Negative Impacts of Soil Erosion

Fertility Loss

• The bulk of the nutrients that plants require for healthy growth is found in the upper layer of soil known as topsoil. This layer of the soil mainly consists of decayed organic material, which supplies the bulk of the nutrients found in topsoil. When erosion carries away all or part of this layer of soil the amount of nutrients available for plants is substantially decreased. The thickness of the topsoil layer has a direct impact on the amount of plant growth it can support.

Soil Structure

• Eroded soil also has a lower carrying capacity for water. This limits the amount of water that the soil can carry, further reducing the amount of plant life the soil can support. The reduced carrying capacity of the soil also reduces the amount of rainwater that the earth can absorb making areas that are denuded of topsoil more susceptible to flash flooding during periods of heavy rainfall.

Water Pollution

• Soil erosion pollutes water sources in several ways. Heavy rainfall that dislodges large amounts of topsoil will clog waterways with sediment, harming aquatic life and rendering the water unusable. When this occurs, the eroded soil also carries any chemicals that were suspended in the soil into the water. Chemical fertilizers, herbicides and pesticides that have eroded or leached from lawns or farmlands further pollute water sources, causing algae to bloom and killing aquatic animals.

Controlling Erosion

• Erosion is not completely preventable; however, there are several land management practices you can use to limit it. In gardens or areas where the soil is disturbed, limit the depth of your digging or tilling to reduce the amount of loose soil that erosion can carry away. If you have drainage ditches in your yard, promote a healthy layer of grass or another ground cover in the bottom of the ditch to hold the soil in place. During the winter months, grow a layer of winter grass over your garden to stabilize the soil and hold it in place.