EVALUATION OF GREENHOUSE GAS EMISSIONS FROM THREE CONTRASTING INTEGRATED CROP AND LIVESTOCK PRODUCTION SYSTEMS DURING 1991-2016 IN GANSU OF CHINA

Abstract

This study was to evaluate the difference in greenhouse gas (GHG) emissions from 3 contrasting integrated crop and livestock production systems in Gansu of China from 1991 to 2016 using the life cycle assessment technique. The three systems were located in different regions: Hexi Oasis (dry arid, intensive crop/livestock production), Loess Plateau (semi-arid/semi-humid, dominated by extensive crop production) and Qinling Bashan Mountains (moist-subtropical, extensive crop/livestock production). The data used were collated from 525 farms (35 farms/county and 5 counties/region) thorough official statistical records and farm survey. The ANOVA analysis of average data from 2012 to 2016 indicated that Loess Plateau had a higher CO2 equivalent (CO2-eq) emission factor per kg DM product of maize and flaxseed than other 2 regions (P< 0.05), while a lower rate per kg beef carcass weight. Qinling Bashan Mountains had a lower emission factor for producing 1 ¥ of crop products than other 2 regions (P< 0.05). The evaluation of change in GHG emissions from 1991 to 2016 indicated that CO2-eq per kg carcass of pork, beef, and lamb in the 3 production systems generally declined during this period, but emissions per kg DM of potato, rapeseed, and maize increased. However, CO2-eq per ¥ of crop and livestock products tended to decrease from 1991 to 2016, driven mainly by market price and productivity. The present results provide the benchmark information for local policy makers and agricultural industries to make informed decisions for mitigation of GHG emissions from agricultural production in Gansu of China.