Eutrophication is described as the natural aging process of a water body, when chemical nutrients, typically compounds containing nitrogen and phosphorus start to overwhelm it. This happens naturally but is accelerated by manmade activities and events. As nutrients start to take over, the water body starts to favor plant life over animal life.
Plant life can vary, but there are types of nuisance algae that are very common in eutrophic water bodies. Not all algae are bad. Diatoms are a very beneficial form of algae and have the benefit of keeping other nuisance forms of algae in check. Generally there are 3 types of nuisance algae that are most common:
As nutrient levels increase, plant life will increase as well. If an abundance of algae grows, the water will be shaded and weeds, which need sunlight, will be unable to grow. If the problem is excessive weed growth, the weeds will take up most of the nutrients so the algae will be unable to grow.
Algae blooms can be an eyesore, make recreation and fishing difficult, and cause an odor. Blue-green algae blooms can also be toxic or harmful. When bodies of water experience rapid algal blooms, the amount of dissolved oxygen in the water can vary greatly–dissolved oxygen can increase significantly during the day but can also drop dangerously low after dark because of respiring algae. In many circumstances, oxygen levels decline dangerously causing fish and other aquatic life to suffer. For all these reasons and more, algae control may become necessary.