Life Cycle Assessment of the Chinese Commercial Pig

As world population continues to increase, global demand for livestock products are expected to increase by 70% by 2050. Due to this rising demand, reducing the environmental impacts of livestock production is an important part of building a robust, sustainable food system for future generations. Currently, China produces over 50% of the world’s swine, but the environmental impact of Chinese pig production has not been quantified. The objective of this study was to conduct an attributional, cradle to farm gate Life Cycle Assessment (LCA) compliant to ISO standards (ISO 14040/44) and LEAP guidelines (FAO 2015) of commercial pig production, as it is becoming the more common type of production system. This study analyzed the Global Warming Potential (IPCC 2006) of a market chain producing pigs with a final market weight of 1 metric ton (t). Primary data on commercial pig production characteristics in China was collected from a feed producer with locations across China. The system boundary of this study included production of feeds, preparation of feeds at feed mills, animal husbandry and manure management, and all upstream processes. The global warming potential (GWP) for 1 ton pig live weight (LW) at the farm gate was 2.95 metric tons of carbon dioxide equivalents (CO₂e). The GWP to produce one ton pig LW in China is 27% higher than that of producing 1 ton LW in North America (Kebreab et al. 2015), and higher than the values reported in the same study for Europe, North American and South America (2.1, 2.3, and 2.6 t CO₂e / t LW respectively). The major contributors to GWP were feed production (38%), manure management and storage (33%), and energy used for animal housing (19%). Within feed production, corn and soybean meal contributed the most to GWP, due to their respective carbon footprints and percentage in the diet. Emissions from feed production were larger than those of Europe, South America, and North America, due to higher Chinese emission factors. The Chinese electricity grid produces close to 50% more emissions per kWh than those of the US; therefore, processes requiring electricity, will be higher for the Chinese equivalent (e.g. fertilizers, pesticides, amino acids, phytase, heating, cooling, and lighting) than for other countries. This study serves as a baseline for the environmental impacts of commercial pig production in China, and could contribute to future research into targeted mitigation of emissions.