Phytoplankton, Macroalgae, Phytoplankton, Macroalgae, and Eutrophication Problems and Eutrophication Problems

in the Baysin the Bays

Subproject # 2—Phytoplankton and Macroalgal Subproject # 2—Phytoplankton and Macroalgal Studies in MD Coastal BaysStudies in MD Coastal Bays

Dr. Madhumi MitraDr. Madhumi MitraAssociate Professor of Biological and Environmental Associate Professor of Biological and Environmental

SciencesSciencesCoordinator of Biology and Chemistry EducationCoordinator of Biology and Chemistry Education

7/18/127/18/12E-mail: mmitra@umes.eduE-mail: mmitra@umes.edu

ALGAEALGAEStudy of Algae--Study of Algae--

PhycologyPhycology How are algae similar to higher plants?How are algae similar to higher plants?

How are algae different from higher How are algae different from higher plants?plants?

FOSSIL HISTORY OF FOSSIL HISTORY OF ALGAEALGAE

3.5 billion yrs ago3.5 billion yrs ago Cyanobacteria—first algaeCyanobacteria—first algae Prokaryotes—lack membrane bound Prokaryotes—lack membrane bound

organellesorganelles Later eukaryotes evolved—Later eukaryotes evolved—

mitochondria, chloroplasts, and mitochondria, chloroplasts, and chromosomes containing DNA.chromosomes containing DNA.

SimilaritiesSimilarities

Presence of cell wall—mostly Presence of cell wall—mostly cellulosic.cellulosic.

Autotrophs/Primary producers—Autotrophs/Primary producers—carry out photosynthesiscarry out photosynthesis

Presence of chlorophyll aPresence of chlorophyll a

DifferencesDifferences

Algae lack the roots, stems, leaves, and other Algae lack the roots, stems, leaves, and other structures typical of true plants. structures typical of true plants.

Algae do not have vascular tissues—non Algae do not have vascular tissues—non vascular plantsvascular plants

Algae do not form embryos within protective Algae do not form embryos within protective coverings.coverings.

Variations in pigments.Variations in pigments. Variations in cell structure—unicellular, colonial Variations in cell structure—unicellular, colonial

and multicellular forms.and multicellular forms.

PROKARYOTIC VS PROKARYOTIC VS EUKARYOTIC ALGAEEUKARYOTIC ALGAE

ProkaryotesProkaryotes---No nuclear region and ---No nuclear region and

complex organelles—complex organelles—chloroplasts, mitochondria, chloroplasts, mitochondria, golgi bodies, and golgi bodies, and endoplasmic reticula.endoplasmic reticula.

-- -- Cyanobacteria. Chlorophylls Cyanobacteria. Chlorophylls are on internal membranes of are on internal membranes of flattened vesicles called flattened vesicles called thylakoids-contain thylakoids-contain photosynthetic pigments. photosynthetic pigments. Phycobiliproteins occur in Phycobiliproteins occur in granular structures called granular structures called phycobilisomes.phycobilisomes.

Prokaryote algal cellProkaryote algal cell

Source: http://www.botany.hawaii.edu/faculty/webb/BOT311/Cyanobacteria/Cyanobacteria.htm

Prokaryotic and Prokaryotic and Eukaryotic AlgaeEukaryotic Algae

EukaryotesEukaryotes

---Distinct chloroplast, ---Distinct chloroplast, nuclear region and nuclear region and complex organelles.complex organelles.

--- Thylakoids are --- Thylakoids are grouped into grana grouped into grana

granum with aStack of thylakoids

pyrenoid

DIVERSITY IN ALGAEDIVERSITY IN ALGAE

BODY OF AN BODY OF AN ALGA=THALLUSALGA=THALLUS

DIVERSITY IN DIVERSITY IN MORPHOLOGYMORPHOLOGY

----MICROSCOPIC----MICROSCOPIC

Unicellular, Colonial, Unicellular, Colonial, and Filamentous and Filamentous forms.forms.

