Overabundance of nutrients in a fresh water source. Creates algal blooms.

Answer 1

This is known as eutrophication, which occurs when there is an excessive amount of nutrients such as nitrogen and phosphorus in a body of water. These nutrients stimulate the growth of algae and cyanobacteria, leading to algal blooms. These blooms can have negative impacts on aquatic ecosystems such as oxygen depletion, fish kills, and the release of toxins that can harm human and animal health. Eutrophication is often caused by agricultural runoff, sewage discharge, and fertilizer use, and can be exacerbated by climate change and urban development. Efforts to reduce nutrient pollution and improve water quality are crucial in preventing and mitigating eutrophication.