Dissolved Oxygen

Dissolved oxygen is how fish, caddisflies, and hellegrammites breath. It is oxygen that the water grabs whileit is going over rocks. These areas with the rocks are called riffle areas. A way that oxygen can get used up is when fertilizers slide into the water with the soil by erosion. The algae feeds on the nitrogen in the fertilizer. Then there will be an algal bloom that will block the sun's rays. The algal bloom also eats up all the dissolved oxygen. In this picture, the algal bloom almost looks like sand. With the algae blocking the sun's rays and taking up all the dissolved oxygen, it doesn't leave a very good living environment for other living things.