Integrated Crop Management is published by the Department of Entomology , Iowa State University , Ames, Iowa. It is normal for P to exist in Iowa's aquatic systems. But the levels that now exist are some of the highest in the world. It is not normal or healthy, and contributes to a condition called eutrophication, the overfertilization of aquatic systems that generates unnaturally vigorous algal growth, also known as algal blooms.
Algal blooms are frequently the result of nutrient pollution resulting from human activities.
P losses from Iowa's soil were very slight. When aquatic systems become eutrophic, their natural systems cease functioning efficiently and begin to break down. Healthy aquatic systems are not only indicators of healthy landscapes but also are economically important. One of the negative impacts of eutrophication is the unpleasant smell of decomposing algae, impairing recreational use of water. Few agricultural lands generate as much.