What is the primary source of nutrient pollution in aquatic environments?

Nutrient pollution primarily stems from agricultural runoff containing fertilizers because these fertilizers are specifically designed to enhance plant growth and are rich in nitrogen and phosphorus. When it rains, these nutrients can wash off fields and into nearby waterways, leading to eutrophication, a process that causes excessive growth of algae. This algal bloom can deplete oxygen levels in the water, harming aquatic life and disrupting ecosystems. While industrial waste and residential sewage can also contribute to pollution, they typically affect water quality in different ways, such as introducing harmful chemicals or pathogens. Plastic waste presents a significant environmental issue as well, but it does not directly relate to nutrient pollution. Understanding these dynamics helps emphasize the impact agriculture has on water quality and ecosystem health.