Managing CO2 emission from groundwater pumping for irrigating major crops in trans indo-gangetic plains of India

摘要

Groundwater irrigation and energy played an important role in increasing agricultural production and food security in India; however, declining groundwater levels result in an increase of energy consumption and CO2 emission for lifting water. This, in the future, is expected to influence groundwater development and usage policy in India. This study was undertaken to assess the CO2 emission from groundwater irrigation in an agriculturally dominant district, Karnal of Haryana in India, and to explore the possibility of reducing CO2 emission through various management alternatives. This study indicates that the CO2 emission from groundwater irrigation for baseline scenario is the highest for sugarcane (93 kgCO(2)/ha/m) followed by rice (40 kgCO(2)/ha/m), wheat (28 kgCO(2)/ha/m), mustard (26 kgCO(2)/ha/m), pigeon pea (14 kgCO(2)/ha/m) and pearl millet (4 kgCO(2)/ha/m). However, on a district level, the total CO2 emission under the baseline scenario is highest for rice (140,655 Mt) followed by wheat (98,153 Mt) and sugarcane (18,416 Mt). Higher CO2 emissions from rice and wheat are due to more area under these crops. Results also indicate that CO2 emission can be reduced by 32 % by improving pump efficiency from 34.7 to 51 %. Results show that by improving irrigation efficiency in rice by 15 % and in other crops by 20 % over the baseline efficiency, CO2 emissions can be reduced by 23 % in rice and 25 % in other crops. By improving the pump set and irrigation efficiencies together up to the achievable level, CO2 emissions can be reduced up to 48 % for rice and other crops.