What is a common result of increased nutrient runoff into water bodies?

Increased nutrient runoff into water bodies, particularly from sources like fertilizers, septic systems, and agricultural practices, often leads to a phenomenon known as eutrophication. This process stimulates the excessive growth of aquatic plants, especially algae and invasive aquatic weeds, due to the surplus nutrients, particularly nitrogen and phosphorus.

When these nutrients enter the water, they encourage rapid plant growth, which can overwhelm the ecosystem. This excessive growth can lead to several secondary issues, such as depletion of oxygen in the water as the plants die off and decompose, which can harm fish and other aquatic organisms. It can also create an imbalance in the aquatic ecosystem, disrupting the natural habitats and contributing to negative environmental impacts like harmful algal blooms.

Conversely, the other options do not accurately reflect the effects of nutrient runoff. Decreased plant growth would not be a result of increased nutrients; rather, it typically leads to an opposite effect. More balanced ecosystems would not occur due to excess nutrients; instead, the ecosystem becomes unbalanced. Improved water quality is also unlikely, as nutrient runoff generally degrades water quality by promoting harmful growths and oxygen depletion.