Erosion

The erosion is a natural process of the Earth ‘s crust that occurs when rocks and soil detach from the surface land in which are usually located and transferred to another. It is responsible for changing the landscape through the erosion of the mountains, the filling of valleys and because it causes rivers to rise and fall. In general, it is a fairly slow and gradual process that can even take thousands or millions of years. But erosion can sometimes be accelerated by human activitiessuch as agriculture and mining. Erosion begins with a process called weathering ; In this process, environmental factors are responsible for breaking rocks and soil into smaller pieces, and loosen them from the surface of the earth, facilitating their transport.

What is erosion?

It consists of the degradation of the soil of the earth’s crust by means of different factors such as water and air. It occurs with greater force in places where the lands are very arid and dry , and when there is not abundant vegetation, the soil is more exposed. It is part of the process of morphogenesis by means of which the forms of the earth are modified and molded.

Erosion process

The erosion process is responsible for moving pieces of rock or soil from one place to another. Most of the erosion is carried out by the effect of water ( this being the most important ) , wind or ice . These forces are responsible for transporting rocks and soil fragments from the places where they were originally found, to different ones. A sign of erosion is when we see muddy water . The brown color that water takes indicates that pieces of rock and earth are suspended in the water and that they are transported from one place to another. This transported material is calledsediment . When the wind or water is slow or when the ice melts, the sediments are deposited in a new place. As the sediment accumulates, more fertile soil forms in the new place. The basins of the rivers are made almost entirely of sediment.

Types

There are different types of erosion among which we have the following:

• Water or hydric erosion : moving water is the main agent of erosion. The rain manages to break up and carry pieces of earth and slowly washes the rock fragments. The currents of rivers wear its banks, creating valleys becoming larger. The impact of the raindrops on the surface also generates the detachment and dragging of the sediments.
• Wind erosion : The wind can carry dust, sand and volcanic ash from one place to another. In drier areas, the sand is blown away by the wind and the wind hits the rock, slowly wearing it down. It occurs mainly in deserts .
• Chemical erosion :  this type of erosion is what causes chemical changes in rocks through different components such as oxygen, carbon dioxide and water that trigger different reactions. The rocks then crumble and travel to different places.
• Geological erosion : it occurs through energy from the sun that causes the layers of air and water on the earth to move and this causes the surface of the earth to become flatter, eroding and transporting sediments to different places.
• Biotic erosion : chemical processes of rocks such as heat, cold, water, biological compounds and chemical reactions that water produces in rocks are involved. It depends on the weather and temperature.
• Gravitational erosion : it happens when given clearance to bottom of rocks and sediments by gravity . The materials are then moved from the higher parts to lower places where rivers and glaciers collect the materials and move them to even lower places.

Causes

There can be several causes that cause erosion. The deforestation is one of them, when soils have sufficient trees the increases erosion. The bad uses that occur in the area of agriculture cause an acceleration of erosion, including the plowing of soils and grazing . The droughts produce loosen soils and sediments are moved elsewhere. There are also some human activities that produce erosion, mining , river diversions, occupation of river beds by buildings that cause vegetation and humidity decrease by increasing erosion.

Consequences of erosion

As a consequence of erosion, there is the partial or total loss of the soils and with it all the ecosystems of a certain place are altered , mainly the aquatic one, since the dragging of sediments modifies the waters, making them cloudy and dirty. The flora and fauna are reduced and there is a slow loss of fertility in the soil, with them, the costs of agriculture increase considerably and the inhabitants must move to different places due to the impoverishment of the areas.

Examples

Through water erosion we can see rocks in a rounded shape as a result of dragging and erosion. The soils that are under a waterfall are worn away by the direct fall of the water. The deserts are an example of erosion caused by the wind, its results are long – term, for example, the sand dunes in the desert. When the glaciers melt , the rocks crack.