Which of the following pathways is of most concern for loss of phosphate from a recently tilled soil?

The pathway of most concern for the loss of phosphate from recently tilled soil is erosion. After tillage, the soil structure is often destabilized, making it more susceptible to erosion by both water and wind. Phosphate, being bound to soil particles, can be easily detached and transported by surface water or wind during these erosive processes.

When soil is disturbed by tillage, the protective aggregation of soil particles is disrupted, leaving them vulnerable. Erosion can lead to significant loss of nutrient-rich topsoil, which is essential for plant growth. Phosphate is especially crucial for plant development, as it plays a key role in energy transfer, photosynthesis, and nutrient movement within plants.

Other pathways such as leaching—where water-soluble substances are washed away from the soil—are generally not a major concern for phosphate, as it tends to bind strongly to soil particles and is less mobile in groundwater compared to nitrogen. Surface runoff can contribute to phosphate loss, but the particles carrying phosphate can more readily be lost through erosion, particularly in a recently tilled environment. Volatilization is not a significant concern for phosphate since this pathway is related to gases escaping from the soil rather than the loss of solid-bound phosphates.

Understanding these concepts allows