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Marine Ecosystems
Photic Zone
Photosynthes is limited at surface of the water:depth of about 200 feet
Sunlight penetrates a short distance om surface of the water
Marine Biologists divide the ocean into different zones depending on the depth and distance from the shore: intertidal zone, coastal zone, and open ocean zone.
Aphotic Zone
below photic zone:permanently dark
Chemosynthetic autotrophs can only live there.
Estuaries
They are affected by the rise and fall of ocean tides
wetlands formed where the river meets the sea
Primary producers: plants, algae, and both photo and chemosynthetic bacteria
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Detritus
tiny organic material that provide food for organisms at the base of the estuary's food web.
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Salt Marshes
Contain salt tolerant grasses
they are temperate zone estuaries: found in north america, from southern maine to georgia
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Mangrove Swamps
coastal wetlands
contain species of salt tolerant trees