BIOL 1108 Lecture Notes - Lecture 47: Photic Zone, Hydrogen Sulfide, Deep Sea
Document Summary
The part of the ocean that is neither close to shore nor close to the seafloor - forms the bulk of the oceanic system. Organisms live within the water column, as plankton. In the upper 200 meters or so of the pelagic realm, sunlight permits photosynthesis, this is the photic zone. Photic zone has diverse algae and cyanobacteria as primary producers. In deeper waters, life is sustained by the rain of organic particles from surface waters. Recent research shows that in the upper water column, heterotrophic protists may actually be more abundant and diverse. Biologically driven cycles of carbon and other essential elements shape ecology and reflect evolution. Deep sea waters are cold and dark, but they are not sterile. Sinking detritus supports sparse populations of animal consumers, as well as bacteria and archaeons that feed on organic particles. Deep sea biomes exhibit high species diversity, as high as those of shallow marine communities.
