Researchers at the University of Nebraska, the University of Iowa, and Coe College have been studying a major nitrogen pulse in the Cedar and Iowa River watersheds. This release of excess nitrogen, mostly from agricultural runoff, may be partially responsible for the increased expansion of the Gulf of Mexico’s dead zone, which has doubled in size since last year.
The pulse could be bad news for aquatic life in the Gulf. Nitrogen-rich water is ideal for the growth of algae, which reduces oxygen levels in the water as it decomposes. Plants and animals that depend on oxygen are left to suffocate and die.
Nitrogen-rich water can be dangerous for humans as well; a recent study of women in Iowa and Texas linked nitrate levels in drinking water consumed during pregnancy with occurrences of birth defects in children.
Last year, as part of the Iowa Nutrient Reduction Strategy, Iowa farmers were asked to participate in the reduction of nutrient load in Iowa waters. There have been concerns that the voluntary nature of the plan may not yield significant cuts in the quantities of nitrogen and phosphorus reaching the Gulf.
To learn more about agricultural runoff and its effects on the environment, click here.