclusion

from this study and a complementary economical study (Buschmann et al. 2001,

Troell et al., 1999) is that Gracilaria could be used for removing dissolved nutrients

from fish tank effluents, generating economic benefits to the farmers as well as the

society as a whole, and permitting a diversification of the production.

i. Open cage cultivation

Rope cultures of Gracilaria chi/ensis were cocultivated with a coastal salmon

cage farm (producing 230 t a-I) in Chile (Troell et aI., 1997). Gracilaria cultivated at

10m from the salmon cages had up to 40% higher growth rates (specific growth rate

of 7% d-I) than- at 150 m and 1 km distance. The nutrient content of algae was also

higher close to the cages.

Yield of agar per biomass ranged between 17-23% of dry weight, being

somewhat lower closer to the farm but, due to higher growth rates, the accumulated

agar production still peaked close to the fish cages. The degree of epiphytes and

bryozoans coverage was low overall. An extrapolation of the results shows that 1 ha

of Gracilaria, cultivated close to the fish cages, has the potential to remove at least

6.5% of dissolved nitrogen and 27% of dissolved phosphorus released from the fish

farm. For nitrogen this may seem a minor reduction but, because the fish farm

released nearly 16 tons of nitrogen annually, the volume assimilated by the algae is

substantial. Although the size of Gracilaria culture used for the above calculation is

small, it would give an annual harvest of 34 t (d. wt) of Gracilaria, valued at US$

34,000. This Figure is twice that of a Gracilaria monoculture, not integrated with fish

cage farming.

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The conclusions from this study are that both economic and environmental

advantages could be achieved by integrating algal cultivation with fish farming in

open sea systems. A larger cultivation unit would increase nutrient removal

efficiency and profits, . but further studies focusing on full scale cultivation during

different seasons are needed. The high water exchange rates that often characterize

coastal fish farming will be of importance, when integrating seaweeds with fish.

iii. Constructed wetlands

Constructed wetlands for aquaculture waste water treatment is increasing

ecosystems have the ability to remove aquatic pollutants through a variety of

physical, chemical and biological processes. Constructed wetlands have been

shown to have broad applicability as wastewater treatment systems (Hammer,

1989). Schwartz and Boyd (1995) evaluated constructed wetlands for treatment of

channel catfish pond effluents. Suggested advantages of such wetlands include low

cost of construction and operation, elimination of chemical wastewater treatment,

stabilization of local hydrologic processes and contribution of excellent wildlife

habitat. In addition, the constructed wetlands were shown to efficiently remove

potential pollutants from pond water provided that the wetland is large enough for a

2 to 4 day retention time. Organic matter must be removed from the system to

achieve mass conservation. This is accomplished simply by cutting off and removing

vascular vegetation. The system must be designed in such a way that vegetation

cutting equipment can access the site. The area required in constructing a wetland

for channel catfish ponds was calculated by Scwartz and Boyd (1995). These

authors conclude that the disadvantage in using constructed wetlands for treating

aquaculture pond wastes is the large amount of space necessary. However, there

may be some potential in using constructed wetlands to treat effluents from low

exchange production systems or effluents high in potential pollutants associated with

the final stages of pond drain harvests.

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iv. Integration of shrimp culture with halophytes crops

An integrated saltwater aquaculture system for culture of shrimps, useful

halopthytes, and hypersaline Artemia and Dunaliella in sequential ponds, the

drainage eventually being let into salt pans, has been proposed by Brown et al.,

(1999), who have been studying edible halophyte growing in recycling shrimp

effluents. Halophytes such as Salicornia bigelowi have multiple uses: While some

are edible, they can be used as forage for sheep (and goats) and some also yield oil

seeds, from which high quality edible oil can be obtained. Brown & Glenn propose

growing halophytes using shrimp pond effluents for irrigation and also using

abandoned or unused shrimp farms for growing halophytes. The outflow from the

halophyte plots will be hyper saline and so organisms such as Artemia and

Dunaliella could be cultured in this media and the final effluents taken to salt pans

for extracting salt. The suggested integration may specially be applicable to the dry

coastal regions in southern Tamil Nadu, where abandoned/unused shrimp ponds,

salt pans and naturally growing Artemia salina are available.

Sustainable aquaculture in India with particular reference to integration

Adopting a holistic approach to integrated aquaculture systems in coastal

areas would lead to sustainability. Recently, attempts related to the integrated

farming in the mangroves were made in India also (Rajendran and Kathiresan,

1999).

There are vast potentials of integrating in reducing the impacts of the present

aquaculture operations. Integration with seaweed offer great scope and these

systems should be built on sound ecological engineering principles. However, a

solution applied in one type of culture may not be feasible in another and also in

another area. The development of techniques where seaweeds are used as biofilters

is just in its infancy and continued research on ecologically sound production

systems is needed.

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Plant tissue culture, its application and prospects.

Dr.L.H.Bhonsle Cosme Pharma Limited,Bicholim.

What is plant tissue culture: It is a technique of propagation wherein a part of the plant/tissue is used to produce

a complete plantlet true to type to the mother plant under in-vitro conditions. The

property of tot potency of the plant cells is exploited in this technique.

Why Tissue Culture? Tissue culture offers numerous significant benefits over traditional propagation

methods:

• Much faster rates of growth can be induced in vitro than by traditional means.

