Dissolved Oxygen is the amount of non-composed

Dissolved Oxygen is the amount of non-composed, free oxygen in water or other liquids. This is important because of its influence with the organisms also living in that same body of water. If the level is too high or low, it can affect the quality of life that the liquid gives for the organisms.
Although it can harm, Dissolved Oxygen is required for many animals including many different types of fish, invertebrates, bacteria, and plants. They also use Dissolved Oxygen for respiration, similar to land animals. The amount of Dissolved Oxygen varies, from one animal to another, for example, bottom feeders (crabs,worms, oysters) need about 1-6 mg/L, but, shallow water fish need about 4-15 mg/L.
Microbes including bacteria and fungi also need Dissolved Oxygen to survive. The microbes use Dissolved Oxygen to decompose organic material. Microbial decomposition is what that process is called.There is also a dying excess of the decaying organic material, caused by dying algae and other organisms, in a body of water with an infrequent or almost no turnover at all, and the Dissolved Oxygen levels will decrease quicker.
The entrance for Dissolved Oxygen in water is through air or as a plant byproduct. From the air, the oxygen slowly diffuses on the water’s surface from the surrounding atmosphere, or, it could be mixed in at a fast pace through aeration, manmade or natural. The process of ae