Question

1. describe how the amount of nutrients in water create dead zones.

Explanation:

Excess nutrients (like nitrogen, phosphorus) in water (from runoff, sewage) cause algal blooms. When algae die, decomposers (bacteria) break them down, using up dissolved oxygen via respiration. Low oxygen levels (hypoxia) kill or drive away aquatic life, creating dead zones.

Answer:

Excess nutrients (e.g., nitrogen, phosphorus) in water (from sources like agricultural runoff, sewage) trigger algal blooms. When these algae die, decomposer bacteria break them down, consuming large amounts of dissolved oxygen through respiration. This leads to hypoxia (low oxygen levels) in the water, which kills or displaces most aquatic organisms, forming a dead zone.