Which of the following conditions is likely to result in high leaching?

High leaching occurs when water carries away dissolved substances, such as nutrients or pesticides, from the soil. The condition that is most likely to lead to high leaching is associated with sandy soil combined with low organic matter and a low water table.

Sandy soil has larger particle sizes and greater pore spaces, which allows water to drain quickly. When combined with low organic matter, the soil provides little in the way of nutrients or retention of water, leading to rapid movement of water through the soil profile. Additionally, having a low water table means that there is less groundwater close to the surface to impede downward flow, facilitating further leaching as water and its dissolved materials move downwards through the soil layer.

In contrast, the other soil types mentioned have properties that either retain water more effectively or do not allow for rapid leaching. Heavy clay soils, for example, retain more moisture and nutrients, whereas dense, compacted soils may restrict water flow and nutrient transport. Silty soils with high moisture content can also impede the leaching process due to water saturation, leading to reduced movement of substances.

Thus, the combination of sandy soil, low organic matter, and a low water table effectively creates conditions that promote high leaching.