College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
School for Environment and Sustainability, University of Michigan, Ann Arbor 48109, USA.
Sci Total Environ. 2018 May 1;622-623:702-709. doi: 10.1016/j.scitotenv.2017.12.045. Epub 2017 Dec 13.
Intensive animal husbandry had aroused great environmental concerns in many developed countries. However, some developing countries are still undergoing the environmental pollution from livestock and poultry sectors. Driven by the large demand, China has experienced a remarkable increase in dairy and meat production, especially in the transformation stage from conventional household breeding to large-scale industrial breeding. At the same time, a large amount of manure from the livestock and poultry sector is released into waterbodies and soil, causing eutrophication and soil degradation. This condition will be reinforced in the large-scale cultivation where the amount of manure exceeds the soil nutrient capacity, if not treated or utilized properly. Our research aims to analyze whether the transformation of raising scale would be beneficial to the environment as well as present the latest status of livestock and poultry sectors in China. The estimation of the pollutants generated and discharged from livestock and poultry sector in China will facilitate the legislation of manure management. This paper analyzes the pollutants generated from the manure of the five principal commercial animals in different farming practices. The results show that the fattening pigs contribute almost half of the pollutants released from manure. Moreover, the beef cattle exert the largest environmental impact for unitary production, about 2-3 times of pork and 5-20 times of chicken. The animals raised with large-scale feedlots practice generate fewer pollutants than those raised in households. The shift towards industrial production of livestock and poultry is easier to manage from the environmental perspective, but adequate large-scale cultivation is encouraged. Regulation control, manure treatment and financial subsidies for the manure treatment and utilization are recommended to achieve the ecological agriculture in China.
集约化畜牧业在许多发达国家引起了极大的环境关注。然而,一些发展中国家仍在遭受来自畜牧业的环境污染。在中国,巨大的需求推动了乳制品和肉类产量的显著增长,尤其是在从传统家庭养殖向大规模工业养殖转型的阶段。与此同时,大量的禽畜粪便被排放到水体和土壤中,导致富营养化和土壤退化。如果不对其进行适当的处理或利用,这种情况将在大规模养殖中加剧,因为此时粪便的数量超过了土壤的养分承载能力。我们的研究旨在分析养殖规模的转变是否有利于环境,并介绍中国畜牧业的最新状况。对中国畜牧业产生和排放的污染物进行估计,将有助于制定粪便管理法规。本文分析了不同养殖方式下五种主要商业动物的粪便产生的污染物。结果表明,育肥猪产生的污染物几乎占粪便排放总量的一半。此外,每单位产量的肉牛对环境的影响最大,约为猪肉的 2-3 倍,鸡肉的 5-20 倍。与家庭养殖相比,采用大规模饲料场养殖的动物产生的污染物较少。从环境角度来看,向畜牧业的工业化生产转变更容易管理,但应鼓励进行充足的大规模养殖。建议进行法规控制、粪便处理和财政补贴,以促进中国的生态农业发展。