SOIL EROSION AND CONSERVATION

SOIL EROSION AND CONSERVATION

The denudation of the soil cover and subsequent washing down is described as soil erosion. The processes of soil formation and erosion, go on simultaneously and generally there is a balance between the two. Sometimes, this balance is disturbed due to human activities like deforestation, over-grazing, construction and mining etc., while natural forces like wind, glacier and water lead to soil erosion. The running water cuts through the clayey soils and makes deep channels as gullies. The land becomes unfit for cultivation and is known as bad land.

Figure 1.10: Soil Erosion

In the Chambal basin such lands are called ravines. Sometimes water flows as a sheet over large areas down a slope. In such cases the top soil is washed away. This is known as sheet erosion. Wind blows loose soil off flat or sloping land known as wind erosion. Soil erosion is also caused due to defective methods of farming. Ploughing in a wrong way i.e. up and down the slope form channels for the quick flow of water leading to soil erosion. 

Figure 1.11: Gully Erosion

Ploughing along the contour lines can decelerate the flow of water down the slopes. This is called contour ploughing. Steps can be cut out on the slopes making terraces. Terrace cultivation restricts erosion. Western and central Himalayas have well developed terrace farming. Large fields can be divided into strips. Strips of grass are left to grow between the crops. This breaks up the force of the wind. This method is known as strip cropping. Planting lines of trees to create shelter also works in a similar way. Rows of such trees are called shelter belts. These shelter belts have contributed significantly to the stabilisation of sand dunes and in stabilising the desert in western India.

State of India’s Environment

*   The village of Sukhomajri and the district of Jhabua have shown that it is possible to reverse land degradation. Tree density in Sukhomajri increased from 13 per hectare in 1976 to 1,272 per hectare in 1992;

*   Regeneration of the environment leads to economic well-being, as a result of greater resource availability, improved agriculture and animal care, and consequently, increased incomes. Average annual household income in Sukhomajri ranged from Rs 10,000-15,000 between 1979 and 1984;

*   People’s management is essential for ecological restoration. With people being made the decision-makers by the Madhya Pradesh government, 2.9 million hectares or about 1 percent of India’s land area, are being greened across the state through watershed management

The Citizens’ Fifth Report,1999 Centre of Science and Environment (CSE), New Delhi

Source: This topic is taken from NCERT TEXTBOOK