The long term result of this erosion can alter the topography of these shallow water areas enough that they are unable to support shallow water organisms. Shade Cools water, provides method of protection from predators, affects aquatic plant productivity. Sunlight Necessary for photosynthesis, aquatic plant productivity, phytoplankton in oceans, affects water temperature and air temperature. Cools surface of oceans, creates mixing of oxygen and nutrients in larger bodies of water such as lakes resulting in thermoclines or layering of water by temperature gradients. One of the most important of these is the ability of water to hold certain chemicals.
Cold water holds more oxygen, for example, than hot water.
Turbidity High turbidity results from suspended materials such as sediments, chemicals or dense clouds of microscopic plants and animals called plankton. All of these increase turbidity and reduce the amount of light that penetrates the water. High levels can harm plants and animals by decreasing the amount of light available for the growth of algae and seagrasses. High levels can also clog the gills of fish, shellfish and others, killing them by suffocation. Infectious Agents are pathogenic organisms such as bacteria, viruses, protozoa, parasitic worms, typhoid, cholera, and dysentery that enter water from sewage and pasture runoff or come from natural sources.