Waste from livestock and poultry breeding and its potential assessment of biogas energy in rural China

Global livestock and poultry industry is growing continuously, with large amounts of excreta produced. These wastes could be either important anaerobic fermentation materials of biogas energy or, if discharged into the environment without appropriate processing, serious pollution sources to soil and water systems. In developing countries, rural energy poverty is currently a major threat to sustainable development and livelihoods. Hence, the availability of clean, affordable and reliable energy is of significant concern in both policy and scholarly circles. Moreover, pollutants related with animal husbandry have been identified as one of the dominant contributors to contamination of water systems, such as surface water eutrophication and groundwater nitrate enrichment. Consequently, assessing waste from livestock and poultry breeding and the associated biogas systems is of critical essence in rural energy and environmental decision-making. The present study concentrates on a Chinese context and attempts to explicitly investigate Environmental Kuznets Curve (EKC) applying heterogeneous panel cointegration methods, combining with distribution and characteristics of waste from livestock and poultry breeding for China's 31 provincial economies from 1991 to 2013. And, potentiality of biogas energy and its CO2 emission reduction based on the utilization of waste is assessed. The empirical results indicate an inverted U-shaped Environmental Kuznets Curve in N indicator resulting from livestock and poultry breeding, where value of the turning point is approximately CNY 51,800. With economic growth and consumptive change, problems arising from animal husbandry mode can be increasingly great. There will be many major challenges to address these special environmental issues in rural area, especially in Central China and West China. Biogas production by animal excreta could be one of the most important rural energies and waste treatment patterns, which could reach 63.65 billion m3 in 2013, equivalent to approximately 20% of natural gas used, and might offer a GHG reduction of more than 220 million tons of CO2 eq. China should assign greater importance to special agricultural pollution and energy options in rural communities, in addition to 'beautiful countryside' propaganda.