The Assessment Of Livestock And Poultry Breeding Cross

Livestock and poultry breeding pollution has become one of the main reasons for non-point source pollution. Currently, major pollution control technologies focus on pollution control of single environmental medium, but ignore the cross-medium pollution in the process of livestock and poultry breeding and lack systematic and comprehensive prevention thought, while in developed countries such as European Union, the United States, a large number of cross-medium researches have carried out and best feasible legal documents such as technical reference have formed. This thesis, in allusion of cross-medium pollution of livestock and poultry breeding and combining China’s laws and regulations and the current situation of pollution prevention and control, investigated more than40typical livestock and poultry breeding enterprises of different types of technology, scale and regional characteristics, carried out the evaluation research of cross-medium pollution prevention technology of livestock and poultry breeding, established life cycle assessment model of cross-medium pollution of livestock and poultry breeding, systematically evaluated the ecological environment problem of livestock and poultry breeding. The main achievements of research are as follows:Based on the life cycle assessment theory of EDIP2003and combining the characteristics of China’s cross-medium pollution of livestock and poultry breeding, research methods such as literature research, field research, expert scoring and public survey were used and life cycle assessment model of cross-medium pollution of livestock and poultry breeding was established. Besides, through the deep investigation and field testing of livestock and poultry breeding enterprises of two types including biogas engineering type and biological fermentation bed type, analytic hierarchy process was used to calculate the total amount of pollution in the different stages of livestock and poultry breeding and a comparison analysis of current situation of cross-medium pollution, its impact on the environment and economic benefit between two types was carried out.According to the established evaluation model and characteristics of cross-medium pollution, livestock and poultry breeding is divided into three different systems including raw material system, breeding system and waste treatment system. By using both quantitative and qualitative method, the cross-medium pollution of two types from four perspectives of environmental acidification, greenhouse effect, consumption of non-renewable energy and eutrophication is evaluated. Through the characteristics and normalization of four elements, the degree of impact on the environment was quantified. The results of impact potential of four elements of biogas engineering type are:ED:5.15×10-3; GWP:1.73×10-2;AP:4.30×10-2and EP:1.38×10-3; and results of biological fermentation bed type are:ED:7.25×10-3;GWP:1.35×10-2;AP:3.22×10-2å'ŒEP:4.55×10-3. The rating of potential impact of four elements caused by two techniques rank on environment is environmental acidification, greenhouse effect, consumption of non-renewable energy and eutrophication in turn.The results of comparison analysis of impact potential of two techniques on environment reveal that production of raw material has the largest impact on the environment in the life cycle due to large consumption and long production chain; in the link of pig breeding, greenhouse gas emission is the main factor of influence the environment; in the link of waste disposal, the impact on environment mainly embodies in environmental acidification and greenhouse effect. Biological fermentation bed technology, as the result of its simple waste disposal, short production chain and relatively less feedstuff consumption under the same productivity, has smaller impact on environment than biogas engineering.