2006-07-22 18:38:47 · 2 answers · asked by Kraz 2 in Environment
It means the concentration of dissolved oxygen available for fish and other aquatic life. When you discharge untreated sewage into a waterway, the bacteria that break it down use up oxygen and there is less available for other aquatic life. Water at the bottom of deep lakes and deep in the ocean is also low in available oxygen. The two sources of oxygen are contact with the atmosphere at the surface, so atmospheric oxygen dissolves in the surface water, and green algae near the surface.
2006-07-22 18:49:39 · answer #1 · answered by zee_prime 6 · 0⤊ 1⤋
Simply put it is the oxygen that is available to the fresh water environments.
I listed several websites to help with explanations. Most are glossaries and a couple are articles.
2006-07-23 03:03:29 · answer #2 · answered by fieldworking 6 · 0⤊ 0⤋