What is a consequence of high nitrogen and phosphorus levels in water bodies?

High nitrogen and phosphorus levels in water bodies can lead to excessive aquatic plant growth, a phenomenon often referred to as eutrophication. These nutrients serve as fertilizers for algae and aquatic plants, promoting their rapid growth and proliferation. When these plants accumulate in large quantities, they can cause several environmental issues.

Excessive plant growth can block sunlight from reaching other aquatic life, disrupting ecosystems and harming fish and other organisms that rely on light for survival. When these plants die and decompose, it can deplete oxygen levels in the water, leading to hypoxic conditions that can be detrimental to aquatic life.

In contrast to the other options, high nutrient levels do not filter out harmful substances, do not prevent pest growth, and do not stabilize food chains. Instead, they disrupt ecological balance, highlighting the importance of managing nutrient levels in aquatic ecosystems.