Biodiversity

16.02.07

BiodiversityBiodiversity refers to the variety and variability among

all groups of living organisms and the ecological

complexes of which they are a part

Units of Biodiversity

1)Genetic diversity

2)Species diversity

3)Ecosystem diversity

Genetic diversity• Genes are the basic units of hereditary information

transmitted from one generation to other

• The genes found in organisms can form enormous number of combinations each of which gives rise to some variability

• When the genes within the same species show different versions due to new combinations, it is called genetic variability

• For eg, all rice varieties belong to the species Oryza Sativa, but there are different varieties which differ in their shape, size, aroma due to variations at the genetic level

Species diversity• This is the variability found within the

population of a species

• The richness of species in an ecosystem is called species diversity

• The total number of living species is in the range of 10-50 million. But till now only about 1.5 million species have been actually described and given scientific names

Ecosystem diversity

• An ecosystem develops its own characteristic community of living organisms depending upon the availability of abiotic resources, environmental conditions and other factors

• For eg, a pond possess different sets of flora and fauna as compared to the river ecosystem

• This diversity has developed over millions of years of evolution and is of great value that must be kept intact

Biogeographical classification of India• India has different types of climate and topography in

different parts of the country and these variations have induces enormous variability in flora and fauna

• India has a rich heritage of biological diversity and occupies the tenth position among the plant rich nations of the world

• Based on the biodiversity, climate, topography India has been classified into 10 biogeographic zones

India’s biographic zonesS.No Biographic Zone Biotic Province

1 Trans –Himalayan Upper regions

2 Himalayan North-west Himalayas, West Himalayas, Central Himalayas, East Himalayas

3 Desert Kutch, Thar, Ladakh

4 Semi-arid Central India, Gujarat-Rajwara

5 Western Ghats Malabar Coast, Western Ghat mountains

6 Deccan Peninsula Deccan plateau south, Central plateau, Eastern plateau, Chotta Nagpur, Central highlands

7 Gangetic plain Upper gangetic plain, Lower gangetic plain

8 North-East India Brahmaputra valley, North-Easter hills

9 Islands Andaman islands, Nicobar islands, Lakshadweep islands

10 Coasts West coast, East coast

Biogeographical classification of India

Value of biodiversityThe multiple uses of biodiversity value has been

classified by McNeely et al in as follows:

1) Consumptive use value

2) Productive use value

3) Social value

4) Ethical value

5) Aesthetic value

6) Optional values

7) Ecosystem service value

Consumptive use valueThese are direct use values where the biodiversity product can beharvested and consumed directly e.g. fuel, food, drugs ,fibre etcFood:A large number of plants are consumed by human beings as food. About90% of present day crops have been domesticated from wild tropicalplants.Drugs and medicines:75% of the world’s population depends upon plants or plant extracts formedicinesPenicillin-Penicillium Quinine-Bark of cinchonaVinblastin and Vincristine-CatharanthusFuel:Forests have been used since ages for fuel wood. Fossil fuels are alsoproducts of fossilized biodiversity

Productive use values• These are commercially usable values where the

product is marketed and sold

• It may be lumber, wild gene resources

• Animal products like tusks of elephants, musk from musk deer, wool from sheep

• Despite international ban on trade in products from endangered species, smuggled hide, fur, tusks worth millions of dollars are being sold

Social value• Values associated with the social life, customs,

religion and psycho-spiritual aspects of people

• Many of the plants are considered holy and sacred in our country (Tulsi, Peepal, Mango)

• Many animals like cow, snake, bull, peacock also have significant place in our psycho-spiritual arena and thus hold special social importance

Ethical value• Ethical values is also sometimes known as

existence value.

