| Environmental problems of livestock and poultry raising is one of issues be confronted with developed and developing countries, manure disposal is a worldwide problem and a critical problem of taking the low-carbon agricultural road in our country. Livestock feed consumption needs a guarantee from a certain amount of planting output, while livestock pollution needs a certain scale of planting to consume and contain. The mismatch between regional planting and breeding industries is one reason of livestock and poultry raising pollution. At present, there are many study achievements about environment carrying capacity in domestic and foreign areas(such as land, population, ecology, water resources, tourism resources and so on), except the environmental capacity of livestock and poultry raising.In order to building livable city, breeding industry not only has been quitted the main eight urban area entirely but also the thought of despise and abandon even combat animal husbandry occurred frequently in Beijing. Beijing should retain a certain scale of animal husbandry which contribute to the environment improvement and agriculture sustainable development form the view of circular economy and environment carrying capacity.This paper chose 13 counties in Beijing as the research objects, and assumed that agricultural land of each county as a large "farmland" matching raising farm. Hypothesised that all the livestock and poultry manure was the only source of fertilizer used for returning applications. Calculated the environment carrying capacity of livestock and poultry in 13 countries via the method of nitrogen balance between planting and breeding industry, and divided different five alarm levels which determine a raising farm scale reasonable weather or not. So, carrying capacity and alarm levels provide scientific basis for decision-making department in Beijing.Overall, this study achieved the following results:1,Improved the concepts of environment carrying capacity of livestock and poultry as well as standard livestock, advanced the calculation of standard livestock on the basis of previous researches,2,Calculated the conversion coefficient of standard livestock quantitatively through countryside investigation, measurement and expert consultation based on livestocks' nitrogen excretions. Result is that,1 standard cow=23.11 standard pig=2.65 standard sheep=497.59 standard chicken=226.01 standard duck.3,Under the current cropping system, calculated the crop nitrogen needs and soil nitrogen of 13 countries quantitatively in order to achieve the largest nitrogen of manure which crop required as well as the environmental carrying capacity of livestock and poultry in each country. Determined the value of environmental carrying capacity of livestock and poultry, and divided alarm levels. Analysis shows, currently, the livestock raising in Beijing have been overloaded in mild degree from the overall, and maldistribution in 13 countries. Tongzhou and Daxing are the countries matching between planting and breeding industries relatively, others exist mismatch in different degrees, the scale of livestock and poultry breeding should be greater efforts to control in Mentougou, Shunyi, Fangshan, Changping and Miyun; breeding scale should be enlarged in Pinggu, Huairou and Yanqing; Breeding scale should retain and appropriately increase in the areas of Chaoyang, Haidian and Fengtai, which have large planting and far away from the city.Each counties in Beijing suburb develop breeding industry within the environmental carrying capacity of livestock and poultry would not damage the ecological environment but promote the benign circulation between planting and breeding industries so long as collecting and disposing livestock and poultry manure reasonably, furthermore, it will best for the improvement of agricultural ecological environment, and increasing the ecological functions of Beijing, changing the existing misunderstanding of "culture=pollution" consequently in the capital.
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