BIOL 122 Lecture Notes - Lecture 8: Santa Barbara City College, Limnetic Zone, Littoral Zone
Document Summary
Categorized by a range of physical factors. Regions within are categorized by their proximity to sunlight. Depth of water, water flow, and salinity. Limnetic zone (open water) / photic zone. Streams support fewer species than other aquatic biomes. Shaded and nutrient poor, not much algae growth. Streams depend on allochthonus input of organic matter (dead leaves) In larger rivers, autochthonous input is much higher. As rivers move from their source they become: Matter that comes in from outside of that ecosystem. A band of terrestrial vegetation influenced by seasonal flooding. Input of organic matter produced by algae/plants within an ecosystem. Lotic systems are very sensitive to modifications of water flow. Water downstream of dam has low oxygen content. Lakes can be divided into a few different zones: Littoral: shallow area around the edge containing rooted vegetation. Limnetic (pelagic): open water beyond the littoral, prominent photosynthetic organisms are algae or phytoplankton. Profundal: only in deep lakes, no sunlight, no oxygen.
