Why Soil Erosion is a Major Challenge for Sustainable Soil Management

Despite almost a century of research and extension efforts, soil erosion by water, wind, and tillage continues to be the greatest threat to soil health and soil ecosystem services in many regions of the world. Our understanding of the physical processes of erosion and the controls on those processes has been firmly established. Nevertheless, some elements remain controversial. It is often these controversial questions that hamper efforts to implement sound erosion control measures in many areas of the world.
In the next series of blogs, we will explore the intricacies of Soil Erosion and try to understand deeply the causes, effects, and possible actions that could be taken to deal with this issue.

• What is soil erosion?

  Soil erosion is the displacement of the upper layer of soil, one form of soil degradation. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice (glaciers), snow, air (wind), plants, animals, and humans.

  Soil erosion is a naturally occurring geomorphic process, but human use of the soil typically results in rates of soil detachment and transport that are many times the naturally occurring rates.

  Causes of Soil Erosion

  Flooding due to heavy rainfall:
  The high intensity of rainfall causes soil erosion. There are four types of soil erosion due to rainfall: Sheet erosion. Splash erosion, Rill erosion, and Gully erosion. Eroded soil gets washed away into the nearby streams and rivers due to the high amount of rainfall. The higher the amount of Rainfall higher the soil erosion.

  Agricultural activities:
  Another main cause of soil erosion is farming practices, they disturb the ground. The trees are cut down and the lands are plowed for the germination of new seeds. Most crops are grown during springs and most of the soil is eroded during winters because the land lies fallow during winters.

  Grazing:
  The grazing animals remove the plants or vegetation from the land through their feeding habit at a place. The only left is topsoil. They also pull out plants by their roots, due to which soil loosens up and more erosion will occur.

  Mining:
  In the Mining process, a large number of trees are cut down to make the field fit for logging. due to which soil gets lost and erosion occurs frequently.

  Constructional activities:
  The construction also leads to soil erosion. for construction purposes, the forests and grasslands are cleared which exposes the soil making it more favorable to erosion.

• Agricultural Practices That Cause Soil Erosion

  Natural vegetation is by far better protection than crops because farmlands are more vulnerable to rainfall and winds. Besides, agricultural practices can cause soil erosion due to a reduction of biodiversity both in vegetation variety and soil microorganisms. In turn, a lack of organic matter and beneficial biota negatively impacts field fertility because not only earth particles but nutrients are taken away from bare fields.

  The primary causes of soil erosion due to poor farm management are excessive fertilization or irrigation, conventional tillage, monocropping, overgrazing, and more. Let’s consider the impact of separate farming practices on erosive processes.

• Does monocropping cause soil erosion?
  Monocropping, or monoculture, implies growing the same crop for several seasons. Since each crop requires particular nutrients, this practice causes field depletion. Consequently, it may result in land degradation and soil erosion.

  Can conventional tillage cause erosion in fields?
  It can. In particular, moldboard plowing makes the earth loose contributing to agricultural soil erosion by water and winds. Conversely, no-till farming prevents these processes.

  Do fertilizers cause soil erosion?
  It may happen. Excessive use of mineral fertilizers under insufficient organic fertilization leads to dehumidification and destruction of its structure, which makes it more vulnerable to erosive processes.

  Does irrigation cause soil erosion?
  Sometimes it can. Artificial irrigation is the only way to produce crops under a lack of natural water supply but excessive irrigation can cause topsoil erosion. It refers to surface irrigation when nutrients and topsoil particles are removed from uneven fields.

  Does overgrazing cause soil erosion?
  It does. Livestock overgrazing is a vivid example of poor pasture management that destroys topsoil cover promoting erosive processes. Rotational grazing and cover crops can solve the problem.

  Does terrace farming cause soil erosion?
  It doesn’t. On the contrary, terrace farming prevents erosion by slowing down water streams on even platforms.



• Solutions To Soil Erosion

• Decision-making in soil erosion control depends on factors like the soil type, topography, or climate specifics, and applied agricultural practices like tillage systems or crop rotation. It is important to analyze the effectiveness of undertaken methods and try to adjust them for individual fields.

  Success starts with early problem detection and the choice of suitable methods depends on its severity. For example, replanting, cover crops, or mulching can be good ways to reduce soil erosion in the initial stages because vegetation protects fields from destruction by water run-offs, raindrops, and wind. In severe cases, the impact can be mitigated with terrace farming or check dams.

  Other soil erosion control measures include contour cropping and planting perennials with strong root systems to fix the ground and slow down water streams.