What is the outcome of eutrophication on aquatic environments?

Eutrophication leads to the process where water bodies become overly enriched with nutrients, particularly nitrogen and phosphorus. This influx of nutrients often results in excessive growth of algae, commonly referred to as algal blooms. While this might at first seem beneficial, the growth of algae can be detrimental to aquatic environments.

As algal blooms proliferate and subsequently die off, the decay process is facilitated by bacteria that consume dissolved oxygen in the water, leading to a significant decrease in oxygen levels. This reduction can create hypoxic, or even anoxic conditions, where the oxygen is insufficient to support most aquatic life. Fish and other organisms that rely on oxygen to survive can experience stress or die off in these conditions, negatively impacting the ecosystem.

Thus, the correct outcome of eutrophication is that it results in decreased oxygen levels in aquatic environments, significantly affecting biodiversity and overall aquatic health.