QAL Laws & Regulation Practice Exam

Which factor plays a significant role in pesticide leaching?

1. Soil texture and composition

2. Time of year

3. Weather patterns

4. Pesticide brand and type

The correct answer is: Soil texture and composition

Soil texture and composition significantly influence pesticide leaching due to their effects on water retention and movement within the soil profile. For example, sandy soils, which have larger particles and greater pore spaces, allow water – and any dissolved pesticides – to move more quickly through the soil compared to clay soils, which are finer and retain more water. The composition of the soil, including its organic matter content, can also affect how well pesticides bind to soil particles. Soils rich in organic matter often enhance pesticide absorption, reducing the leaching potential. Although the time of year, weather patterns, and the specific brand and type of pesticide can affect the leaching process, they do so in a secondary manner compared to the foundational role that soil characteristics play. The interactions between these other factors and soil texture and composition can vary significantly, but without the right soil conditions, the potential for leaching is inherently limited. Understanding these soil properties is crucial for effective pesticide management and minimizing environmental impact.