What can excess nutrient runoff lead to in water bodies?

Excess nutrient runoff into water bodies is a significant environmental concern primarily because it leads to algal blooms and water quality degradation. This occurs when high levels of nutrients, particularly nitrogen and phosphorus, enter water systems, often as a result of agricultural practices, urban runoff, or wastewater discharges.

When these nutrients are abundant, they can stimulate the rapid growth of algae, resulting in algal blooms. These blooms can cover the surface of water bodies, blocking sunlight from reaching aquatic plants and disrupting the normal photosynthesis process. Moreover, as the algae die off, their decomposition consumes large amounts of oxygen in the water, which can lead to hypoxia—a condition where oxygen levels are so low that aquatic life, such as fish and other organisms, cannot survive.

In addition to harming fish populations and overall aquatic life, algal blooms can also produce toxins that pose health risks to humans and animals. The quality of water is further compromised as contaminants from decaying algae and the associated microbial activity lead to diminished clarity and increased levels of harmful substances.

This phenomenon highlights the critical need for effective nutrient management practices to prevent runoff, maintain healthy ecosystems, and ensure the sustainability of water resources.