• It involves ethical issues like “all life must be preserved” and the concept of “Live and let live”

• The ethical value means we may or may not use a species, but we feel the existence of the species is necessary

Aesthetic value

• Great aesthetic value is attached to biodiversity

• Stretches of barren lands with no signs of visible life is not a pleasant sight

• Eco-tourism is based on the aesthetic value of biodiversity

• Ecotourism is estimated to generate about 12 billion dollars of revenue annually

Optional values

• These include the potentials of biodiversity that are presently unknown and need to be explored

• For eg, there is a possibility that we may have potential cure for AIDS or cancer existing within the depths of marine ecosystem, or tropical ecosystem

Ecosystem service valueIt refers to the services provided by ecosystem like

1) Prevention of soil erosion2) Prevention of floods3) Maintenance of soil fertility4) Cycling of nutrients and water5) Fixation of nitrogen6) Role as carbon sinks

Different categories of biodiversity value clearly indicatethat ecosystem, species and genetic diversity haveenormous potential and a decline in biodiversity will leadto huge economic, ecological and socio-cultural losses

India as a mega-diversity nation• India is one of the 12 mega diversity countries in the

world

• The ministry of Environment and Forests, records show 47,000 plant species and 81,000 animal species

• A large proportion of the India Biodiversity is still unexplored

• Due to diverse climatic conditions there is a complete rainbow spectrum of biodiversity in our country

Distribution of species in IndiaGroup-wise species distribution

Plants Number Animals Number

Bacteria 850 Lower groups 9979

Fungi 23,000 Mollusca 5042

Algae 2500 Arthropoda 57,525

Bryophytes 2564 Fishes 2546

Pteridophytes 1022 Amphibia 428

Gymnosperms 64 Reptiles 1228

Angiosperms 15,000 Birds 204

Mammals 372

Reasons for India as a mega-diversity nation

1)Endemism

• Species which are restricted only to a particular area are know as endemic.

• India shows a good number of endemic species. About 62% amphibians and 50% lizards are endemic to India.

• Western ghats are the site of maximum

endemism

Reasons for India as a mega-diversity nation

2)Centre of origin

• A large number of species are know to have originated in India

• Nearly 500 species of flowering plants have their origin in India

• India has been the center or origin for 166 species of crop plants and 320 species of wild relatives of cultivated crops

Reasons for India as a mega-diversity nation

3)Marine diversity

• The coastline of our country exhibits a rich biodiversity

• Along 7500 km long coastline, in the mangroves, coral reefs back waters etc, different species are found

• The marine diversity is rich in mollusks, crustaceans and several species of mangrove plants and sea grasses are found

Hotspots of biodiversity• Areas which exhibit high species richness as

well as high species endemism are termed as hotspots of biodiversity

• To qualify as a biodiversity, a region must meet two strict criteria:

1)It must contain at least 0.5% or 1,500 species of vascular plants as endemics,

2)It has to have lost at least 70% of its primary vegetation

Global hotspots of biodiversity1)Tropical Andes 15)Caucasus

2)Mesoamerican forests 16)Sundaland

3)Caribbean 17)Wallacea

4)Brazil’s Atlantic forest 18)Philippines

5)Western Ecuador 19) Eastern Himalayas

6)Brazil’s Cerrado 20)South-central China

7)Central Chile 21)Western-Ghats Sri Lanka

8)California Floristic Province 22)South-western Australia

9)Madagascar 23)New Caledonia

10)Eastern Arc and coastal 24)New Zealand

forest of Tanzania/Kenya 25)Polynesia/Micronesia

11)Western African Forests

12)Cape Floristic Province

13)Succulent Karoo

14)Mediterranean Basin

Salient features of Indian HotspotsA)Eastern Himalayas:

• The eastern himalayan region encompasses Bhutan,

North east India, and south, central and eastern Nepal

• The region is home to 163 globally threatened species including Asia’s

Three largest herbivores –the Asian elephant, the greater one horned rhinoceros, and the wild water buffalo

Carnivore-The tiger

Birds-Vultures, Storks and hornbills

• Out of the world’s recorded flora, 30%are endemic to India of which 35,000 are in the Himalayas

Salient features of Indian HotspotsB)Western Ghats

• It extends along a 17000 sq.km strip of forests in Maharashtra, Karnataka, TN and Kerala and has 40% of total endemic plants

• The major centers of diversity are Agastyamalai Hills and Silent valley-the New Amambalam reserve basin

• It is reported that only 6.8% of original forests are existing today while the rest has been deforested or degraded

Threats to Biodiversity• Extinction or elimination of a species is a

natural process of evolution.