• It may be possible to multiply in vitro plants that are very difficult to propagate by

cuttings or other traditional methods.

• Large numbers of genetically identical clones can be produced in a small area.

• Seeds can be germinated with no risk of damping off / predation

• Under certain conditions, plant material can be stored in vitro for considerable

periods of time with little or no maintenance.

• Tissue culture techniques are used for virus eradication, genetic manipulation,

somatic hybridization and other procedures that benefit propagation, plant

improvement, and basic research.

• To conserve the disease free stock plants which will be needed for plant

breeding aspects (germplasm collection), especially in case of Crop plants.

• Production and extraction of valuable chemical products (secondary metabolites)

from the cultured cells of the plants rather than directly for the plants grown and

harvested in the field.

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Commercial tissue culture laboratory

1. Bottle washing area – non-sterile

2. 2. Semi-sterile section

• Media preparation room with all the required gadgets

• DM and water distillation unit.

• Autoclave loading area

3. Sterile section

• Autoclave unloading area.

• Media storage.

• Hand and foot wash with attached cloak room.

• Sterile aprons, head gear and face mask.

• Production manager’s office and record room.

• Air conditioned clean rooms.

• Culture transfer room with above facility with LAFs.

• Steripots for continuous sterilization of instruments while at work.

• Culture room with humidity & temperature control and with photoperiod regulation

using artificial lighting facility.

• Dispatch room for washing , grading and packing of ex-agar plants.

• Acclimatization area : Temperature, humidity regulated green house with primary

hardening facility, on growing facility and secondary hardening facility for the

tissue cultured plants.

Stages involved in Plant Tissue Culture

Stage ‘0’ : Mother plant selection

• Careful selection of the mother plant should be done for variety, yield and vigor.

Selection should be made for disease free plants.

• The plants may be pretreated before taking the ex-plants.

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• The stock plants should maintained at relatively low humidity and watered

moderately.

• The part of the plant from which ex-plant is obtained depends on the type of the

culture to be initiated and the purpose of the initiation.

• Growth, morph genesis and rate of propagation in vitro can be improved by

appropriate environmental and chemical pre-treatment of the mother plant.

Stage I : Establishment of the initiated cultures:

The initial step of the micro-propagation is to obtain aseptic culture of the

selected plant material.

• The treatment of the ex-plants with chemicals in order to keep the contamination

low is very important for a commercial laboratory.

• Commonly used surface sterilants are Sodium hypochlorite, Calcium hypochlorite

and Mercuric chloride.

• The surface sterilant should make good contact with all surfaces of the explant.

Penetration can be assisted by immersion in 70 % ethanol, by adding wetting

agents and by agitating the sterilant solution.

• Duration of treatment and concentration of the surface sterilant has to be

standardized after experimentation in order to get good recovery.

• The cultures initiated should be free from contamination.

• The cultures should survive the surface sterilant treatment.

• The cultures should show appropriate reaction ie., growth of shoot tip or

formation of callus on stem piece etc.

Stage II : Multiplication of suitable propagules:

• Multiplication of organs and structures that are capable of giving rise to new

intact plants.

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• Formation of newly derived axillary or adventitious shoots, embyoids, miniature

storage organs or propagative organs.

• Meristematic centers can be induced which will be develop to adventitious

organs upon subsequent transfer.

• The shoots produced can be used as propagules and can be cultured again to

increase the number by division.

Stage III : Preparation for the growth in the natural environment:

• The plants of Stage II are usually small and are not capable of establishing in the

soil or compost.

• The plants from Stage II are rooted before transferring them to green house for

acclimatization.

Stage IV : Acclimatization:

Why acclimatization :

• Shoots developed in culture will be under high humidity and low light intensity

conditions and due to this the leaves will not develop sufficient epicuticular wax.

• They may lose water rapidly if they are moved to external environment directly

which will result in death due to desiccation.

• In the culture, the plants are dependent on carbon source provided through the

medium and are kept in low light intensity. Due to this the photosynthetic

apparatus is not properly developed `when compared to normal plants.

• Hence the plants are gradually acclimatized to natural conditions for over a

period of time to become autotrophic.

• Hardening of ex-agar plants in green house under controlled conditions at first

and then gradually shifting them to the natural environment.

• Humid chambers can be installed with polythene sheets, which can develop RH

levels up to 70 – 80 % inside the tunnel, almost similar to that of the conditions in

the culture vessels and similar light conditions. Here the plants are planted in

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sterilized peat moss with pearlite in cavity trays with proper drainage facility,

which will force the plant from heterotrophic condition to autotrophic mode.

• After keeping them for 30 – 40 days time they are shifted out of the tunnels and

kept for on growing. Here the light intensity is more and humidity lesser when

compared to the tunnel. The temperature and humidity in the green house should

be monitored constantly.

• After 45–60 days in this stage, the plants can be transferred to soil medium for

secondary hardening in open with 50 – 20 % shading depending upon the variety

for 40 –45 days before they are sold.

Tissue Culture medium

• Comprises of inorganic and organic componenets.

• Inorganic – macro and micro elemts

• Organic – vitamins, amino acids and sugar.

• Solidifying agent : agar –agar

• Activated charcoal – to absorb phenolic compounds and also helps in rooting.

• Hormones : auxins, cytokinins, gibberellic acid, absescic acid etc.

