Dead zones resulting from hypoxia and anoxia:
A) are prevalent in coastal waters west of the Mississippi River delta during the summer months.
B) increase the standing stock of demersal fishes.
C) occur exclusively in estuarine environments.
D) result from significant inputs of organic hydrocarbons in marine environments.
E) stimulate high primary productivity in coastal areas.

Question

Quizplus · Accepted Answer

Dead zones resulting from hypoxia and anoxia are prevalent in coastal waters west of the Mississippi River delta during the summer months due to excessive nutrient pollution from agricultural and urban runoff, which leads to algal blooms and subsequent oxygen depletion.

Answer: B, E
 Dead zones do not increase the standing stock of demersal fishes but conversely have negative impacts on fish and marine life. Dead zones do stimulate high primary productivity in coastal areas due to algal blooms, but this also leads to oxygen depletion and subsequent dead zones.

Dead Zones Resulting from Hypoxia and Anoxia