• The process of extinction has become particularly fast in the recent years of human civilization

• One of the estimates puts the figure of extinction as 27/day

• If the present trend continues we would lose 1/3rd to 2/3rd of our current biodiversity by the middle of 21st century

Loss of Habitat• Destruction and loss of natural habitat is the single largest

cause of biodiversity loss

• Billions of hectares of forests and grasslands have been cleared over the past 10,000 years for conversion into agricultural lands, pastures, settlement areas or development projects

• Thousand of species have perished due to loss of their natural habitat

• A phenomenon known as habitat fragmentation have resulted in loss on many singing birds

• As a result of human intervention marine biodiversity is under serious threat due to large scale destruction of the fragile breeding and feeding grounds

Poaching• Illegal trade of wildlife products by killing

prohibited animals, is a threat to wildlife

• Despite international ban on trade in products from endangered species, smuggling of wildlife items like furs, hides, tusks, etc continues

• The worse issue is that for every live animal that gets into market, about 50 additional animals are caught and killed

Man-wildlife conflicts• When wild life causes immense damage and danger

to man , the conflict occurs

• In retaliation, the villagers electrocute or kill the animals which sometimes exceed poaching

Causes:

1) Dwindling of habitats and human encroachments into the forest areas

2) The wild life corridors through which animals used to migrate seasonally have been used for human settlements and hence animals attack the settlements

Causes of man-animal conflict

3) The stopping of cultivation of paddy, sugarcane etc.. within the sanctuaries have led the animals to stray out

4) The compensation paid by the government in lieu of the damage caused to the crops is not adequate and the agonised farmer gets revengeful and kills the wild animals

5) Ususally the ill, weak and injured animals have a tendency to attack man

Classification of speciesExtinct species- A species is said to be extinct when it is

not seen in the wild for 50 years at a stretch. Eg Dodo,

passanger pigeon

Endangered species-When the number has been reduced

to a critical level or whose habitats have been drastically

reduced and when not protected and conserved they are

endangered species

Rare species-Species which are not endangered at

present, but are at risk are categorised as rare species

Endemic species-Species which are restricted to a

particular area is called as endemic species

Endangered species• These are species which if not protected are likely

to become extinct in near future

• The International Union for Conservation of Nature and Natural Resources(IUCN) publishes the Red Data Book which includes the list of endangered species of plants and animals

• In India nearly 450 plant species , 150 mammals and 150 species of birds have been listed as endangered species

Few endangered species of India

1) Reptiles :Green sea turtle, Tortoise, Python

2) Birds: Peacock, Great Indian Hornbill, Pelican, Siberian White Crane

3) Carnivorous mammals: Indian wolf, red fox, tiger, lion, red panda, leopard, striped hyena, desert cat, dugong

4) Primates: Capped monkey, golden monkey, nilgiri langur, hoolock gibbon

5) Plants:species of orchids, rhododendrons Santalum, Cycas beddonei etc

Endemic species of India

• India has two biodiversity hotspots and thus possesses a large number of endemic species

Endemic flora-Sapria himalayana, Uvaria lurida, Nepenthes Khasiana,

Pedicularis perroter etcEndemic animals-Varanus, reticulated python,

Indian Salamander, Viviparous toad, nectophhryne

Conservation of biodiversity• The enormous value of biodiversity due to

their genetic, commercial medical, aesthetic importance emphasize the need to conserve biodiversity.

• There are two approaches of biodiversity conservation– In situ conservation

– Ex situ conservation

In Situ conservation• This is achieved by protection of wild flora and fauna

in nature itself.eg Biosphere reserves, National parks, Sancturies, Reserve forests etc

• The Biosphere reserves conserve some representative ecosystems as a whole for long term in situ conservation. Gulf of mannar, Nilgiri, Sunderbans, Nanda devi are few biosphere reserves

• A National park is an area dedicated for the conservation of wildlife along with its environment.