• pH adjustment of the medium.

• Sterilization of the medium.

• Storage.

Factors affecting growth

• Genotype of the mother plant.

• Combination of the macro, micro elements and vitamins in the medium and the

growth harmone concentration.

• Presence of phenolic compounds in the medium

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• The pH of the medium

• The moisture content in the culture vessel.

• Presence of toxic gases above the cultures in the medium.

• Culture density in the vessel and the quantity of medium.

• Orientation of the explant.

• The light intensity approx. 1000 lux. and the photoperiod 12hrs.–12hrs. l/d period.

• Temperature and humidity in the culture room and the culture vessel.

• Presence of latent contaminants / in borne contaminants.

• Duration of cultures.

Plant Tissue Culture Techniques and Applications in Plant

Improvement

Seed culture:

• Increasing efficiency of germination of seeds that are difficult to germinate in vivo.

• Production of clean seedlings for explants for meristem culture Organ culture:

• Any plant organ can serve as an explant to initiate cultures Shoot apical meristem culture:

• Production of virus free plants.

• Mass production of desirable genotypes.

• Facilitation of exchange between locations (production of clean material).

• Cryopreservation (cold storage) or in vitro conservation of germplasm - by

suspending the culture in the liquid medium and treating with cryoprotectants and

transferring them to polypropylene ampoules with screw caps and subjected for

cold treatment either by slow freezing, rapid freezing, step wise freezing or by dry

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freezing methods. It can be preserved in this for 12 to 72 months depending

upon the variety.

Somatic embryogenesis: • One major path of regeneration.

• Mass multiplication.

• Production of artificial seeds – somatic embryos enclosed in a protective

coating which results in low-cost-high-volume propagation system.

Organognesis • One major path of regeneration.

• Mass multiplication.

• Conservation of germplasm at either normal or sub-zero temperatures. Enhanced axillary budding:

• Micropropagation. Callus Cultures: • In some instances it is necessary to go through a callus phase prior to

regeneration via somatic embryogenesis or organogenesis.

• As a source of protoplasts and suspension cultures.

• For production of metabolites. Micro-grafting:

• Overcoming graft incompatibility.

• Rapid mass propagation of elite scions by grafting onto rootstocks that have desirable traits like resistance to soil-borne pathogens and diseases.

• To allow survival of difficult to root shoots.

• Development of virus free plants. Genetic transformation:

• Many different explants can be used, depending on the plant species and its favored method of regeneration as well as the method of transformation.

• Introduction of foreign DNA to generate novel (and typically desirable) genetic combinations.

• Used to study the function of genes.

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IN PLANT BREEDING 1. Culturing of organized tissues or meristems, from which whole plant is

regenerated with the aim of maintaining genetic fidelity. The techniques available for

this are:

• Micropropagation – clonal multiplication in vitro.

• Virus elimination – the removal of latent viral infection by meristem culture.

• Embryo rescue – the recovery of hybrid plants in culture, usually from wide

sexual cross, when the endosperm tissue is deficient.

• Ploidy manipulation – reduction of ploidy to the haploid level and doubling it to

give homozygus diploids.

• Germplasm stroage – mother plants for out breeding crops or a wide range of

genetic stocks can be maintained under slow growth conditions in culture, free

from pathogens frost etc.

2. Application of variability which occurs in regenerated plants either as a result of

growing disorganized callus cultures.

• Somaclonal variation : Eventhough most of the somaclonal variations are not

beneficial as they result in morphologically abnormal plants which are of no

useful value but it is possible to obtain variants with apparently normal

chromosome compliments which show useful differences in agronomic

characters. This can be exploited for breeding programs.

• Somaclonal variation results when the cultures are passed through a brief callus

phase and the regenerated plants may show variation which is attributed to the

changes in the chromosome number and the structure of the regenerated

plants.

3. Protoplast fusion:

It is possible to produce somatic hybrid plants by protoplast fusion. The

protoplasts are obtained by dissolving the cell wall. The protplasts of the plants

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of widely different origins can be fused and the heterokaryon can be cultured to

give raise to somatic hybrid plants.

The useful applications of Protoplast fusion technology are:

• The combination of complete genome eg., of sexually incompatible species.

• Partial genome transfer from a donor to a recipient.

• The techniques involved in protoplast fusion may be mechanical method or

induced method – by chemicals and by electrofusion.

4. Production of transgenic plants:

• To introduce foreign genes in to the plant cell.

• Stable integration within the genome of the plant cell.

• The gene products should be expressed in heritable manner.

Using Agrobacterium system as vector.

Why Agrobacterium ?

• It induces tumor formation at the site injury on most of the dicots.

• This is due to its natural genetic engineering ability.

• Agrobacterium species can transfer genes in to the plant cells at the site of injury

resulting in formation of tumor.

• The wild type genes in the Agrobacterium spp. can be excised and replaced with

the gene of choice (disarmed vector) and the transformation can be done under

artificial conditions.

Some of the methods involved in Agrobacterium mediated transformation : • Agrobacterium carrying the desired foreign gene can be engineered in to the

plant cell by directly inoculating at the wound site after removing the top leaves

and apical meristem of the plant of choice under aseptic conditions.

• Since the tumor causing gene is engineered with gene of choice no tumor

formation is seen, instead cells at the wounded site proliferate in to callus.

