Human activity has increased eutrophication in water bodies around the world.
Eutrophication refers to an increase in nutrients in a body of water. Although eutrophication is a natural process, when it accelerates it is a cause for concern. Many human activities have led to widespread eutrophication in rivers, streams, lakes, and oceans throughout the world. If left unchecked, eutrophication becomes a problem that seriously affects water quality and biodiversity. Eutrophication was first recognized as a problem in the mid-20th century, and is studied extensively by many biologists in an attempt to prevent further eutrophication of vital water bodies around the world.
As the fertilizers enter the water supply, they stimulate an explosion of plants and algae, an event sometimes called an algal bloom.
In the sense of a natural process, eutrophication is part of the aging of water bodies. When a body of water initially forms, it tends to be poor in nutrients. As streams feed the body of water, they carry nutrients that encourage plant life, allowing other species to grow as well. A layer of sediment grows slowly and gradually the body of water will eventually become a swamp or bog as the sediment displaces the water and the species in the area change.
However, eutrophication can be rapidly accelerated by human activities, in which case it is known as “nutrient pollution”. Fertilizer and manure runoff from farms is one of the leading causes of eutrophication worldwide. As these nutrients enter the water supply, they stimulate an explosion of plants and algae, an event sometimes called an algal bloom. Plant life drastically reduces the amount of oxygen available in the water, eventually suffocating animal species and creating a so-called “dead zone.”
Oceanic dead zones are a big problem, as many of them arose in areas where one of them produced abundant marine life. The Gulf of Mexico, for example, has an infamous dead zone that is larger than the state of New Jersey. Lakes and rivers that are experiencing eutrophication can be easily identified as they often turn bright green or red as a result of algae blooms in their waters. These shocking colors are signs of serious health problems and of great concern to scientists.
Since eutrophication is undesirable, many nations have worked to prevent it. Farms, for example, are expected to closely monitor their fertilizers and manure, and environmental agencies can fine these facilities for runoff above acceptable levels. Many countries are also trying to remove nutrient pollution from their waters and may use other measures to create eutrophication buffer zones, preventing the problem from spreading.