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51.
52.
粉煤灰场复垦地肥力状况及对土壤理化性质的影响 总被引:1,自引:0,他引:1
选择安徽省淮南市上窑镇粉煤灰处置场覆土复垦地为研究区域,测定覆土厚度和土壤剖面各层的容重、pH、含水量、有机质等理化性质,土壤总氮、有效磷、速效钾等养分含量,以及冬小麦抽穗期的生物量,研究粉煤灰处置场复垦土壤理化性质及其与土壤养分的相关性,不同覆土厚度复垦地冬小麦生长的差异性.结果表明,粉煤灰场复垦地土壤总氮含量约0.90 g/kg,有效磷和速效钾含量分别为12~76 mg/kg、114~135 mg/kg,土壤肥力与作物生长状况和自然农业土壤相比差异不显著;除复垦土壤厚度、容重、含水量对有效磷含量影响显著外,其余土壤养分与土壤理化性质和表土厚度的相关性不强. 相似文献
53.
阿拉腾格日勒 《畜牧兽医科学(电子版)》2021,(5):173-174
畜牧作为推动农业发展的动力,可促进其发展现代化农业,提高农民收入。但是,随着畜牧业发展,加剧粪污污染问题,应加强粪污处理及资源化利用,以达到保护环境的目的。该文主要从畜禽粪污处理和资源化利用重要性切入,分析目前粪污处理与资源化利用方式,提出相应保障措施,进而推动畜牧业实现绿色发展。 相似文献
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本文以我国农村污水的特征与主要成分分析为切入点,简要地介绍了现今农村污水生态治理的应用现状和存在的问题,并以生态复合型湿地为研究对象,从湿地填料、湿地植物、湿地微生物等方面对其性能优化进行了较为详尽的论述。 相似文献
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病死畜禽无害化处理工作事关养殖业安全、公共卫生安全和生态环境安全。河南省2013年实施病死畜禽无害化集中处理体系建设以来,已建成病死畜禽无害化集中处理场100个,日均处理能力1350t,病死畜禽收集点1990个,在政策扶持、机制创新、资金支持、执法监督等方面积累了丰富经验,创设了病死猪无害化处理与保险勘查理赔相挂钩的联动机制——“河南模式”,但也存在体系规划不合理、建设标准不高、政策不完善等问题。本文结合实际,提出制定法律法规、完善扶持政策、加强科技研发、加强宣传引导等建议,以期为深入推进病死畜禽无害化集中处理体系建设提供借鉴。 相似文献
58.
Eradication of H5 and H7 influenza in a positive flock will include mass depopulation of birds, containment and inactivation of the virus in the carcasses and litter, and decontamination of the facility. A quick response is desired in the event of a disease outbreak. Ideally, birds should be depopulated within 24 h after detecting the virus. Mass depopulation of birds must be performed in a humane manner while minimizing human health and biosecurity risks. In the framework of the European legislation, a number of methods are authorized for the killing of poultry for processing prior to marketing. However, during emergencies such as a disease outbreak, there are fewer options. The current most commonly used procedures for large-scale emergency depopulation of birds consist of exposing poultry to CO or CO(2) gas. Both gasses have been used in Belgium during the H7N7 crisis in 2003. The gassing procedures include whole house gassing, portable panel enclosures, cage cabinets, containers and polyethylene tent method. Whole house gassing requires sealing the house to prevent gas leakage and, using specialized equipment, introducing large volumes of gas evenly over the birds. All procedures are very labour intensive, create a biosecurity risk and require a large number of personnel. There are considerable region-to-region differences in emergency depopulation techniques and disposal of carcasses and infected material. Because of the differences in bird type and species, management, housing and stocking density, it is difficult to propose a depopulation technique that will be suitable for all circumstances. Safety of the human operators is an increasing concern with all H5 and H7 strains and in particular with the highly pathogenic H5N1 strain. Researchers and commercial poultry companies in the United States recently established that non-toxic water-based foam with a certain bubble size presents a practicable, effective and humane method for mass depopulation. Foam of the right bubble size creates an occlusion in the trachea of birds, causing a rapid onset of hypoxia. The foam that blankets the broiler house induces physical hypoxia - the same cause of death as the approved method using carbon dioxide gas (CO(2)). The article illustrates the different culling and disposal methods with a focus on the methods used during the 2003 H7N7 crisis in Belgium. 相似文献
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Long-term effects of farmyard manure and sewage sludge on some soil biochemical characteristics 总被引:2,自引:0,他引:2
A. Saviozzi A. Biasci R. Riffaldi R. Levi-Minzi 《Biology and Fertility of Soils》1999,30(1-2):100-106
Changes in some soil biochemical properties were investigated following repeated applications of aerobically digested sewage
sludge (SS) under field conditions over 12 years, and compared with those of an adjacent soil cultivated and amended with
5 t ha–1 year–1 (dry weight) farmyard manure (FYM) for at least 40 years, as well as with those of an adjacent uncultivated soil, in order
to ascertain changes in soil quality. A short-term aerobic incubation was used to determine the potential of the samples to
mineralize the organic C supplied. Results indicated that cultivation caused a reduction in total, humified and potentially
mineralizable organic C, total N, light-fraction (LF) C, total and water-soluble carbohydrates, phenolic compounds, cation-exchange
capacity (CEC), microbial biomass C, specific respiration, hydrolytic and urease activities, and an increase in the heavy
metal content. Total and water-soluble carbohydrates and phenolic compounds expressed as a percentage of total organic C (TOC)
were similar in the differently managed plots. Of the two amendments, FYM treatments showed higher amounts of TOC and N, LF-C,
total and water-soluble carbohydrates, phenolic substances, CEC, specific respiration of biomass, hydrolytic and urease activities,
similar amounts and characteristics of humified organic matter and lower concentrations of Cu, Zn and Cr. Both FYM and SS
were inadequate treatments for the restoration of soil organic matter lost as a consequence of cultivation.
Received: 20 October 1998 相似文献