Wind erosion can often be described by two types: sweeping drift and active drift. Sweeping drift is wind erosion that is relatively gentle and causes loose, fine soil to go into suspension but with minimal development of drift banks. An active drift is wind erosion that is more vigorous. This type of wind erosion involves the three particle movement processes (surface creep, saltation and suspension), and drift banks or blowouts, also called deflation basins, develop.
Wind erosion removes topsoil, the layer of soil with the greatest amount of organic matter, biological activity and nutrients, which creates a poor environment for plant growth. Wind erosion can break down soil structure, thus exposing organic matter within soil aggregates to decomposition and loss. Wind erosion can decrease soil depths, thus reducing the amount of air, water and nutrients available for plant growth. The dust from wind erosion can affect animal and human health.
For wind erosion to occur, wind speed at the soil surface must be sufficient to lift and transport soil particles. Physical or biological crust-crushing, such as heavy grazing or vehicle and foot traffic, can cause particle movement to begin at lower wind speeds. Wind erosion can occur when there is bare soil due to the reduction in plant cover, biological crusts and litter.
Increasing soil cohesion can help improve soil structure, which can help reduce wind erosion. Increasing the roughness of the soil surface is another way to help control wind erosion. Increasing plant cover can help reduce wind speed, thus decreasing wind erosion. Areas that have a high level of violent winds should use methods such as hedges and windbreaks -- for example, two rows of large trees surrounded by two rows of low trees.