• The transformed callus is excised and cultured on medium supplemented with an

appropriate combination of growth regulators to give raise to a transformed plant.

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Co-cultivation with protoplast:

• Freshly isolated protoplasts are co-cultured with genetically engineered

Agrobacterium for few days and then transferred to medium containing antibiotics

to eliminate the bacterium.

• Then the regenerating protoplasts are transferred to suitable medium which will

give rise shoots / plants.

Leaf disc infection method :

• The surface sterilized leaf discs are infected with gentically engineered

Agrobacterium for a day and the infected leaf discs are transferred to selective

medium having Kanamycin. Within 3-4 weeks time regeneration of the

transformed plants take place.

5. Direct gene transfer:

DNA can be directly introduced in to the prtoplast by chemical method,

electroporation, micro injection etc. and the transformed protoplasts can be

regenerated to give rise to a transgenic plant.

PRODCUTION OF USEFUL PHARMACEUTICALS

• Commercially valuable chemicals and 25 % of all prescription of pharmaceuticals

are directly from the plant material.

• By cell culture these products can be produced in large quantities without

affecting the plants in their natural habitats.

Factors determining the level of product within cultured cells:

• Variability – somaclonal variation and instability of gene expression

• Metabolic activity within the cultured cells

Challenges to be faced:

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• Establishment of a tissue culture system for synthesizing the desired secondary

product and subsequent selection of the variant cultures that synthesize high

levels of the compound.

• Designing of a bio-reactor system that can manipulate the genetic and

biochemical capabilities of the plant cell to raise production levels.

Production systems:

• Fermenter system – cells grow up to stationary phase and then harvested and

the product extracted.

• Fixed bed system – cells immobilized as multi-cellular aggregates in gels and the

product harvested.

• Mass culture system – cell lines selected for high levels of the compound and

these cells are first grown in a medium which will increase the cell population and

in the second stage the media composition is changed which will result in the

production of compound which is extracted.

• Immobilized cell culture – aggregated immobilized cells in itself can produce

enhanced yields of some secondary compounds and once established can

remain in continuous or semi-continuous production phase for months together.

Problems faced in plant tissue culture:

• Improper selection of the mother plant.

• Genetic variation due to genome modification when the cultures are subjected to

high rate of multiplication and use of inappropriate techniques. Genetic variation

is more in the callus cultures and continual exposure to growth hormones.

129

• Production of Chimeras ie., presence of tissues of two or more types and are

capable of existing together, and their multiplication.

• Vitrification is a morphological abnormality due to excess moisture in the leaves

which is more so in the cultures in liquid medium. The shoots become brittle,

transparent and resemble glass. This is also known as glassy shoot syndrome.

• Loss of vigor due prolonged exposure to artificial conditions.

• Loss due to media Contamination due to improper handling of cultures, improper

sterilization of medium & instruments and due to poor hygienic conditions in the

laboratory.

• Systemic contamination present within the plant system which can not be

penetrated by pre-treatment agents.

Latent contaminants which appear after a considerable period of transfer of cultures,

resulting in heavy loss.

130

Bacterial Association with Marine Vegetation

P.A. Loka Bharathi

NIO,Goa.

Bacterial Association with marine vegetation could be many faceted from

antagonistic to beneficial i.e. it could range from simple epiphytic to mutually

beneficial symbiotic associations or harmful parasitic or pathogenic associations and

are highly variable in space and time. The associations could be direct ie either on

the cell surface or within the cell or indirect in the water or sediment surrounding the

vegetation. The present talk would cover certain examples under these various

heads. It covers epiphytic, entophytic, antagonistic, mutualistic, degradative and

complex associations like cyan bacterial mats. Some points on biotechnological

applications are highlighted together with the future scope for in depth studies on

such associations. The marine flora covered for such associations are

phytoplankton, blue green algae, sea grass, mangroves and phytodetritus Epiphytic Epiphytic flora on sea grass plants The sea grass plants provide a large surface area for algal and bacterial

colonization and growth. Bacterial communities attached to eel grass leaves are

microbial hot spots with high abundances, high activity per volume and rapid turn

over times. Microscopic studies of DAPI stained leaf surfaces and cross section of

leaf segments revealed that the bacteria closest to the leaf surface formed a layer of

uniform sized rods, densely packed together with one end attached to the plant and

the other end facing the surroundings. On older leaves, the bacterial bottom layers

of staining rods was covered with a thick and heterogenous mucus layer where the

bacteria appeared to be more randomly distributed in space. The bacterial

abundance averaged around a minimum of 2 x105 cells cm-2 on tips of old leaves

in late May. Their abundance increased by a factor by 3.2 from newest to the oldest

leaf. Bacterial production estimated from leucine incorporation rates exhibited

131

pronounced seasonal dynamics and varied between a minimum of 0.28 ng C cm-2 h-

1 on new leaves with low abundance in June 1996 and a maximum close to 1ug C

m-2 hr-1 in old leaves. (Tornblom and Sondegaard 1999). Eelgrass leaves are sites of

highly active and dynamic bacterial communities. . Both bacterial biomass and

activity exhibited distinct pattern of distribution with increasing bacterial abundance

and production with increasing leaf age base to tip on individual leaves. The very

high cell specific activity of bacteria indicate a strong coupling between attached

bacterial communities and plant primary production and excretion and shows that

the biofilm on eel grass is a favorable environment for bacterial growth rate.

