1. YASHWANTKUMAR.R.S.

2.  The organisms inhabiting the pelagic zone are grouped
into two broad categories-plankton & nekton.
 The word plankton was first of coined by Henson
,which means that which drifts.
 Plankton further divided into phytoplankton &
zooplankton.
 Most phytoplankton are too small to be individually
seen with the unaided eye.
 When they present in high enough numbers ,they may
appear as green discoloration of the water due to the
presence of chlorophyll within their cells.
INTRODUCTION

3. 
 Phytoplankton include wide variety of
photosynthetic organism like
1) Diatoms
2) Dinoflagellates
3) Cryptomonads
4) Green algae
5) Blue green algae
 Out of these diatoms & dinoflagellates are
predominate.
TYPES OF
PHYTOPLANKTON

4. 
 The diatoms are enclosed within a box made up of
two parts or valves fitting one over another.
 The box is made up of silicon dioxide & is
ornamented with species specific designs pits &
perforations.
 They are dominant in temperate & colder regions.
 They may occur singly or may occur in chains.
DIATOMS

5. 
DIATOMS THALASSIOSIRA

6. 
 The second major group of phytoplankton is
recognizable by possesssing two flagella.
 They use flagella to move themselves through the
water.
 They lack the external skeleton of silicon but are
often armored with plates of the carbohydrates
cellulose.
 They are solitary , single small organisms.
DINOFLAGELLATES

7. 
 The microscopic phytoplankton float on or near the
surface of water.
 As they are autotrophic components of the plankton
community they are responsible for much of the
oxygen present in earth’s atmosphere.
 The population of phytoplankton in any aquatic system
is biological wealth of water for fishes & constitutes a
vital link in the food chain.
 Phtyoplankton have definite role in proper growth &
maintenance of a water body.
ECOLOGICAL
BALANCE

8. 
 Phytoplankton is a key food item in both Aquaculture &
mariculture .And it is utilized as food for animals being
farmed.
 In mariculture , the phytoplankton is naturally occuring
& is introduced into enclosures with the normal
circulation of sea water.
 In aquaculture, phytoplankton must be obtained &
introduced directly.
 Phytoplankton is also used to feed many varieties of
aquacultured molluscs, including pearl oysters.
BENEFITS

9. 
 As the marine phytoplankton have declined
substantially in the world’s oceans over the past
century.
 Phytoplankton in surface waters have decreased by
about 40% since 1950 alone, at a rate of 1% per year
due to ocean warming.
 Due to emission of carbon dioxide from humans it
causes increases in disturbances in marine food web
& due to this there is a percentage decline in the fish
species which feed on phytoplankton
HUMAN IMPACTS

10. 

11. 
 As marine phytoplankton is declining substantially
in the world’s ocean.
 There must be decrease in not only in air borne
fraction of pollutions but also in other type of
pollutions from humans.
 Due to this there will be a enrichment in marine
ecology.
CONCLUSION

12. 
 Buschbaum, Ralph and Milne, Lorus J. 1960. The
Lower Animals, Doubleday and Co. New York.
 Silverberg, Robert. 1972. The World Beneath the
Ocean Wave. Weybright and Talley, New York.
REFERENCES

13. THANK YOU