Question

What causes eutrophication and how does this occur? (Site 1)

Answer 1

Eutrophication is caused by an excess of nutrients, particularly nitrogen and phosphorus, in a water body. These nutrients can come from various sources, such as agricultural runoff, sewage discharge, and industrial effluent. When these nutrients enter the water, they fuel the growth of algae and aquatic plants, which use the nutrients for photosynthesis. As the algae and plants grow, they can create dense mats on the water surface, cutting off light and oxygen to the lower layers of the water. When the plants and algae eventually die, they sink to the bottom and decompose, using up the available oxygen in the water. This can lead to hypoxia, or low oxygen levels, which can result in the death of fish and other aquatic organisms. Additionally, some types of algae, such as blue-green algae, can release toxins that are harmful to animals and humans. Overall, eutrophication can have devastating effects on aquatic ecosystems, and it is a growing concern in many parts of the world.