Source: http://images.google.com/images

CELLULAR CELLULAR ORGANIZATIONORGANIZATION

Flagella=organs of Flagella=organs of locomotion.locomotion.

Chloroplast=site of Chloroplast=site of photosynthesis. Thylakoids photosynthesis. Thylakoids are present in the chloroplast. are present in the chloroplast. The pigments are present in The pigments are present in the thylakoids.the thylakoids.

Pyrenoid-structure associated Pyrenoid-structure associated with chloroplast. Contains with chloroplast. Contains RUBP Carboxylase, proteins, RUBP Carboxylase, proteins, and carbohydrates.and carbohydrates.

Eye-spot=part of chloroplast. Eye-spot=part of chloroplast. Directs the cell towards light.Directs the cell towards light.

Source: A Biology of the AlgaeBy Philip Sze, third edition, WCB MCGraw-Hill

Variations in the pigment Variations in the pigment constitutionconstitution

Chlorophylls (green)Chlorophylls (green) Carotenoids (brown, yellow or red)Carotenoids (brown, yellow or red) Phycobilins (red pigment-phycoerythrinPhycobilins (red pigment-phycoerythrin

blue pigment –blue pigment –phycocyanin)phycocyanin)

ECOLOGICAL DIVERSITYECOLOGICAL DIVERSITY

LAND---WATERLAND---WATER FRESH WATER---MARINE HABITATSFRESH WATER---MARINE HABITATS FLOATING (PLANKTONIC)—BENTHIC FLOATING (PLANKTONIC)—BENTHIC

(BOTTOM DWELLERS)(BOTTOM DWELLERS) EPIPHYTESEPIPHYTES

PHYTOPLANKTONPHYTOPLANKTON

AutotrophicAutotrophic Free-floatersFree-floaters MicroscopicMicroscopic Mostly unicellular although some are Mostly unicellular although some are

colonial and filamentouscolonial and filamentous

CLASSIFICATIONCLASSIFICATION

PhytoplanktonPhytoplankton

----Picoplankton-0.2 to 2----Picoplankton-0.2 to 2µmµm

----Nanoplankton-2.0 to 20----Nanoplankton-2.0 to 20µmµm

----Microplankton-20 to 200----Microplankton-20 to 200µmµm

Picoplankton are important contributors to primary Picoplankton are important contributors to primary productivity of plankton. Biomass in surface waters range productivity of plankton. Biomass in surface waters range from 40-50Pg C/year (P=peta, and 1 Pg is equivalent to from 40-50Pg C/year (P=peta, and 1 Pg is equivalent to 10 10 1515 g). g).

CYANOPHYTA, CHLOROPHYTA, PYRRHOPHYTA, CYANOPHYTA, CHLOROPHYTA, PYRRHOPHYTA, CRYPTOPHYTA, CHRYSOPHYTA, CRYPTOPHYTA, CHRYSOPHYTA, BACILLARIOPHYCEAEBACILLARIOPHYCEAE

LIGHTLIGHT

Irradiance is inversely proportional to water Irradiance is inversely proportional to water depth. depth.

COMPENSATION DEPTHCOMPENSATION DEPTH --- Different --- Different species have different compensation species have different compensation depths. Rate of photosynthesis equals rate depths. Rate of photosynthesis equals rate of respiration. No production of biomass of respiration. No production of biomass takes place. Cells below the compensation takes place. Cells below the compensation depth are unable to grow and deplete their depth are unable to grow and deplete their resources. resources.

NUTRIENTSNUTRIENTS

Nutrient concentrations vary in Nutrient concentrations vary in different bodies of water. different bodies of water.

