Question

based on the information provided, what is consumed as large amounts of algae are decomposed?
eutrophication is the process by which a body of water becomes overly enriched with nutrients, leading to excessive plant growth and algae blooms that deplete oxygen in the water. this over - enrichment often occurs due to runoff from land, carrying fertilizers and waste into water bodies. as the algae and plant matter die, they decompose, a process that consumes significant amounts of oxygen, resulting in low oxygen levels in the water. these low oxygen conditions create dead zones, areas in water bodies where aquatic life cannot survive.
for example, algae in a lake might bloom excessively due to high levels of nitrogen and phosphorus from agricultural runoff. this algae then dies and decomposes, a process that consumes oxygen and creates a dead zone. fish and other aquatic life either leave the area or die due to lack of oxygen.

Explanation:

The text explains that as algae decompose in the process of eutrophication, oxygen is consumed, leading to low - oxygen levels and 'dead zones'.

Answer:

Oxygen