Study Title: “Geospatial Modelling and Mapping of Soil Erosion in India”.
Key Findings on Soil Erosion in India
- High Susceptibility Areas: 9 out of the 20 most erosion-prone districts in India are in Assam.
- Vulnerable Districts in Assam: Goalpara, Dhubri, Chirang, Baksa, Kokrajhar, Bongaigaon, Udalguri, Nalbari, Barpeta.
- Other Vulnerable States: Meghalaya, Himachal Pradesh, Jammu & Kashmir (3 districts each).
- Extent of Erosion:
- 46% of India’s landmass faces minor erosion.
- 17% experiences catastrophic erosion (E6 category).
Brahmaputra Basin & Other River Basins
- Brahmaputra Basin: Highest erosion rate – 64 t/ha/yr.
- Other River Basins:
- Mahanadi – 42 t/ha/yr.
- Ganga – 07 t/ha/yr.
- Non-Indus basin – least erosion (3.22 t/ha/yr).
- E6 Category Areas (Catastrophic Erosion):
- Covers 5% of India’s landmass.
- Found in Assam, Meghalaya, Himachal Pradesh.
- Causes deep gullies, infrastructure damage (roads, buildings, fences, etc.).
Causes of Soil Erosion
- High PSL (Potential Soil Loss) Values:
- Brahmaputra & Ganga Basins: New soil layers form annually due to floods but are highly erodible.
- Heavy Rainfall: Rainfall erosivity (R-factor) is the primary contributor to erosion.
- Topographic Factor: Steep slopes increase erosion vulnerability.
Impact on Agriculture
- 78 million hectares of agricultural land affected.
- 8% average productivity loss due to soil erosion.
Ways to Control Soil Erosion
Vegetative Measures
- Afforestation & Reforestation: Planting trees and vegetation to bind soil.
- Cover Crops: Growing crops like grasses and legumes to protect topsoil.
- Contour Farming: Plowing along natural land contours to reduce runoff.
- Strip Cropping: Alternating different crops in strips to minimize erosion.
Structural Measures
- Terracing: Creating step-like fields on slopes to slow water runoff.
- Check Dams & Gully Plugging: Constructing small dams in gullies to slow erosion.
- Windbreaks & Shelterbelts: Planting trees as barriers to reduce wind erosion.
- Silt Traps & Sediment Basins: Capturing eroded soil before it reaches water bodies.
Soil Management Techniques
- Mulching: Covering soil with organic material (straw, leaves) to reduce water impact.
- Conservation Tillage: Minimizing plowing to maintain soil structure.
- Crop Rotation: Alternating crops to maintain soil fertility and structure.
- Agroforestry: Combining trees with crops for better soil stability.
Water Management Strategies
- Rainwater Harvesting: Collecting rainwater to prevent excessive surface runoff.
- Drainage Control: Constructing proper drainage to reduce water accumulation.
- Percolation Pits & Recharge Wells: Enhancing groundwater recharge.
Policy & Awareness Initiatives
- Land Use Planning: Implementing zoning laws to prevent deforestation.
- Soil Conservation Programs: Government initiatives promoting sustainable farming.
- Community Participation: Involving local communities in conservation efforts.
- Education & Training: Raising awareness about soil conservation methods.
