Which process involves the movement of pesticides through soil with water?

Leaching is the process where soluble substances, including pesticides, move through the soil profile with the flow of water. When it rains or when irrigation occurs, water percolates through the soil, picking up dissolved compounds as it moves downward. This movement can transport pesticides away from the site of application, potentially leading to contamination of groundwater resources if not properly managed. Leaching is an important consideration in agricultural practices, as it affects both environmental safety and the efficacy of pest control strategies.

In contrast, volatilization refers to the conversion of pesticides from liquid or solid form into gaseous form, which can happen when they are exposed to air, particularly in warm temperatures. Chemical degradation involves the breakdown of pesticides through various chemical reactions, altering their structure and potentially reducing their effectiveness. Microbial degradation involves the action of microorganisms that break down pesticides into less harmful components, which is a natural process occurring in the soil but does not specifically relate to the movement of pesticides through soil with water. Each of these other processes plays a role in the overall fate of pesticides in the environment, but they do not describe the specific movement of pesticides driven by water.