EUTROPHYEUTROPHY-Nutrient enrichment -Nutrient enrichment OLIGOTROPHYOLIGOTROPHY-Low nutrient -Low nutrient

level level Macroelements-C, H, O, S, K, Ca, Mg, P, Macroelements-C, H, O, S, K, Ca, Mg, P,

and N. and N. Microelements-cofactors-Fe, Mn, Cu, Microelements-cofactors-Fe, Mn, Cu,

Zn, Mb. Si is required by all diatoms.Zn, Mb. Si is required by all diatoms.

Limiting Nutrients for Limiting Nutrients for GrowthGrowth

Nitrogen---NNitrogen---N22, NH, NH44++, NO, NO33

--, NO, NO22--, and urea., and urea.

Phosphorus---Inorganic phosphate can Phosphorus---Inorganic phosphate can occur in a number of forms occur in a number of forms (HPO(HPO44

2-2-,PO,PO443-3-;and H;and H22POPO44

--

Sulfur—SOSulfur—SO442-2-,H,H22SS

NITROGEN FIXATION IN NITROGEN FIXATION IN CYANOBACTERIACYANOBACTERIA

Reference:Biology of AlgaeBy Sze

NITROGENNITROGEN

Nitrate is the primary source of nitrogen Nitrate is the primary source of nitrogen utilized by algaeutilized by algae

Nitrate----(nitrate reductase)Nitrate----(nitrate reductase)Nitrite---Nitrite---(nitrite reductase)--(nitrite reductase)--Ammonium.Ammonium.

Ammonium is utilized in cell metabolism.Ammonium is utilized in cell metabolism.

PHOSPHORUSPHOSPHORUS

Phosphate in different formsPhosphate in different forms Organic phosphates---broken down by Organic phosphates---broken down by

phosphatases in the membrane of algae. phosphatases in the membrane of algae.

FLOATING AND SINKINGFLOATING AND SINKING

Photosynthesis goes upAccumulation of polysaccharides

Gas vesicles collapse

Buoyancy decreases Cells sinkPhotosynthesis

decreases

Increased vacuolation

Buoyancy increases Cells rise

DIVERSITY IN ALGAEDIVERSITY IN ALGAE

Photos are by Dr. Mitra’s Research Group. These pictures are not to be used for any purpose without Dr. Mitra’s approval.

MACROALGAE

WHAT ARE SEAWEEDS?WHAT ARE SEAWEEDS?

Macroalgae found in estuarine and marine Macroalgae found in estuarine and marine environments.environments.

Non-vascular, multicellular, and photosynthetic Non-vascular, multicellular, and photosynthetic plants.plants.

ChlorophytaChlorophyta, , RhodophytaRhodophyta, and , and PhaeophyceaePhaeophyceae ---wall chemistry, chloroplast ---wall chemistry, chloroplast structures and pigmentation, arrangement of structures and pigmentation, arrangement of flagella in motile cells, and life cycles.flagella in motile cells, and life cycles.

Found in polar, tropical, and temperate waters Found in polar, tropical, and temperate waters around the globe.around the globe.

WHY DO WE CARE ABOUT WHY DO WE CARE ABOUT SEAWEEDS?SEAWEEDS?

Primary producers-important Primary producers-important role in the marine trophic role in the marine trophic structurestructure

Calcareous seaweeds –major Calcareous seaweeds –major contributors to the structure of contributors to the structure of coral reefs (they can make up coral reefs (they can make up 30% of the reef). 30% of the reef). PorolithonPorolithon and and LithophyllumLithophyllum

Mangroves and seagrass Mangroves and seagrass beds—seaweeds can provide beds—seaweeds can provide a rich source of food for a rich source of food for detritus feeders such as detritus feeders such as fiddler crabs. These fiddler crabs. These seaweeds can also be seaweeds can also be important food sources for important food sources for amphipods and isopods.amphipods and isopods. Gracilaria-epiphyte of Zostera marina

Photo: Dr. Mitra

WHY DO WE CARE ABOUT WHY DO WE CARE ABOUT SEAWEEDS?SEAWEEDS?

