Erosion is a naturally occurring process. Erosion has given us some of our most beautiful landscapes. There are beautiful erosion formations such as the Grand Canyon and Bryce Canyon, Utah. Erosion is the loosening, transportation, and relocation of soil particles from one place to another. Erosion occurs primarily due to the action of wind and water. The rate and extent of erosion are determined by soil type and condition, slope of the land, plant cover, land use, and climate. Erosion does not occur only on wilderness landscapes, and the effects are not always positive, especially when you are talking about productive topsoil. Landslides, can bury towns and claim thousands of lives. Streams or rivers loaded with eroded soil can turn sources of clean drinking water into major health hazards.
Water erosion includes raindrop splash, sheet erosion, rill erosion, gully erosion, and slumping or mass erosion. Raindrop splash is the most obvious on bare ground during a torrential rainstorm. The raindrops strike the ground and upon impact break soil particles apart, splashing these particles into the air. The impact of raindrops can be lessened by plant cover. Plants break the fall of the raindrops and allow for water infiltration or percolation.
Sheet erosion is the washing away of a thin surface layer of soil over a large area of land. Because sheet erosion occurs evenly, it is generally not obvious until most of the topsoil is removed.
Rill erosion may be noticeable on sloping bare ground after a rainstorm. Water forms small, well-defined channels that carry soil away from the sides and bottom of these channels. The rills of channels erode more soil as they move downslope and increase in size. When rills become large, the process is called gully erosion. This severe form of soil erosion removes tons of soil from the sidewalls and bottom of the gully.
Streambank erosion (and similarly, coastal erosion) is the cutting away of the banks by water. It is generally a slow process which represents the normal situation occurring along most streams. It is most active during floods when the amount and velocity of water are the greatest and when the bank soils are submerged under water and saturated.
To control erosion, plant cover is usually the best solution. But to grow our food farmers make furrows in the land for row crops. A farmer can use a variety of methods to “keep soil in its place.” A farmer may plant their crops around the curve of a hill rather than up and down the hill, this is called contour planting. Plowing will also be done on the contour. Farmers may also build terraces. Terraces are wide ridges that go around a hill to prevent water from rushing down the hill too fast. On steep hillsides, rather than clear the area for cropland, farmers will maintain the area in forest and grass. Water always runs downhill, so farmers do not plow in low areas where water collects; instead they maintain low ditch areas as grassed waterways. Soils susceptible to wind erosion should be kept covered with some kind of vegetation. If this cannot be done year-round, a windbreak of trees and shrubs may be planted. Windbreaks are rows of trees planted to slow down the wind and prevent soils from blowing away in the wind.