Epiphytic association on Plankton. A study of sea ice microbial communities showed that epiphytic bacteria grew

at a rate double that of non attached bacteria and were significantly larger

contributing approximately 30% of the total bacterial biomass. About 65% of

epiphytic bacteria were associated with Amphiprora sp. Nitzschia stellata remained

largely uncolonized throughout the study (Grossi et al 1984). Phytoplankton locked

in snow are also associated with bacteria. Chlamydomonas nivalis is present in red

snow as large spherical resting cells. Fine structural studies reveal an abundance of

clear granules in the cytoplasm and occasional starch grains in the chloroplast.

Individual cells display a thick cell wall with a smooth outer surface. Cells may be

surrounded by a loose fibrous network in which encapsulated bacteria are seen. The

bacteria have a characteristic Gram-negative cell wall and constrictive mode of

division. The algal-bacterial association appears to be characteristic of red snow

population (Weiss, 1983).

Epiphytic flora on Mangroves Seasonal distribution of bacteria growing on the leaves, stems and

pneumatophores of Avicennia marina and Sesuvium portulacastrum show that the

lowest population occurred in the pre-monsoon months (February-May) and the

highest during monsoon (June-September) and post monsoon (October-January) on

various parts of these plants. Higher bacterial population was noted on S.

132

portulacastrum . While the roots and stems of both plants supported greater

population of vibrios, the leaf surface yielded more isolates of Flavobacterium.

Epiphytic to Endophytic Barnabas (1992) describe the invasive bacteria occurring within tunnels in the

walls of cells. Endophytic bacteria have been observed living in the cells and within

the wall of different species of algae. Dense bacterial community covering the tips of

mature green leaves of Thalassodendron ciliatum were often embedded in an

amorphous matrix and were frequently arranged with their long axis at right angles

to the leaf surface. Parts of the outer wall and cuticle of the cells were disrupted and

bacteria with marked cellulolyic activity could be seen penetrating into the walls.

The penetration of bacteria into the wall of Nitophyllum punctatum cells has been

described by (Garcia-Reina et al, 1988).The bacteria, adhere, erode, and then

invade and reproduce. Endophytic bacteria isolated from Nitophyllum and some

epiphytic ones, cultivated in agar, have been revealed to be agarolytic. (Ghirardelli,-

1986). Some even think that endophytic bacteria may play a role in callus induction

and regeneration

Occurrence of endophytic bacteria in siphonous algae. Endophytic bacteria are harboured inside the thallus of Halimeda tuna and

Udotea petiolata, between the siphons and within coenocytes filaments. Most of

them are generally located with in the vacuole and, preferentially, very near the

chloroplasts (Mariani-Colombo,1972). Marianai, and .; Favali,(1985)observed that

when unwounded and wounded thalli of the siphon us green alga Udotea petiolata

were incubated for 49 h with 35S sulphate to estimate the possible differences in the

cellular localization and amount of uptake of the radioisotope. A limited 35 S-

sulphate incorporation in the thalli was observed, whereas endophytic bacteria in the

thalli, cytoplasm, vacuole and chloroplasts were the most heavily labeled.

133

Inhibitory/Antagonisitc Bacteria -------------# algae

Marine algicidal bacteria kill phytoplankton by producing killer substances.

These bacteria significantly influence the population dynamics of phytoplankton and

contribute to the sudden termination of red tides. The algicidal bacteria show

inhibitory activity against a wide range of different algae. However, motility and

thecae of phytoplankton contribute to defense against the killer bacteria (Imai, 1997).

Bacteria----#### phytoplankton Bacteria are also known to inhibit phytoplankton. Pseudoalteromonas

peptidysin have algicidal effect on harmful algal bloom species of the genera

Chattonella, Gymnodinium and Heterosigma. These bacteria could play an

important role in regulating the onset and development of harmful algal blooms.

(Lovejoy et al, 1998). Yet others like, Alteromonas colwelliana inhibit the growth of

the diatom Chaetoceros calcitrans. Gliding diatoms are used for screening for

bacterial inhibition (Kim et al, 1999)

Phytoplankton #### bacteria The inhibition can also act the other way i.e. the phytoplankton could prevent

the growth of bacteria. Antibacterial activity of marine diatom Skeletonema costatum

has been effectively used for controlling the growth of either Vibrio anguillarum or

Vibrio alginolyticus identified as pathogens in aquaculture farms and commercial

hatcheries (Naviner et al, 1999; Rico Mora et al, 1998).

Beneficial/stimulatory effect. On the contrary the interactions between the phototrophic and bacterial

component could also be stimulatory. Growth-promoting bacteria are used for

developing stable mass culture of marine micro algae. Flavobacterium sp was

found to promote growth of marine diatom Chaetoceros gracilis in the axenic culture

134

condition. The specific growth rate and maximal cell density were determined in

treated cultures lasted longer (Suminto and Hirayama, 1997).

Diatoms are also used as live food for planktonic larvae of sea urchin and

bivalves. Chaetoceros ceratosporum grows better in the presence of certain strains

of bacteria. The positive effect of bacteria is not only with planktonic species of

diatoms but also for attached forms. The benthic diatom Nitzschia sp was stimulated

by bacterial film of Alcaligenes on the surface of the substratum. However, a

flavobacterium species isolated from sea water towards the end of the bloom had a

strong algicidal effect on the red tide plankton Gymnodinium mikimotoi Thus

bacterial strains and their effects could be important factors that influence stable

mass culture micro algae grown for feed. (Fukami et al, 1997)

Mangroves Even mangroves can be positively influenced by certain groups of bacteria.

