Analysis of the types of animal husbandry and planting that influence household biogas in rural China

Abstract

Producing biogas from agricultural waste by using a household biogas digester has a critical role in increasing energy supply and reducing greenhouse gas emissions in rural areas. However, only a few studies have analyzed the type of animal husbandry and planting that influence household biogas. This paper analyzes the spatial-temporal distribution of household biogas and its proportion in the total biogas produced in rural China from 2009 to 2018. The correlation between household biogas in rural China and animal husbandry and planting from 2009 to 2018 is also examined. The types of animal husbandry and planting that influence household biogas are then respectively determined via ordinary least squares and geographically weighted regression. Results show that the spatial-temporal distributions of household biogas with maximum and minimum values of 1.384 × 1010 m3 in 2011 and 0.8420 × 1010 m3 in 2018, respectively and its proportion with maximum and minimum values of 94.83% in 2009 and 75.07% in 2018, respectively significantly vary and show a declining trend from 2009 to 2018. The number of cattle and pigs is identified as the main animal husbandry factor that influences household biogas, whereas the planting areas of vegetables, fiber, and tobacco were identified to be the main planting factors. Considering fitting effects, R2 and adjusted R2 values of 0.8620 and 0.8100 obtained by geographically weighted regression respectively, were higher than those of ordinary least squares (0.6480 and 0.6220, respectively), respectively in animal husbandry factors, whereas R2 and adjusted R2 values of 0.8400 and 0.7990 obtained by geographically weighted regression, respectively, were higher than those of ordinary least squares (0.7190 and 0.6880, respectively) in planting factors. These results provide a reference for planning the production of biogas and the utilization of agricultural waste.