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Rajiv K. Sinha Sunil Herat Sunita Agarwal Ravi Asadi Emilio Carretero 《The Environmentalist》2002,22(3):261-268
The practice of vermiculture is at least a century old but it is now being revived worldwide with diverse ecological objectives such as waste management, soil detoxification and regeneration and sustainable agriculture. Earthworms act in the soil as aerators, grinders, crushers, chemical degraders and biological stimulators. They secrete enzymes, proteases, lipases, amylases, cellulases and chitinases which bring about rapid biochemical conversion of the cellulosic and the proteinaceous materials in the variety of organic wastes which originate from homes, gardens, dairies and farms. The process is odour free because earthworms release coelomic fluids in the decaying waste biomass which has anti-bacterial properties which kills pathogens. The species used in India were Indian blue (Perionyx excavatus), African night crawler (Eudrilus euginae) and the Tiger worm (Elsinia foetida). E. foetida was used in Australia. E. euginae was found to have higher feeding, growth and biodegradation capacity compared to other two species.Earthworm action was shown to enhance natural biodegradation and decomposition of wastes (60–80 percent under optimum conditions), thus significantly reducing the composting time by several weeks. Within 5 to 6 weeks, 95–100 percent degradation of all cellulosic materials was achieved. Even hard fruit and egg shells and bones can be degraded, although these may take longer. 相似文献
234.
城市生活垃圾综合处理前分选系统设计 总被引:2,自引:0,他引:2
本文以江油市城市生活垃圾处理厂为工程实例,介绍了垃圾前分选系统中的垃圾储料车间、行车与抓斗、垃圾上料机构、双层振动筛以及人工分选平台的工艺设计参数及设计依据,并在此基础上提出了该系统的改进建议. 相似文献
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Joseph L. Pavoni D. Joseph Hagerty Robert E. Lee 《Journal of the American Water Resources Association》1972,8(6):1091-1107
Since the publication of Rachel Carson's Silent Spring in 1962 there has been a rapidly growing public concern over widespread contamination of the environment with hazardous wastes. In recent years scientific findings on the ecological effects of various hazardous substances have posed several important questions. What exactly are hazardous wastes? Can these substances be disposed of in a technically feasible, economical, and safe way with assurance that they have been permanently eliminated from the ecosystem? What compositional alterations or movements of the hazardous wastes occur in water, soil, or air systems? What effect will these wastes have on the water, soil, or air systems? What effect will these wastes have on the water, soil, or air properties? Consequently, a University of Louisville study has developed a relevant definition of hazardous wastes for the Environmental Engineering profession together with priority of concern rating systems to delineate the degree of environmental impact imposed on a total ecosystem by a hazardous waste and the feasibility of disposing of hazardous substances at specific landfill sites. It is felt that refinements of the priority of concern rating systems offered here may provide a sound basis from which procedural decisions may be structured to establish future national hazardous waste disposal sites. 相似文献
237.
刘向葵 《中国环境管理干部学院学报》1999,(4)
用城市生活垃圾经好氧高温制成堆肥,并向其中加入无机化肥和微量元素添加剂可制成有机复合肥。本文简要阐述了好氧高温堆肥的生产工艺,推荐了用垃圾生产有机复合肥的两类配方。 相似文献
238.
百口泉地下水电导率与溶解性总固体相关性讨论 总被引:3,自引:0,他引:3
由于溶解性总固体的测定较为复杂,平行性、稳定性差,而电导率的测定简便、迅速,重现性、稳定性好,若二者相关关系显著,可通过测定电导率,按一定的比例推算水中溶解性总固体的量。通过对百口泉地下水的溶解性总固体与电导率的相关性的监测、分析,经统计检验,线性关系显著,其比值范围在065~076,均值为07,即百口泉地下水的电导率1μs/cm相当于070mg/L的溶解性总固体。 相似文献
239.
宝贡敏 《中国人口.资源与环境》1994,4(1):76-79
我国乡镇工业企业的发展与环境、资源的协调问题已经成为我国发展与环境、资源关系方面的大问题。实行工农相对分离,组建乡村工业区,是提高乡镇工业企业素质、效益,强化乡镇工业企业优化组合、规模经营的有效途径;是保护环境,实现资源有效利用的基础工作之一;是提高农业劳动生产率,实现农业规模经营的基础工作之一。 相似文献
240.
The composting potential of different organic solid wastes: experience from the island of Crete 总被引:4,自引:0,他引:4
Manios T 《Environment international》2004,29(8):1079-1089
For the past 20 years, the National Foundation for Agricultural Research in Crete and the School of Agricultural Technology of the Technological and Educational Institute of Crete have been involved in a number of research and development activities, related to the production and evaluation of compost derived from a variety of local solid, mainly agricultural organic wastes. Materials such as olive press cake, olive tree leaves (OTL) and branches, vine branches (VB), pressed grape skins (PGS), pig manure (PM), sewage sludge and the organic fraction of municipal solid waste (OFMSW) have been evaluated for their behaviour during composting, their compatibility in mixtures and the quality of the end product. The quality evaluation included both a detailed physiochemical (pH, electrical conductivity (EC), nutrients concentration, heavy metal concentration, etc.) and biological analyses (pathogenic microorganisms). It also included an agronomic evaluation, in which composts were used either as a soil amendment or as a component for substrates in open air or covered (greenhouse) cultivation mainly of local vegetables (tomatoes, cucumbers, etc.). All materials were composted successfully, especially when mixed. The end products contained large amounts of organic matter, usually combined with an increased EC value. Pressed grape skins should be considered as the ideal raw material, producing a high quality compost, with the lowest EC value (1.57 mS cm(-1)) and the largest organic matter concentration (84.50%), compared to all other materials. When any of the produced compost was used in a ratio of 30% by volume (v/v), it increased plant growth, whereas in larger volumes, it presented phytotoxic behaviour, inhibiting both root and shoot development. 相似文献