Phytoplankton
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Phytopla.jpg
Phytoplankton refers to the algal or plant-like component of the plankton that drifts in the water column. The name comes from the Greek terms, phyton or "plant" and <math>\pi\lambda\alpha\gamma\kappa\tau o\nu<math>, meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye. However, when present in high numbers, their presence may appear as discoloration of the water.
Phytoplankton, like other plants, obtain energy through a process called photosynthesis, and so must live in the well-lit surface layer (termed the euphotic zone) of an ocean, sea, or lake. Through photosynthesis, phytoplankton produce approximately 98% of atmospheric oxygen. Their cumulative energy fixation in carbon compounds (primary production) is the basis for the vast majority of oceanic (see chemosynthesis) and some freshwater food chains. One of the most remarkable and direct food-chains in the ocean is that of phytoplankton fed on by krill (a type of shrimp), fed on by baleen whales.
The most important groups of phytoplankton are the diatoms and dinoflagellates, but many other groups of algae also occur. One class (coccolithophores) may also release significant amounts of dimethyl sulfide (DMS) into the atmosphere. The DMS is converted to sulfate and these sulfate molecules act as cloud condensation nuclei, increasing cloud cover.
See also
Phytoplankton_bloom_in_the_Baltic_Sea_(July_3,_2001).jpg
External link
- DMS and Climate (http://saga.pmel.noaa.gov/review/dms_climate.html)da:Planteplankton
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