We explain what soil erosion is, how it is classified and what its causes are. Also, its consequences and how to avoid it.
What is soil erosion?
Soil erosion is the process of erosion of the earth’s surface as a consequence of the impact of geological actions (such as water currents or thaws), climatic (such as rains or intense winds) or by human activity (such as agriculture, deforestation, expansion of cities, among others ).
Soil erosion is a slow and discontinuous phenomenon that consists of the mobilization of detachments from the surface and that, in the long term, generates changes in the aspect of the land. There are cases in which erosion occurs in an accelerated manner due to natural disasters or excessive human actions, which causes soil degradation with loss of organic matter and minerals.
Types of soil erosion
There are three main types of natural soil erosion:
- Water erosion. It is produced by the passage of water flow that can be pluvial or fluvial.
- Wind erosion. It is produced by the wind that blows strongly.
- Gravitational erosion. It is produced by the action of gravity before the fall of rocks or the melting of glaciers, from the top of a slope.
There is another type of soil erosion that occurs more rapidly:
- Anthropic erosion. It is produced by human activity that impacts the wear and tear and deterioration of the soil such as, for example, intensive agriculture, deforestation, the construction of canals and routes, the expansion of urban areas, intensive livestock farming, mining, among the main ones.
Causes of soil erosion
The causes of soil erosion can be diverse and the main ones include:
- The movement of water. In the form of rains, rivers or ocean currents, the water hits the ground and detaches part of the surface, which is carried away by the current.
- The movement of the wind. The blow of strong winds against the ground, detaches particles and debris from the surface (in the form of dust, sand or rocks) and moves them.
- The movement of rocks and glaciers. The release of ice on glaciers or rocks that descend from the top of a slope, causes wear or cracks in its path.
- Exposure to extreme temperatures. Extremely hot or cold weather conditions that occur for a long time, alter the surface of the soil and cause cracks or ruptures that facilitate wear.
- The use and abuse of the land by humans. Excessive human activity, such as intensive agriculture or the construction of urban areas, causes the deterioration of the soil, in many cases, with irreversible damage.
Consequences of soil erosion
The main consequences of soil erosion due to human action, involve:
- The loss of fertile land yield for the sustainability of agricultural ecosystems and for land productivity.
- The increase in pollution and sedimentation of streams and rivers, causes a decrease in the species that live there.
- The desertification of the soil turns the land into an arid area or not suitable for life (due to the lack of water, vegetation and food).
- The reduction of the filtering capacity in desertified soils can generate floods in the area.
- The imbalance of the ecosystem generates loss of biodiversity, that is, of animal and plant populations.
- The global climate is altered, to a great extent, by the reduction of forests that have the capacity to absorb carbon dioxide.
How to avoid soil erosion?
To avoid erosion and soil wear due to human actions, the best solution is prevention and the development of activities such as:
- Sustainable land use. It can help reduce the impacts of agriculture and livestock, and prevent soil degradation from nutrient loss.
- The reforestation. The planting of trees and plants favors the restoration of ecosystems and the maintenance of the soil.
- Vegetation planting. Encouraging sustainable planting in exposed territories or areas where construction machinery was deployed, helps to stabilize the land and its nutrients.
- The construction of drainage channels. In areas where the soil has little absorption capacity, drains can help channel water to prevent flooding.
Deforestation and soil erosion
Deforestation is human-caused action that consists of clearing forests and jungles by cutting or burning. If this action is carried out intensively and is not followed by the practice of adequate reforestation, it generates serious damage to the soil and the ecosystem, among which the following stand out:
- The loss of habitat for millions of animal and plant species. It is the most dramatic impact because living beings cannot survive the destruction of their environment.
- Climate change. The indiscriminate felling of trees alters the climatic conditions, because they protect the soil and maintain the humidity of the environment and the hydrological cycle that returns steam to the atmosphere.
- A greater greenhouse effect. In addition to intervening in the climate, trees absorb the gases that cause global warming. Its absence, due to indiscriminate felling, alters the concentration of gases in the atmosphere.
Vegetation maintains the properties of the soil, prevents erosion, occupies a key place in the water cycle – and consequently in the climate – and conserves biodiversity. Therefore, to maintain the harmony of the ecosystem, the care and maintenance of the soil is essential.