Terrestrial plant growth –promoting bacteria have been used in the growth of black

mangrove seedling. Halo tolerant plant growth promoting bacterium Azosprillum

halopreferans or Azospirillum brasilense produced heavy colonization of the root

surface. A halopreferens colonized the root surface whereas A. brasilense

population covered the entire root (Puente et al, 1999).

Bacterial association also meet the nitrogen requirement of the mangrove

plants. Nitrogen fixation by blue-green algae (cyan bacteria) associated with

pneumatophores of Avicennia marina , and wet and dry surface sediments was

investigated in the Beachwood Mangrove Nature Reserve by means of the

acetylene reduction technique. Significant dark rates of acetylene reduction and

stimulation of the process by sucrose in association with the pneumatophores

indicated that bacteria may also be contributing to Acetylene reduction in this habitat

(Mann and Steinke, 1993).

Chemo taxis is responsible for establishing specific nitrogen-fixing cyan

bacterial-bacterial association. Pseudomonads were shown to attach specifically

to heterocyst and heterocyst-vegetative junctions of Anabaena oscillaroides when

135

introduced into axenic N-fixing cultures of the cyan bacterium. The association

enhanced N-fixation and the positive chemo taxis was more marked during active

N-fixing periods. . (Paerl, Gallucci, 1985). It has been suggested that the

excretory products A. oscillaroides could be responsible for positive chemo tactic

responses. Aquatic bacterial-algal and bacterial-particle associations occur

sporadically and are heterogeneously distributed in time and space perhaps

because of these associations.

Biodegradation Marine bacterial assemblages accelerate dissolution of diatom silica.

Bacteria-mediated silicon regenerated rates varied with diatom type and bacterial

assemblage and could critically control diatom productivity and the cycling and fate

of silicon and carbon in the ocean. When marine diatoms were grown axenically

and in the presence of a bacterial isolate, showed mixed results. High growth and

enhanced hydrolytic ectoenzymes activities in the presence of algae and polymer

particles led to high bacterial remineralisation of organic nutrients increasing

phytoplankton growth Bidle and Azam (1999). However, bacteria compete with

phytoplankton for nutrients and can inhibit algal growth under environmental

conditions. Thus, changes in eutrophication and pollution can alter the bacteria-

phytoplankton interactions, which influence the flux and cycling of nutrients and

carbon at both micro and global scale.Grossart, 1999).

Particle associated bacteria (PAB) Particles in estuary is composed of decaying macrophytes and phytoplankton

among other things. Bacteria that colonize such phytodetritus dominated

aggregates in estuaries form a significant fraction of total bacterial population. The

density of associated bacteria, their productivity and activity is higher than free living

counterparts (DeSouza,et al, 2003). Bacterial association increase the food value of

detritus by increase in levels of protein and also digestibility due to the elaboration

of various enzymes by associated bacteria.

136

Cyanobacterial mats Cyanobacteria were the first oxygen evolving phototropic organisms and were

responsible for the conversion of the atmosphere of the earth from anoxic to oxic.

They comprise a large and heterogeneous group of oxygenic phototropic bacteria.

They represent one of the of the major phylogenetic lines of bacteria and show a

distant relationship to Gram +ve bacteria. Microbial mats are formed in a variety of

environments, especially in hot springs and shallow marine basins and are dynamic

systems where photosynthesis occurring in the upper layers of the mat is balanced

by decomposition from below. The mats are layered microbial communities usually

containing cyanobacteria in the upper most layer, an oxygenic phototrophic bacteria

in the subsequent layers. (until the mat becomes light-limited and

chemoorganotrophic, especially sulfate-reducing bacteri in the lower layers.

Stromatolites are fossilized microbial mats consisting of layers of filamentous

prokaryotes containing trapped sediment. While old stromatolites are composed of

an oxygenic phototropic bacteria, the modern ones are composed of filamentous

cyanobacteria. Fenchel and Kuehl (2000) were able to quantify the vertical

distribution of major groups of organisms in solar salt lake.

Biotechnological Application We have seen earlier in some of the examples how of some bacteria are

important in producing stable algal biomass for feed. Yet others are useful for

controlling fouling algae. Associations can be used in the bioremediation of water

rich in sulfide and organic matter. Other associations could be useful as

bioindicator. Symbiotic micro flora of the brown algae from the genus Laminaria

serve as a useful bioindicator of the ecological state of coastal Laminaria

biocoenoses.(Dimitrieva, and Dimitriev, 1996) . The composition of the epiphytic

micro flora of cultivated Laminar a showed the appearance and dominance of the

genus Altermonas bacteria and disappearance of higher actinomyces. The genus

Altermonas bacteria produced various hydrolases and inhibited bacterial symbionts

of Laminaria from natural beds. The productivity of cultivated Laminaria was found to

decline with time. Diseases, colonized by various fouling organisms, affected the

137

algae and practically no commercial fish species were any longer recorded on the

plantations. Oil degrading consortia Another application is in the use of these associations for oil degradation.

