Factors of Soil Erosion

Soil Characteristics

• Soil can be classified into three main categories; clay, silt and sand. Extremely fine soils that have a high content of silt-sized particles can be picked up by winds or runoff and carried long distances. Medium-sized particles, like clay or sand, may be lifted and carried short distances by wind and are more resistant to erosion by water. Sand and loam soils are more resistant to both types of erosion than silt, fine sands and clay soils because they have a greater amount of organic material and larger particles.

  The soil's ability to resist erosion depends on the grouping of its particles as well. Significant amounts of compaction and cultivation may cause soil to lose its ability to stick together, making it more vulnerable to erosion.

Slope of the Land

• The higher the slope of the land, the more chance there will be for erosion. Soil erosion increases with the slope incline and its length. This is because runoff flows at greater speeds, which makes it more able to carry sediment away.

Organic Content

• Organic materials act like glue. They help to bind the particles in the soil together, making it more resistant to erosion. The amount of organic material in a type of soil also affects the soil's ability to absorb water, which can reduce runoff and make it less likely to be carried away by wind.

Vegetation

• Soil that has very little or no vegetation will erode faster than soil with a cover of plants or crops. Plant cover prevents raindrops from splashing directly onto the soil and slows the speed of runoff. This allows the water to penetrate the soil rather than push it away. Vegetation also protects the soil from wind. The plant roots help to bind the soil, improving the soil structure and making it more erosion-resistant. Plants close to the surface, like grass, are most effective in slowing runoff and preventing erosion.

Climate

• Periods of heat and drought, during which the top layer of soil becomes dry and loose, can result in significant amounts of erosion by wind. This can also happen during the winter in areas where the soil is dry. Frozen soil is more resistant to water erosion, but rapid thaws can lead to significant damage. The temperature or climate also affects the organic material within the soil. Warmer climates have a thinner top layer, where organic matter collects, making these soils more vulnerable to erosion.