Spatiotemporal dynamics of greenhouse gases emissions from livestock and poultry in Beijing area during 1978-2009

Livestock production, especially its intensification around metropolitan areas, has contributed immensely to global warming. The estimation and analysis of spatial and temporal patterns of greenhouse gas emissions from livestock and poultry production were critical for the formulation of mitigation and adaptation strategies of national agricultural sectors. To investigate greenhouse gas emissions from enteric fermentation and manure management of livestock and poultry industry in Beijing area, emissions of methane and nitrous oxide during 1978-2009 were estimated based on regional livestock statistics. The study used the emission factor method recommended by the 2006 IPCC Guidelines and specific emphasis was placed on the trends and spatial distributions of the emissions. The results showed that livestock and poultry emissions in Beijing area started increasing at the early 1990s and peaked in 2004, with an average annual growth rate of 2%. This trend was similar to the increase in livestock and poultry population in Beijing area. Among the emissions, enteric fermentation methane was the most significant, with annual average emission of 0.4 Tg CO2-eq. Cattle was the main contributor to enteric fermentation methane emission, accounting for 54%, followed by swine and sheep. The annual average emissions of methane and nitrous oxide from manure management were 0.2 Tg CO2-eq and 0.3 Tg CO2-eq, respectively. The emissions were mainly from swine, respectively accounting for 73% and 46% of the emitted methane and nitrous oxide. Increase in methane indicated the intensification of livestock and poultry industry in Beijing area during 1978-2009. CR4 (industry concentration index) increased progressively from 1978 to 2009, indicating unceasing enhancement of the intensity of livestock industry in Beijing area. The emissions were mainly from Shunyi, Daxing, Miyun and Tongzhou Districts. The estimated livestock methane and nitrous oxide emissions in Beijing area for 1978-2009 was consistent with the linear growth model. Although an arduous task, it was urgent for the Beijing livestock industry to adopt efficient reduction strategies of greenhouse gases emission.