soilerosion

Soil erosion is the process by which the upper soil layer is worn away and removed from land by natural forces such as water and wind, as well as by human activities. It reduces soil depth, structure, and fertility and can lead to sedimentation in downstream water bodies.

The main erosion pathways are water erosion, including sheet, rill, and gully erosion, and wind erosion, including deflation and abrasion. Water erosion is driven by rainfall impact and surface runoff, while wind erosion occurs on loose, dry soils with little vegetation. Susceptible factors include soil texture, organic matter, slope, rainfall intensity, and land management.

Impacts include loss of productive soil, reduced water infiltration and storage, nutrient depletion, and degraded water quality due to sedimentation and nutrient loading. Erosion also increases flood risk and can cause dust generation in dry regions.

Erosion rates are typically measured in tons per hectare per year. Management strategies aim to reduce erosion by maintaining cover and soil structure: crop residues, cover crops, terracing, contour farming, strip cropping, reduced tillage or no-till, mulching, windbreaks, proper irrigation scheduling, and controlled grazing. At larger scales, engineered structures and sustainable land-use planning are implemented.

Soil erosion is a major component of land degradation and is addressed in soil conservation and watershed management programs around the world.