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PHYTOPLANKTON. Pelagic environment is the largest marine ecosystem. More food, oxygen and biota (life) are here than anywhere else. Spirogyra. The dominant organism in the neritic zone and oceanic zone is plankton. Plankton are organisms that can not make a forward motion against a current.
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PHYTOPLANKTON Pelagic environment is the largest marine ecosystem. More food, oxygen and biota (life) are here than anywhere else. Spirogyra The dominant organism in the neritic zone and oceanic zone is plankton. Plankton are organisms that can not make a forward motion against a current.
Phytoplankton are found in 3 Kingdoms and 5 Phyla that ends with the suffix “phyta”. Commercially, algae are used as emulsifiers to give a smooth texture to puddings, toothpaste, ice cream, and shoe polish.
There are 2 types of plankton: phytoplankton & zooplankton. Volvox Phytoplankton are photosynthetic autotrophs, who begin all marine food webs. They produce 50-90% of all atmospheric oxygen, and are critical biomass.
They are adapted to a floating life style because of their: 1. small size - diffusion is quick, frictional drag from large surface area to low volume ratio helps slow sinking 2. structure - disks shaped or chains aid in floating 3. low density - light ions and lipid by-products of photosynthesis reduce density and aid floating They are grouped by color. Different pigments allow them to take advantage of different light penetration at various depths.
A “bloom” is an increase in population density of phytoplankton associated with high nutrient levels. It can be the result of upwelling or excessive nutrients. Upwelling is caused by winds and other atmospheric conditions that move surface water away from shore, pulling nutrient rich bottom water to the surface.
Diatoms are dominants in cool water. Variety of Diatoms Blooms are good for the food chain, fishing and trigger whale migrations. NOAA
The dominant phytoplankton in warm water are dinoflagellates Possess flagella (tail-like structure, common to all flagellates) Dinoflagellate moving Dinoflagellate moving - take 2 They cause a condition called Red Tide.
Blooms of some dinoflagellate plankton, may be harmful. When storms follow hot, dry weather, dormant cysts of toxic phytoplankton may be released. As these toxic blooms enter the food chain, they give off chemical neurotoxins that paralyze the predator’s nerves controlling breathing and heart rate. Human consumption of these organisms result in paralytic shellfish poisoning and hepatitis due to biomagnification.
A change in winds direction blows surface water toward the land and prevents upwelling. Water is depleted of nutrients and fishing is poor. Red Tide is a result of an onshore wind pattern, Peruvian fishermen named El Nino. The name refers to the Christ Child, because the condition was first observed during the warm, Christmas months of the southern hemisphere. Wind Land No upwelling Ocean