In situ incorporation of biomass and crop residues for improving soil health

Climate Vulnerability

Drought, high temperature stress, flood and heat wave

Existing Practice

Generally, farmers burn crop residues like stalks of pigeonpea and cotton without recycling them. This is a great loss to the farmer as well to the land, as the land is deprived of biomass, which helps build precious soil organic carbon. This harmful practice is leading to increased CO₂ emissions beside depriving crop residue to the soil. Farmers resort to burning of the crop residue as removing it involves higher costs for labour to uproot, chop and mix in the soil.

Resilient practice / technology

In order to encourage farmers to change this practice, rotavator machine was introduced in the NICRA villages. The harvested crop stalks/ stubbles are chopped into small pieces and incorporated in-situ into the soil with varying efficiencies depending upon the left over residue. The cost of implement is Rs. 1.0 to Rs.1.2 lakhs and field capacity of the rotavator is 5-6 ha/day. Rotavator helps in obtaining of early seedbed preparation soon after harvesting of kharif crops for sowing of rabi crops. This not only requires low energy in tillage operation but also mixes and incorporates the stubbles of previous crop thoroughly in the soil. This improves the soil physical properties and hence, results in increased crop yield. Incorporation of green manuring crops such as daincha, moong and cowpea in wet conditions can be taken up to improve soil health.

Impact

On an average incorporation of cotton stalks in one hectare field adds about 124 Kg N, 36 Kg P₂O₅, with some quantities of Zn, S and other micronutrients into the soil. This results in saving of chemical fertilizers, labour and time. Residue or biomass incorporation improves water retention of soils and benefits the crop. This practice of in situ incorporation of crop residues can bring about reduction in the harmful practice of residue burning which aggravates GHG emissions and air pollution. Rotavator use is gaining popularity in view of its multiple operation capabilities with greater efficiency. In NICRA villages the machine was made available through custom hiring centers for wider adoption by farmers of resource conservation practices for improvement of soil health and productivity.

Shri Sanjay Sawalkar, a farmer of Takali village, Amravati, Maharashtra cultivates about 2.4 ha of land out of which 0.8 ha is irrigated. He earlier practiced burning of cotton stalk after harvesting the crop. His average yield of seed cotton was 8.8 q/ha. In the next season tillage operations such as plouging and harrowing with tractor mounting implements cost him Rs 2500/ha. Under the NICRA project he hired the rotavator from the custom hiring center for incorporating the crop residue in the field and spent around Rs 1750/ha for the operation. His average productivity in subsequent years increased by 2.7 q/ha.

Scope for upscaling

In NICRA villages, in situ incorporation of paddy, wheat and cotton residues and biomass of green manuring crops was demonstrated in 1166 ha covering 1698 farmers across several districts: Faridkot, Aurangabad, Buxar, Saran, Jehnabad, Koderma, Malda, Supaul, Kushinagar, Amravati, Baramati, Gondia, Kurnool, Nalgonda, Bharatpur, Kota, Kutch, Bilaspur, Dantewada, Chitrakoot, Datia, Guna, Belgaum and Namakkal.

Source: Smart Practices and Technologies for Climate Resilient Agriculture