This paper reports on hydrocarbon-degrading microbial consortia immobilized in

biofilms on gravel particles in the intertidal zone of the Arabian Gulf coast. These

microorganisms contribute to the self-cleaning of the coasts and, in addition, could

potentially be used for cleaning oily industrial waste before its disposal in the open

environment. Each gravel particle was found coated with about 100 mg biofilm of

blue-green biomass. The predominant phototrophs were the cyanobacteria

Dermocarpella and to a lesser degree Lyngbya sp. The most dominant hydrocarbon-

degrading bacterium in this consortium was Acinetobacter calcoaceticus; minor

bacteria included Micrococcus and nocardioforms. The biofilm-coated gravel

particles were used in 5 successive cycles of purification of oily seawater. This

immobilized micro flora was efficient during all cycles in hydrocarbon consumption.

In contrast, bacteria adhering to biomass-uncoated gravel particles brought about

hydrocarbon degradation in the first few cycles, but then gradually lost their cleaning

potential, apparently due to their successive washing out from the particles during

successive cycles (Radwan and Al Hassan (2001). Naturally occurring

photosynthetic and non photosynthetic associations have also been reported to

participate in degrading oil slicks. (Sorkhoh et al, 1992).

Syntrophic associations between marine plants and bacteria can form new avenues

for explorations. They form an interesting study in themselves as they exist in such

close association in nature. Such synergy could be explored for gainfully harnessing

their activities or their metabolic products. Naturally occurring consortia or artificially

composed could also be used for bioremediatory measures such as containment of

excess sulfide, degrading hydrocarbons or other pollutants.

138

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nitrogen-fixing cyanobacterial-bacterial association. SCIENCE-WASH.. vol. 227, no. 4687, pp. 647-649

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INTERTIDAL SEAWEED ECOLOGY

Prof. B. B. Chaugule, Department of Botany

University of Pune, Pune 411 00 7

E-mail – chaugule@unipune.ernet.in

Intertidal region is an extension of land into the sea which is covered during high

tides and exposed during low tides. The periodic rise and fall of sea level that results from

the gravitational attraction exerted on the earth by the moon and to lesser extent by the

gravitational pool of the Sun is ‘ the tide’.

Tides are complex because of – 1) The movement of the man in relation to the

earth equator. 2) Change in the position of the moon and the sun with respect to the

earth. 3) Uneven distribution of the water on the earth surface and 4) Irregularities in the

configuration of the ocean basin.

Because of these variable tides vary. e.g. In the Bay of Fundy, between New

Brunsck and Nova Scotia, they are over 12 meters high but along the coast of the

Mediterranean Sea they are virtually unnoticeable.

Spring tides are high tides that occur when the moon is full or new while neap

Tides occur when sun and moon make some angle with the earth. The tides exhibit tidal

cycles. The types of tidal cycle are 1) Diurnal tides 2) Semi diurnal tides 3) Mixed tides.

The environmental factor operating on the organisms of the intertidal region are

as under.

Tidal cycle is responsible for periodic exposure of the intertidal region. Therefore

the organisms in the intertidal regions are subjected to desiccation and insolation

depending upon the prevailing ambient temperatures. Wave actions likely to lead

1

mechanical damages to organisms and substrata. Rainwater causes reduction in salinity

particularly during low tides. In tidal pools, salinity increases due to evaporation.

The Indian coast is characterized by the mixed tides and narrow intertidal region

and could be divided into a) Sandy coast b) Muddy coast and c) Rocky coast

The rocky coasts are favorite sites for the seaweeds to grow as rocks are

stable substrata and provide space for spores to settle and germinate. There are large

number of studies on the intertidal region with respect to zonation patterns. Size of the

zone depends on slope, tidal range and exposure to waves. On the basis of thirty years of

2

extensive studies on the rocky shores of Britain, North America, South Africa, the Indian

Ocean and Australia, Stephenson and Stephenson (19949, 1972) published a classical

paper on the universal features of zonation between tide marks, on rocky coasts. In this

paper Stephenson and Stephenson suggested that the certain features of zonation were of

such wide spread occurrence, in the world, that may even be universal. In addition they

also proposed a scheme to define zones of open rock surfaces and terminology applicable

to the wide spread zones. According to Stephenson’s zonation of the open rock surfaces

exposed to degrees of wave action, intermediate between maximal and minimal is

regarded as the standard, from which deviation may be most conveniently recognized.

Further the shores tends to show following belts from above downwards

1) Supralittoral zone: This zone is above the tide marks and extending

upto the limits of the influential spray or to the land vegetation.

2) Supralitteoral fringe: This is a belt from the upper limit of barnacles (in

quantity) to the nearest convenient land mark above this. High water of

spring tides invades the lower part of this zone.

3) Mid littoral zone: This zone extends from upper limit of barnacles (in

quantity) down to the upper limit of the zone below. This zone experiences

alternate period of exposure and submersion.

4) Infralittoral fringe: This is a belt between upper limits of any

convenient dominant organism (e.g. Laminaria, Pyura), to extreme low

water level of spring tides or to the lowest level ever visible between

waves. This zone uncovers only during extreme low tides and some times

only in calm weather

3

5) Infralittoral zone: This is the zone from extreme low water of springs to

a depth which has yet to be settled. It may be to the edge of the continental

shelf or to the lower limit of seaweed vegetation.

