During algae blooms, what critical environmental issue may occur?

The occurrence of oxygen depletion during algae blooms is a critical environmental issue because when algae proliferate excessively, they consume a significant amount of dissolved oxygen in the water as they later decompose. This rapid decomposition process, primarily performed by bacteria, can create a severe drop in oxygen levels, particularly in deeper water where mixing is limited. Such low oxygen conditions, often referred to as hypoxia, can lead to fish kills and the death of other aquatic organisms that depend on oxygen for survival.

Additionally, the resulting dead zones can disrupt the entire aquatic ecosystem, affecting species diversity, food webs, and the overall health of the water body. Therefore, understanding the dynamics of oxygen levels during algae blooms is vital for managing aquatic environments and preventing detrimental impacts on fish populations and other aquatic life.