Key Points
Key Points: Land Degradation
- Land degradation
Land degradation is the general wearing away and loss of productivity of land due to factors such as salinization, erosion, deforestation, flooding, water-logging and unplanned urbanization. - Importance of top soil
The fertile top soil (15–20 cm thick) contains essential plant nutrients, and its degradation directly reduces agricultural productivity. - Soil salinization
Soil salinization is caused by the accumulation of soluble salts (mainly sodium, calcium and magnesium salts) which adversely affect soil structure and crop yield. - Causes of salinization
Salinization occurs due to inadequate leaching in semi-arid regions, rising and fluctuating groundwater table, rapid evaporation, saline irrigation water, canal seepage and seawater intrusion in coastal areas. - Extent and impact in India
About 7 million hectares of land in India are salt-affected, especially in coastal, arid, semi-arid and Indo-Gangetic regions, posing a serious threat to sustainable agriculture.
