Assessment of trace gases, carbon and nitrogen emissions from field burning of agricultural residues in India

Field burning of crop residue (FBCR) is becoming a growing environmental concern in developing countries. In this instance, a comprehensive crop-wise and spatially distributed study on the FBCR emissions from India for the period 1980 through 2010 have been undertaken, that covers: residue generation, its types, use pattern, and estimates of carbon, nitrogen, CH4, CO, N2O and NOX emissions; along with associated uncertainties. FBCR contributed about 44 and 14% of the non-biofuel biomass and total biomass burning, respectively in India in the year 2000. The total dry residue generated are estimated as 217, 239 and 253 Tg, of which 45, 60 and 63 Tg of dry biomass are estimated to be subjected to FBCR in the years 1994, 2005 and 2010, respectively. Wheat and rice crops together accounted for about 76% of this. Burning of such huge amount of biomass is estimated to emit 22.4, 24.4 and 26.1 Tg of carbon; 0.30, 0.33 and 0.35 Tg of nitrogen; 4.18, 4.59 and 4.86 Tg carbon dioxide equivalent of greenhouse gases (GHG, viz., CH4 and N2O; which is over 1% of the Indian agriculture sector GHG emissions); 2951, 3,240 and 3,431 Gg of CO; and 120.8, 132.9 and 140.6 Gg NOx emissions in 1994, 2005 and 2010, respectively. Further, the Indian states of U.P, Punjab, Haryana, M.P, Maharashtra, T.N, Karnataka, Andhra Pradesh, Bihar and W.B have been found to contribute maximum to the Indian FBCR emissions. FBCR avoidance and optimum utilization of crop-residue resource is urgently required for agro-ecosystem sustainability in the region.