This is the first step in the chain of reactions that can lead to hypoxia. The amount of pollutants generated and the rate at which they reach rivers, estuaries and coastal waters are increased by human activities such as the destruction of wetlands, grasslands, and forests in favor of urban or suburban landscapes and many agricultural practices. Through the Tampa Bay National Estuary Program and other efforts, the community agreed to meet a reduction goal of 17 tons of nitrogen per year for at least five years. This goal will allow for economic growth in the Tampa region without causing additional nutrient enrichment problems. It also tends to stay that way for longer periods of time.
Hypoxia develops when a series of conditions occur together.
The diagram below explains how they interact. These algae have to sink or otherwise end up on the bottom. On the bottom, the algae or fecal pellets decompose. This process of decomposition consumes oxygen. The largest hypoxic zone in the United States forms every spring and summer in the Gulf of Mexico just west of the mouth of the Mississippi River.