When Certain Bodies of Water Develop Regions Known as "Dead

Question

When certain bodies of water develop regions known as "dead zones" it often means that:
A)oxygen has been depleted.
B)carbon dioxide is not available.
C)nitrogen has become limited.
D)phosphorus has killed animals.
E)plant life no longer can survivE.

Accepted Answer

Dead zones occur when there is a significant decrease or depletion of oxygen in the surrounding water. This can happen when there is an excess of nutrients, usually nitrogen or phosphorus, which leads to an overgrowth of algae. When the algae die and decompose, bacteria consume the oxygen leading to a hypoxic or anoxic environment. This lack of oxygen can result in the death of fish and other aquatic organisms.