• Each park aims at conservation of some particular species of wildlife along with others

Important national parks in India

Name of the national park Important wildlife

Kaziranga One horned Rhino

Gir national park Indian Lion

Dachigam Hangul

Bandipur Elephant

Periyar Elephant, Tiger

Kanha Tiger

Corbett Tiger

Dudwa Tiger

Ranthambore Tiger

Sariska Tiger

Wild life sanctuaries• These are protected areas where killing, hunting,

shooting or capturing of wildlife is prohibited except under control of highest authority

Name of Sanctuary Major wild life

Ghana Bird Sanctuary 300 species of birds

Hazaribagh Sanctuary Tiger, Leopard

Sultanpur Bird Sanctuary Migratory birds

Nal Sarovar Bird Sanctuary Water birds

Abohar wildlife Sanctuary Black buck

Mudumalai wildlife Sanctuary Tiger, elephant, Leopard

Vedanthangal Bird Sanctuary Water Birds

Jaldapara Wildlife Sanctuary Rhinoceros, elephant, Tiger

Wild Ass Sanctuary Wild ass, Wolf, nilgai, chinkara

Ex situ conservation• This type of conservation is mainly done for

conservation of crop varieties, the wild relatives of crops and all the local varieties

• In this the conservation in captivity under human care

• The objective is to conserve the total genetic variability of the crop species for future crop improvement or afforestation programmes

Important gene bank/seed banks1) National Bureau of Plant Genetic Resources

(NBPGR)-Located in New Delhi

Here agricultural and horticultural crops are cryo preserved

2) National Bureau of Animal Genetic Resources(NBAGR)-Located in Haryana

Preserves semens of domesticated bovine animals

3) National Facility for Plant Tissue Culture Repository (NFPTCR)-within NBPGR

Conservation of crop plants/trees by tissue culture

Project Tiger

• Project Tiger Scheme has been under implementation since 1973 as a Centrally Sponsored Scheme of Government of India

• The main objective of Project Tiger is to ensure a viable population of tiger in India for scientific , economic , aesthetic , cultural and ecological values and to preserve for all time, areas of biological importance as a natural heritage for the benefit, education and enjoyment of the people

• Main objectives under the scheme include wildlife management, protection measures and site specific eco development to reduce the dependency of local communities on tiger reserve resources

Project Tiger• Initially, the Project started with 9 tiger reserves,

covering an area of 16,339 sq.km., with a population of 268 tigers. At present there are 27 tiger reserves covering an area of 37761 sq.km., with a population of 1498 tigers

• Project Tiger has put the tiger on an assured course of recovery from the brink of extinction, and has resurrected the floral and faunal genetic diversity in some of our unique and endangered wilderness ecosystem.

Project Elephant• Project Elephant (PE), a centrally sponsored scheme, was

launched in February 1992 to provide financial and technical support to major elephant bearing States in the country for protection of elephants, their habitats and corridors

• The Project Elephant in India also aimed to decrease the human-elephant battles and help in the welfare of domesticated elephants in India

• Aims:

1) Ecologically restoring the natural habitats and migratory routes of the elephants

2) Resolution of the increasing conflicts between man and elephants in important habitats and moderating the pressures of human and domestic stock activities in important elephant habitats

Various aims of Project Elephant4) Developing scientific and planned management measures for

conservation of elephants and controlling the population of wild Asiatic elephants, which are almost on the verge of extinction.

5) Protecting the elephants from poachers and other unnatural causes of death and illegal ivory trade is also one of the major concerns of the Elephant Project in India

6) Researching on issues related to elephants and creating public awareness and education programs for it

7) Eco-development and Veterinary care for the elephants

8) Project Elephant also aims at maintaining health care and breeding of tame elephants

Current status of Project Elephant

• The project elephant has still not led to as much increase in the number of elephants as it was expected

• Wildlife conservationists state that the progress has been real slow and people in charge of the project are themselves not very clear of the causes of decline in the number of elephants

• Project Elephant tries to ensure a free movement for the elephants and thus conserve large areas for them that are called ‘elephant reserve range’