Human Causes of Erosion

The following list gives an overview of human actions, which can cause erosion and therefore lead to soil degradation:

• Poor agricultural practices such as ploughing soil to support cultivated plants or ploughing soil in areas where rainfall is insufficient to support continuous plant growth
• Exposing soil on slopes
• Removal of forest vegetation
• Overgrazing
• Altering the characteristics of streams which cause bank erosion
• Causing increased peak water discharges (increased erosion power) due to changes in hydrological regimes, by such means as altering the efficiency of channels (channel straightening)
• Reducing evapotranspiration losses as a consequence of vegetation removal
• Production of impervious surfaces such as roads and footpaths, preventing infiltration into the soil and causing increased runoff into streams.

Control of Erosion

As erosion is caused by the effects of wind and water, in general control methods aim to modify these effects. The following list describes some of the most common control methods:

• Prevention of soil detachment by the use of cover materials such as plants
• Crop production techniques (e.g. fertilizing with organic fertilizer), to improve soil characteristics and promote plant growth and hence surface cover
• Ploughing to destroy rills and contour planting to create small dams across a field, to retard or impound water flow
• Filling small gullies with mechanical equipment or conversion into a protected or grassed waterway
• Terracing of slopes to reduce rates of runoff
• Prevention of erosion in the first place by careful selection of land use practices
• Conservation tillage methods
• Armoring of channels with rocks, tires, concrete and timber to prevent bank erosion
• The use of wind breaks to modify wind action
• Ploughing clod sizes too big to be eroded, or ploughing ridges.

(ACS 2009)