What is runoff in the context of pesticide application?

Runoff in the context of pesticide application refers to the movement of water over the surface of the land, which can carry pesticides and other pollutants into water bodies such as rivers, streams, or lakes. When pesticides are applied to agricultural fields or landscapes, rain or irrigation can cause water to flow over the surface, picking up these chemicals. This movement can result in contamination of adjacent water resources, posing risks to aquatic ecosystems and potentially affecting drinking water supplies.

Choosing surface movement into water as the correct answer emphasizes the importance of understanding how water interacts with pesticides after application and highlights the need for best management practices to minimize environmental impacts. Such practices might include maintaining buffer zones, timing applications carefully, and using appropriate techniques to reduce runoff.