Types of soil movement.

Wind Erosion (Aeolian Erosion)

Wind erosion is a common problem, especially in arid and semi-arid regions. It occurs when the wind moves loose soil particles from one place to another. The major forms of wind erosion are:

• Saltation: Fine particles (usually sand) bounce along the surface of the soil.
• Suspension: Lighter particles (like dust and silt) are lifted and carried by the wind over long distances.
• Creep: Larger particles, like gravel, roll along the surface of the soil.

ICAR Recommendations: To reduce wind erosion, ICAR recommends the use of windbreaks (tree plantations or artificial barriers), maintaining soil cover, and adopting soil conservation practices like mulching and proper irrigation techniques.

Water Erosion

Water erosion is the removal of soil by the forces of rainfall and runoff. It occurs in three major forms:

• Sheet Erosion: The removal of a thin layer of soil across a large area, often imperceptible, but it leads to significant soil loss over time.
• Rill Erosion: When runoff water forms small channels or rills on the soil surface, making them more pronounced over time.
• Gully Erosion: Larger and deeper channels, known as gullies, are formed due to concentrated water flow.
• Splash Erosion: Caused by the impact of raindrops dislodging soil particles.

ICAR Recommendations: ICAR suggests practices like terracing, contour plowing, and constructing check dams to control water runoff and soil erosion. Agroforestry and the establishment of vegetative cover are also recommended.

Gravitational Movement (Mass Movement)

Gravitational movement refers to the downward movement of soil and debris, typically on slopes or steep areas, due to the force of gravity. The main forms are:

• Creep: The slow, gradual movement of soil down a slope, usually imperceptible over short periods.
• Slumping: The downward movement of soil or rock in a rotational manner, often triggered by rainfall or other disturbances.
• Landslides: Sudden, rapid movements of large quantities of soil and rock, typically on steep slopes.
• Mudflows: Rapid flows of wet soil, rocks, and debris, often occurring after heavy rainfall.

ICAR Recommendations: ICAR advises the use of soil conservation measures such as terracing, slope stabilization with vegetation, and the construction of check dams to reduce the risk of landslides and other mass movements.

Biological Movement

Soil movement can also be driven by living organisms, such as plants, animals, and microorganisms. Some examples include:

• Earthworm Activity: Earthworms burrow through the soil, mixing it and creating channels that help water and air to penetrate deeper into the soil.
• Plant Root Movement: Roots grow and penetrate through soil, sometimes breaking up compacted layers and facilitating the movement of soil particles.
• Insect and Animal Activity: Burrowing animals like rodents and insects also contribute to soil movement, creating channels and mixing soil.

ICAR Recommendations: ICAR encourages practices that enhance biological soil movement, such as maintaining soil organic matter, promoting earthworm populations, and incorporating cover crops.

Human-Induced Soil Movement

Human activities can exacerbate soil movement, especially through activities like farming, construction, and deforestation. Some common human-induced movements are:

• Plowing: Agricultural plowing can loosen the soil, making it more susceptible to wind and water erosion.
• Deforestation: The removal of trees reduces soil stability, leading to increased soil erosion and landslides.
• Construction and Mining: Excavation and construction activities disturb the soil, causing displacement and erosion.

ICAR Recommendations: To minimize human-induced soil movement, ICAR advocates for sustainable farming practices, afforestation, agroforestry, and responsible land management. No-till farming, contour farming, and maintaining vegetative cover are highly recommended.

Floodwater Movement

Floodwater movement refers to the transfer of soil during flood events. It often leads to the erosion of topsoil and the deposition of sediment in new areas. This can impact agricultural productivity.

ICAR Recommendations: The development of flood management systems like flood control reservoirs, embankments, and better drainage systems are essential to minimize floodwater-induced soil movement. ICAR also emphasizes the need for rainwater harvesting and floodwater storage.