Seaweeds that are edible are called Seaweeds that are edible are called “seavegetables”“seavegetables”

Health-promoting/medicinal properties Health-promoting/medicinal properties (treatment of cancers, heart diseases, (treatment of cancers, heart diseases, rheumatism, blood sugar, and flu)rheumatism, blood sugar, and flu)

Effective fertilizers, soil conditioners, and are a Effective fertilizers, soil conditioners, and are a source of livestock feedsource of livestock feed

Used in wide range of products from ice cream Used in wide range of products from ice cream to fabric dyes.to fabric dyes.

WHY DO WE CARE ABOUT WHY DO WE CARE ABOUT SEAWEEDS?SEAWEEDS?

Used as “biological scrubbers”—Used as “biological scrubbers”—UlvaUlva Gels from seaweeds—Agar is derived from red Gels from seaweeds—Agar is derived from red

seaweeds (seaweeds (GelidiumGelidium, , GracilariaGracilaria, , Hypnea, Hypnea, and and PterocladiaPterocladia). It is used in microbiological ). It is used in microbiological growth medium and food industry. growth medium and food industry. Carrageenans are obtained from Carrageenans are obtained from ChondrusChondrus and and GigartinaGigartina. Alginates are found in the cell . Alginates are found in the cell walls of many brown seaweeds. Primary walls of many brown seaweeds. Primary sources are sources are MacrocystisMacrocystis, , AscophyllumAscophyllum, and , and LaminariaLaminaria..

ECOLOGICAL PROBLEMECOLOGICAL PROBLEM

Nutrient and sediment loads

Eutrophication

Development of opportunistic and tolerant micro and macroalgae

Environmental conditions become unfavorable and algae die anddecompose

Large biomass

Recycling of nutrientsand pollutants in the ecosystem

Increasein herbivore population

toxicity rises

Water quality deteriorates

Anoxia

Death oforganisms

Photosynthesis declines

Courtesy: Dr. Mitra

Water acidification

IMPACTS OF SEAWEED IMPACTS OF SEAWEED BLOOMSBLOOMS

Benthic macroalgae have a low C/N Benthic macroalgae have a low C/N content (rich in nitrogen and low in content (rich in nitrogen and low in structural carbohydrates). Their structural carbohydrates). Their decomposition can stimulate bacterial decomposition can stimulate bacterial activity. This can result in sediment activity. This can result in sediment resuspension and high turbidity.resuspension and high turbidity.

IMPACTS OF SEAWEED IMPACTS OF SEAWEED BLOOMSBLOOMS

Light availability—incident irradiation was attenuated. Light availability—incident irradiation was attenuated. PRIMARY EFFECTPRIMARY EFFECT

SECONDARY EFFECTSSECONDARY EFFECTS ---- Increase in ammonium concentrations within ---- Increase in ammonium concentrations within

macroalgal mats. These levels may be toxic to macroalgal mats. These levels may be toxic to eelgrass (van Katwijk et al. 1997).eelgrass (van Katwijk et al. 1997).

----- Increase in sediment sulfide concentrations resulting ----- Increase in sediment sulfide concentrations resulting from decaying macroalgal layer. Sediment sulfide can from decaying macroalgal layer. Sediment sulfide can reduce photosynthesis. reduce photosynthesis.

----Anoxia. High sulfide and low oxygen concentrations ----Anoxia. High sulfide and low oxygen concentrations can reduce growth and production of seagrasses by can reduce growth and production of seagrasses by decreasing nutrient uptake and plant energy status.decreasing nutrient uptake and plant energy status.

TYPES OF SEAWEEDSTYPES OF SEAWEEDS(MORPHOLOGICAL TYPES)(MORPHOLOGICAL TYPES)

Sheet likeSheet like Filamentous groupFilamentous group Coarsely branched groupCoarsely branched group Thick-leathery groupThick-leathery group Jointed calcareous groupJointed calcareous group Crustose groupCrustose group

SHEET GROUPSHEET GROUP

Thin, tubular or Thin, tubular or sheetlike.sheetlike.

