Emergy Analysis of Agriculture-Livestock-Fisheries Compound Ecological Breeding System

Ecological breeding is an important way to alleviate pollution from livestock and poultry breeding. Taking the Wuhan Yinhe Pig Farm as an example, the ecological breeding system of this Pig Farm was compared with the pig-only breeding system which used to be in operation before, and evaluated with the emergy analysis method. It was found that the former was much superior to the latter in minimization of resource consumption and environmental loading and in production efficiency. In terms of minimization of resource consumption, the former was 1.77% in emergy self-sufficiency rate, slightly higher than the latter(0.27%), the former was 98.09% in purchased-emergy rate, slightly lower than the latter(99.74%), the former was 5.69% in feedback-emergy rate, higher than the latter(0.00%) and the former was 5.80% in waste recycling rate, higher than the latter(0.00%). In terms of environmental loading, the ecological breeding system was 85.72% in environmental loading rate, lower than the pig-only breeding system(116.04%), and the former was 56.93% in system input renewal rate, higher than the latter(50.09%). And in terms of production efficiency, the former was 2.07 in net-emergy output rate, slightly higher than the latter(1.93). Moreover, the ecological breeding system was significantly higher in economic benefit than the pig-only breeding system.