Soil is vital to human life as it impacts major ecosystem services such as food, water quality, groundwater, stream flow and soil erosion. Soil plays a very important role in supplying nutrients and favourable physicochemical conditions to plant growth, promoting and sustaining crop production, providing habitat for soil organisms, reducing environmental pollution, resisting degradation and maintaining or improving human and animal health. The major challenges impacting the soil ecosystem are rainfed farming, high soil erosion and climate risks, and lack of understanding about soil health and low crop yields. Land degradation worldwide is considered to be the major reason for low productivity. The current agricultural practices and climate challenges are causing soil erosion faster than the natural process of replenishment of soils. Estimates indicate that nearly 50 percent of the irrigated land in arid and semi-arid regions have some degree of salinization. As per Indian Council of Agricultural Research (ICAR) reports, the area under problem soils has increased from 220 lakh hectares (2005) to 243 lakh hectares (2010). This indicates that there is scope for improving the health of problem soils in India and sustaining it by creating awareness, promoting regenerative practices, and monitoring for ensuring healthy and secure food and water, carbon sequestration, a healthy environment, and an ecosystem. Sustainable soil health management contributes to Sustainable Development Goals 2, 3 6, 13, and 15.
Soil Organic Carbon (SOC) is an important soil health indicator for its contribution to food production, climate change adaptation and mitigation. SOC can be lost as CO2 or CH4 can be emitted back into the atmosphere as eroded soil material or dissolved organic carbon washed into rivers and oceans.
Why is soil health important?
SOC management worldwide plays an important role in voluntary carbon markets as it is linked with carbon stocks. The turnover which may be in a few months, years, or for an even longer duration, fetches carbon credits to farmers. The factors affecting SOC are climate- extreme events like drought, flood and rise in temperature, land use, vegetation, Hydrology (Water content) and Soil texture.
Practices to convert soil into net carbon sinks:
- Soil conservation measures such as contour bunds, vegetation/plantation/grass development on bunds, silvopasture, agroforestry, afforestation and forest conservation.
- Ensure proper drainage conditions in waterlogged soils, particularly in wetlands and rice fields which are the largest sources of methane emissions.
- Application of water in required quantity as well as quality.
- Integration of organic fertilizer and manure
- Use of vermicompost and biochar produced from unused crop residues and green manuring.
- Cover crops, crop rotation, and crop diversification.
- Integrated Pest Management.
- Supply balance plant nutrients based on soil tests and nutrient analysis.
Rambhau Wagh, a farmer from Parkhed village near Khamgaon, Buldhana district of Maharashtra, owns 1.2 ha land. He has always been encountering low productivity and high production cost. On realising the importance of healthy soils, he took up vermicompost production and sold the surplus to nearby farmers.
