What are the factors that cause dead zones? Describe

eutrophication, in particular, as a cause.

Dead zonesare hypoxic areas (oxygen-deficient conditions). There are many areas in the world where dead zones occur namely; the Gulf of Mexico, East Coast, and Great Lakes.

Eutrophicationoccurs when there is an excess amount of phosphorus and nitrogen in waterbodies that enhances algae and plant growth.

Dead zones and eutrophication both are the consequences of anthropogenic activities. As dead zonesare hypoxic areas, marine life cannot survive. Many factors are the causes of dead zones including climatic changes, toxic water spills, and oil spills.

Eutrophication is when water bodies become enriched with minerals and nutrients, leading to algal blooms. Excessive growth of algae affects phytoplankton, seaweeds, and others as it prevents sunlight to reach them. Algal blooms are a serious threat to marine life.

Many other animals and birds dependent on marine organisms are also affected (organisms depend on fish for survival).