Question

What are human activities that cause dead zones??

Answer 1

Dead zones: Low-oxygen containing (hypoxic) areas in the oceans and large water bodies. There are approximately 405 dead zones identified till now in the world. The formation of dead zones in the ocean is a natural phenomenon.

Dead zones are also caused by oxygen depletion due to human activities that increase nutrient pollution. The major cause of dead zone formation is eutrophication. Eutrophication is caused by dumping nutrient-rich sewage, waste materials, agricultural and industrial effluents into the ocean. this leads to the excessive growth of organisms in that area leading to increased biological oxygen demand.