According to Doty (1946) shoreline communities can be studied in reference to

physical parameters rather than the biological parameters. He modified version of the

concept of critical tide level introduced by Colman. According to Doty’s hypothesis there

exist zone boundaries and critical tide levels

According to Krishnamurthy (1967) zonation along the Indian coast depends on

1) Nature of tides in any given place 2) Extent of intertidal zone3) Physiographic factors

in the intertidal zone. 4) Topographic of the shown particularly gradient.

According to him physiographic factors pose greater effect on the zone.

Krishnamurthy further states that because of geographical, climatic and

physiographic factors the Indian coast harbor only sublitterol algal communities with

practically no zonation.

The zonation pattern of the marine algae at Colaba – Bombay studied by us shows

following distribution pattern

Supralittoral zone: This zone exits for very short while in late monsoon (August –

September) period. The only alga in this zone is Enteromorpha flexuosa. While

Porphyra occupies the region even below during monsoon.

Supralittoral fringe: This zone is characterized by Littornia and algae like Microcoleus

and Caloglossa. The upper limit of Littornia however coincides with the extreme

high water level of spring tides.

4

Mid littoral zone: It is a zone of Barnacles and Balanoids. Algae occurring in this

zone are Chaetophora and Porphyra (only during monsoon).

Infralittoral fringe: In this zone there are more algae than all other zones. Algae found

in this zone are Enteromorpha, Ulva, Centroceras, Gelidium, Hypnea, Gracilaria,

Padina, Spathoglossum, Caularpa. Rhodymenia and Champia occurring in the

zone also extend in the zone below. Ostrea, an edible oyster is a characteristic

animal in this zone.

Infralittoral zone: It is a zone that is never exposed. Algae characteristic only of this

zone include Sargassum and Scinaia.

Factors controlling distribution and zonation pattern of the organisms are-

A) Physical factors

1) Light

a) Intensity (varying with altitude, tidal exposure, cloud cover, shore

shading, biological overshading)

b) Quality (varying with water depth, transparency, tidal amplitude)

c) Periodicity (daily, seasonal)

2) Substrate

a) Solidarity (bedrock, cobble, gravel, sand mud)

b) Texture (penetratibility or solubility for attachment)

c) Porosity (water - holding capacity)

d) Position

a') with regard to water availabity (tidal flooding, wave wash,

splash, spray, seepage, tidepool retention)

b') with regard to wave shock or disturbance

c') with regard to ice action or cobble scour

e) Solubility and erosibility

f) Color (with regard to intertidal heat absorption, radiation and

reflection).

5

g) Chemical composition

3) Temperature

a) Seawater temperature

a') annual variation

b') duration of maximum and minimum

c') diurnal variation

d') stratification; thermocline position with respect to tides,

mixing of nutrients, etc.

b) Air temperature during intertidal exposure

a') annual variation

b') duration of maximum and minimum

c) Direct heat of insolation (complete exposure; tidepool exposure)

4) Relative humidity (with respect to algae subject to exposure)

a) Seasonal variation in conjunction with exposure

b) Duration of minimum coincident with maximum exposure

temperature

5) Rain

a) Seasonal extent coincident with tidal exposure

b) Maximum duration

6) Pressure (mainly significant with regard to effect of tidal amplitude on

attached seaweeds bearing air vesicles)

B) Chemical factors

1) Salinity

a) Annual variation from runoff

b) Tidal fluctuation of the halocline

c) Maximum concentration from evaporation during exposure

2) Availability of dissolved oxygen during dark- hour respiration

3) Availability of nitrogen, phosphorus and other essential metabolic

substances.

4) Availability of free carbon dioxide for photosynthesis

5) pH (mainly significant in confined pools subject to marked increases

6

during active photosynthesis)

6) Pollution

a) By natural marine organisms

b) By waste products of human activity

C) Dynamic factors

1) Water movement

a) Surf

b) Ocean currents

c) Tidal fluctuation and current

d) Maximum severity of annual storm or hurricanes

e) Upwelling

f) Extent of surface chop vs. calm.

2) Tidal exposure (period and amplitude)

3) Tidal rhythm (with respect to release of reproductive bodies)

4) Wind (with respect to coincidence with exposure)

D) Biological factors

1) Grazing pressure

2) Fungal and microbial activity

3) Competition for substrate

4) Protective cover against desiccation during exposure

5) Light restriction by overgrowth (either by macroscopic or microscopic

forms)

6) Availibity of host plants or animals for obligatory epiphytic, endophytic,

epizootic, endozootic and parasitic algae.

7) Human impact

a) Fisheries

b) Marriculture

c) Pollution

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Some selected References:

Dawes, C. J. 1981. Marine Botany A Willy Interscience publication. pp. 628

Dawson, E. Y. 1966 Marine Botany an Introduction, Holt, Rinehart and

Winston, Inc. pp. 371.

Krishnamurthy, V. 1967. Some general considerations on zonation of marine

algae on the Indian coasts. Proc. Sem. Sea Salt and Plants,

Bhavnagar, 219 – 223.

Round, F. E. 1981 The ecology of algae, Cambridge University Press, pp. 653

Stephenson, T. A. and Stephenson, A. 1972. Life between tide marks and rocky

shores. W. H. Freeman and C. San Francisco, pp. 425.

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