The carbon footprint of agricultural crop cultivation in India
The present assess the green house gas (GHG) emission from cultivation over the past 50 years in India. Emission has increased by 161% over 50 years from 14.81 TgCE/year (0.12 tCE ha−1yr−1) in 1960 to 38.71 TgCE/year (0.28 tCE ha−1yr−1) by 2010. This is due to increase in the use of inputs primarily; chemical nitrogen fertilizer, shifting from conventional animal and human energy sources to carbon-intensive diesel and electricity-dependent machineries. It is also due to 16% decrease in area of less carbon-intensive coarse cereals and 22% increase in rice cultivation. Among crops, rice recorded maximum emission (23.75 Tg CE/ha) while it was lowest in redgram (2.98 Tg CE/ha). Nitrogen among inputs, accounted for 92 and 83% emission between 1960 and 2010 respectively while, nitrogen use efficiency declined, suggesting loss of added nitrogen to atmosphere as N2O. Methane accounted for 90 and 58% of emission over 1960 and 2010, respectively, indicating a declining trend over the years. Thus, amending nitrogen fertilizer use and measures to reduce methane emission alone can substantially reduce the carbon footprint of the crop cultivation process. There is also ample scope for reducing emissions from energy sources.
