Dead zone

Definition

A dead zone is an area in a body of water with extremely low oxygen levels, making it uninhabitable for most marine life. Often caused by nutrient pollution leading to excessive algae growth and subsequent decomposition that depletes oxygen.

5 Must Know Facts For Your Next Test

1. Dead zones are commonly found in coastal areas and estuaries where nutrient runoff from agriculture is high.
2. The process leading to dead zones is called eutrophication, which starts with nutrient enrichment.
3. Hypoxia, or low oxygen levels, is the primary condition characterizing a dead zone.
4. Dead zones can significantly impact local fisheries and biodiversity, leading to economic consequences.
5. Notable examples include the Gulf of Mexico dead zone at the mouth of the Mississippi River.

Review Questions

• What causes the formation of dead zones in aquatic environments?
• How does eutrophication contribute to the development of dead zones?
• What are some ecological and economic impacts of dead zones?

Related terms

Eutrophication:

The process by which a body of water becomes overly enriched with nutrients, leading to excessive growth of algae.

Hypoxia: A condition in which there is insufficient oxygen in a body of water to support marine life.

Nutrient Pollution: The presence of excess nutrients, primarily nitrogen and phosphorus, in water bodies often due to agricultural runoff.