Systems Dynamic Digraph Analysis of Scale Pig Production Development in Center China

Scale pig production is an effective approach to improve farmers＇ income. Many pig feeding villages and intensive pig farms has presented rapidly in Center China in recent years, the focus of large quantity of manure and sewage discharged by pig farms has become the leading source of pollution in vast rural areas. How to dissolve the contravention between the development of scale pig production and the serious pollution caused by swine excreta in rural area is a complex systematic problem. An approach named Systems Dynamic Digraph Analysis Approach is presented in this paper. And the approach is applied to analyze the scale pig breeding system in small hill watershed area systematically. A case of Pingxiang Taihua pig farm in the west region of Jinggang Mountain, which is a typical intensive pig farm in small hill watershed area in Center China, was studied, after the systematical analyses with its system dynamic digraph, three common management policies are presented at the end of the paper.     

畜禽排泄物对环境的危害及处理进展

随着畜牧业的飞速发展,生产规模的扩大和集约化程度的提高,畜禽排泄物已成为重要的环境污染源之一。解决畜禽排泄物对环境的污染问题,也是保护生态环境的一项重要内容。作者对畜禽排泄物的危害、处理现状及无害化处理方式进行了讨论,认为利用畜禽粪便进行资源化有效利用、大力发展有机肥产业是解决大中型养殖企业产生的大量畜禽排泄物的有效途径,是实现畜牧业可持续发展的必由之路。     

The concentration of ammonia in the excreta of sixth instar larvae ofLamida moncusalis Walker (Pyralidae: Lepidoptera) during development

Summary The concentration of ammonia in the fresh and dry excreta ofLamida moncusalis Walker was determined. It was found that a large quantity of ammonia was lost from the excreta on drying. Ammonia is one of the major excretory products of the larva.5 September 1986Acknowledgment. We thank the State Committee on Science, Technology and Environment, Kerala, for the financial assistance.