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Aquatic Biomes. A BIOME is a major ecosystem spread over a wide geographic area, and characterized by certain types of flora and fauna. . Major Aquatic Biomes - These occupy most of the biosphere.
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Aquatic Biomes A BIOME is a major ecosystem spread over a wide geographic area, and characterized by certain types of flora and fauna.
Major Aquatic Biomes - These occupy most of the biosphere Life originated in the oceans, and stayed there for nearly 3 billion years. The oceans are the most influential of all terrestrial features affecting climate and biomes.
Aquatic biomes may be • marine (average salinity 3%) • freshwater (average salinity 1% or less) • brackish (mixture of salt/fresh)
Freshwater biomes may be: • Lakes/ponds • River systems
Freshwater or Brackish systems may be: • Estuaries • Marshes and wetlands
Marine • intertidal regions • coral reefs • oceanic pelagic zones • abyssal zones
Stratification of Aquatic Biomes • Light is absorbed by water and by living aquatic organisms... • · photic zone - light sufficient for photosynthesis • · aphotic zone - light insufficient for photosynthesis
Zonation in freshwater biomes • littoral zone - inshore, shallow, high light levels • limnetic zone – center of lake, high light levels, upper regions of water column (pelagic zone for the ocean!) • profundal zone – aphotic • benthic zone – bottom substrate; often rich in detritus
Classification of Freshwater Biomes by Productivity • oligotrophic- deep, nutrient poor, water very clear • eutrophic- shallower, nutrient rich, murky with phytoplankton • mesotrophic- in between the above two classifications