Soil Erosion and It's Types

 The word erosion has been derived from the Latin word „erodere‟ which means eating away or to excavate. The word erosion was first used in geology for describing the term hollow created by water.

Soil Erosion is defined as the detachment of soil particles, their transportation from one place to another, and deposition elsewhere through water, wind, coastal waves, snow, gravity, and other forces. It is a two-phase process involving the detachment of individual soil particles from soil mass, transporting it from one place to another (by the action of any one of the agents of erosion, viz; water, wind, ice, or gravity) and its deposition. When sufficient energy is not available to transport a particle, a third phase known as deposition occurs.

In general, finer soil particles get eroded more easily than coarse particles (silt is more easily eroded than sand).

Major erosive agents are impacting raindrops and runoff water flowing over the soil surface.

Types of Soil Erosion

According to Origin: Soil erosion can broadly be categorized into two types i.e. geologic erosion and accelerated erosion.

1. Geological Erosion: It refers to natural or normal erosion. Under natural undisturbed conditions, equilibrium is established between the climate of a place and the vegetative cover that protects the soil layer. The loss of soil is compensated by the formation of new soil under natural weathering processes.

2. Accelerated Erosion: When soil erosion exceeds the normal rate and becomes unusually destructive and unproductive. When land is put under cultivation, the natural balance existing between the soil, its vegetation cover, and climate is disturbed.

According to Erosion Agents: Soil erosion is broadly categorized into different types depending on the agent which triggers the erosion activity. Mentioned below are the four main types of soil erosion.

1. Water Erosion: Water erosion is seen in many parts of the world. In fact, running water is the most common agent of soil erosion. This includes rivers that erode the river basin, rainwater which erodes various landforms, and the sea waves which erode the coastal areas. Water erodes and transports soil particles from a higher altitude and deposits them in low-lying areas.

2. Wind Erosion: Wind erosion is most often witnessed in dry areas wherein strong winds brush against various landforms, cutting through them and loosening the soil particles, which are lifted and transported towards the direction in which the wind blows.

3. Glacial Erosion: Glacial erosion, also referred to as ice erosion, is common in cold regions at high altitudes. When soil comes in contact with large moving glaciers, it sticks to the base of these glaciers. This is eventually transported with the glaciers, and as they start melting it is deposited in the course of the moving chunks of ice.

4. Gravitational Erosion: Although gravitational erosion is not as common a phenomenon as water erosion, it can cause huge damage to natural, as well as man-made structures. It is basically the mass movement of soil due to gravitational force. The best examples of this are landslides and slumps.

Agents of Soil Erosion: The soil erosion agent can be classified and summarized as shown in Fig.






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