The treatment and disposal of livestock manure have become a bottleneck that limits the development of the breeding industry in a green and sustainable way In recent years, China has attached great importance to the development of ecological circular agriculture Biogas treatment has arisen as an important way to manage livestock manure By utilizing manure to produce biogas and then promoting the use of biogas, rural areas can greatly reduce the use of fuel and coal Rural sanitation and living environment can be improved, and soil health and plant growth can also benefit from the provision of biogas slurry nutrient If well managed, the biogas can provide an effective and efficient alternative in support of green and ecological agriculture development Hainan Province is a tropical island in China Tropical cash crops, and livestock and poultry farming are the major income sources for Hainan farmers Located in the north of Yazhou District, Sanya City, Hainan Province, Beiling Village is home to 3 857 famers, including 3 852 from the Li ethnic minority, accounting for 99 9 percent of the total Local villagers rely on mango and banana as the main cash crops.