Understanding Soil Erosion and its Impact on Farming.
                     Understanding Soil Erosion 
and its Impact on Farming
Soil Erosion
• Soil erosion is a gradual process that occurs when the impact of water or 
wind detaches and removes soil particles, causing the soil to deteriorate. 
Source: crops.extension.iastate.edu
Human induced soil erosion
• Human induced soil erosion and associated damage to all agricultural land 
over many years have resulted in the loss of valuable agricultural land due to 
abandonment and reduced productivity of the remaining land which is partly 
made up for by the addition of nitrogen and phosphate fertilizers.
Source: www.mdpi.com
CAUSES OF EROSION
Soil Structure
• Soil structure influences the ease with which soil can be eroded. Soils with a 
medium to fine texture, a low level of organic matter content, and weak 
structural development are most easily eroded
Source: www.mdpi.com
Land Topography
• The topography of a given landscape, its rainfall and/or wind exposure all 
combine to influence the land’s susceptibility to soil erosion.
• Erosion rates are high especially on marginal and steep lands which have 
been converted from forests to crops 
Source: www.mdpi.com
EFFECTS OF SOIL EROSION 
Water Availability
• During soil erosion by rainfall, water runoff significantly increases with less 
water entering the soil and less water available to support the growing 
vegetation.
Source: www.mdpi.com
Nutrient Losses
• Eroded soil carries away vital plant nutrients such as nitrogen, phosphorus, 
potassium, and calcium. 
• Typically, the eroded soil contains about three times more nutrients per unit 
weight than are left in the remaining soil.
Source: www.mdpi.com
Soil Organic Matter
• Soil organic matter is a valuable resource because it facilitates the formation of soil 
aggregates and thereby increases soil porosity. 
• Once the organic matter layer is depleted, the productivity of the ecosystem, as measured 
by plant biomass, declines both because of the degraded soil structure and the depletion 
of nutrients that were contained in the organic matter.
Source: www.mdpi.com
Soil Depth
• When erosion substantially reduces soil depth of from 30 cm for deep soils to 
even less than 1 cm for thin soils, plant root space can be minimized, and the 
plants could be stunted.
Source: www.mdpi.com
The Future
• Worldwide, soil erosion continues unabated while the human population continues to 
increase rapidly and 66% of the world population is now malnourished. 
• If soil conservation is ignored and population control is ignored, more malnourished 
people and more deaths will occur.
Source: www.mdpi.com