Soft Soft Photosynthetic Photosynthetic

activity-highactivity-high Toughness-lowToughness-low Examples: Examples: Ulva, Ulva,

Enteromorpha, Enteromorpha, PorphyraPorphyra..

Photos: Dr. Mitra’s Lab

Ulva lactuca

Enteromorpha intestinalis

FILAMENTOUS GROUPFILAMENTOUS GROUP

Delicate branchesDelicate branches Texture-SoftTexture-Soft Photosynthetic Photosynthetic

activity-moderateactivity-moderate Toughness-lowToughness-low Chaetomorpha, Chaetomorpha,

Cladophora, Cladophora, CeramiumCeramium

Photo: Dr. Mitra’s Lab

Ceramium rubrum

COARSELY BRANCHED COARSELY BRANCHED GROUPGROUP

Coarsely branchedCoarsely branched Pseudoparenchymatous Pseudoparenchymatous

to parenchymatousto parenchymatous Texture—fleshy to wiryTexture—fleshy to wiry Toughness-lowToughness-low Gigartina, Chondrus, Gigartina, Chondrus,

AgardhiellaAgardhiella

Agardhiella tenera

Photos: Dr. Mitra’s lab

Gracilaria tikvahiae

THICK LEATHERY GROUPTHICK LEATHERY GROUP

Thick blades and Thick blades and branchesbranches

Texture-leatheryTexture-leathery Photosynthetic rate –Photosynthetic rate –

lowlow Toughness-highToughness-high Fucus, Laminaria, Fucus, Laminaria,

Sargassum, PadinaSargassum, PadinaPhoto: Dr. Mitra’s LabPhoto: Dr. Mitra’s Lab

Fucus vesiculosus

JOINTED-CALCAREOUS TYPEJOINTED-CALCAREOUS TYPE

Calcareous, uprightCalcareous, upright Calcified segments, Calcified segments,

flexible jointsflexible joints Texture-stonyTexture-stony Photosynthetic rate-Photosynthetic rate-

very lowvery low Toughness-very highToughness-very high Corallina, HalimedaCorallina, Halimeda

Reference: http://seaweed.ucg.ie/descriptions/Coroff.html

Corallina officinalis

CRUSTOSE GROUPCRUSTOSE GROUP

EncrustingEncrusting Calcified, some Calcified, some

uncalcifieduncalcified Texture-stony, toughTexture-stony, tough Photosynthetic Photosynthetic

activity-lowactivity-low Toughness-very highToughness-very high Encrusting corallines, Encrusting corallines,

Ralfsia,HildenbrandiaRalfsia,Hildenbrandia

Hildenbrandia

Reference: http://www.guiamarina.com/chile/02%20plants/Rhodophyceae/Hildenbrandia%20sp..htm

BENTHIC MARINE ALGAE-BENTHIC MARINE ALGAE-MORPHOLOGICAL TYPESMORPHOLOGICAL TYPES

Which forms have the least resistance to Which forms have the least resistance to herbivores?herbivores?

Which forms have the highest resistance to Which forms have the highest resistance to herbivores?herbivores?

Which ones are late successional forms?Which ones are late successional forms?1.1. Sheet likeSheet like2.2. Filamentous groupFilamentous group3.3. Coarsely branched groupCoarsely branched group4.4. Thick-leathery groupThick-leathery group5.5. Jointed calcareous groupJointed calcareous group6.6. Crustose groupCrustose group

NUISANCE MACROALGAL SPECIES OF THE COASTAL BAYSNUISANCE MACROALGAL SPECIES OF THE COASTAL BAYS

Photos: Dr. Mitra’s Lab

Assignment/Group Assignment/Group ActivityActivity

How will you incorporate Algae in your How will you incorporate Algae in your curriculum?curriculum?

How will you incorporate Eutrophication How will you incorporate Eutrophication in your curriculum?in your curriculum?