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981.
抽水蓄能电站运行及检修期间存在大量高处作业,而通过技术改造进行高坠防护,既增加电站运营成本,同时也给运行及检修造成一定影响。为此,通过对已投入运行和正在建设的抽水蓄能电站存在的高处作业情况的调研与分析,围绕施工期高坠风险控制,系统研究抽水蓄能电站运行及检修作业防高坠设施的设置技术与方法,最终编制《抽水蓄能电站防高坠安全防护设施设置图集》和《抽水蓄能电站防高坠安全防护设施设计报告》,研究成果可用于指导新建电站工程建设和已建电厂的相关技术改造。  相似文献   
982.
The EU vision of sustainable agriculture, land use, forestry and management of natural resources contributes to the balanced exploitation of the environment, taking into account rural development strategy. Whilst the EU directs activities through legislative tools, national systems of public administration are responsible for the implementation of the respective laws. Despite there not being acquis communautaire in public administration, non-formal cooperation has nevertheless emerged and systems of national public administration have to meet EU criteria and ensure the effective implementation of legislation. The paper presents an analysis of how Slovak state administration has converged with EU requirements in the field of sustainable agriculture, land use, forestry and natural resources. Administrative convergence is considered through the internal convergence represented by capacities without legal subjectivity, and through external convergence represented by legal and administrative subjectivity. Both approaches are observed at the central level within specialized public authorities. Local state administration is characterized by the creation of internal administrative capacities with the challenging delimitation of which competences are affected by the process of administrative convergence.  相似文献   
983.
洞庭湖区农业环境与湖垸农业可持续发展模式   总被引:9,自引:1,他引:8  
围湖垦殖形成了洞庭湖区湖垸农业形式,湖垸农业的形成加速了湖区人口的增长,人口的压力也促进了围垦。不断的围湖垦殖使耕地面积迅速增加。由于湖泊面积减少,湖垸农业处于外洪内涝的环境中。归纳了洞庭湖区的农业环境问题:洪涝灾害发生频率加大;水面减少,生物多样性降低;环境污染严重,湿地生态功能衰退;土壤退化和潜育化严重;血吸虫病死灰复燃等。结合已有经验,提出了湖垸农业可持续发展模式:认真实施生态保护工程,减少泥沙淤积;调整湖垸农业结构,建立可持续发展生态农业模式:避灾、减灾模式、水生经济植物模式、工业原料作物模式、林农复合经营模式、湖洲草地草食畜禽模式、麻基(油菜)渔塘农业模式等。  相似文献   
984.
Soil loss, nutrient depletion and land degradation contribute to the skimpy performance of smallholder agriculture and pose serious policy challenges in developing countries. Surprisingly, natural resource management practices that enhance sustainability while improving productivity have not been fully adopted despite continuous efforts of promotion. Using data collected from 2901 farm households in the Farmers Innovation Fund (FIF) of the World Bank, this study examines factors delaying adoption of resource management and farming practices from the perspective of social learning and network size. Specifically, the study aims at identifying the extent to which differences in network structure matter in providing opportunities to learn about new ways of sustainable resource management practices using regression analysis. The result confirms that social network size plays a significant role in enhancing adoption of natural resource management practices. Moreover, external sources of information such as extension provision play a crucial role in enhancing adoption of resource management practices. Thus, future endeavours should link extension services to informal networks to enhance adoption of sustainable natural resource management practices.  相似文献   
985.
SUMMARY

Over-population in relation to poor land productivity and cultivation in less fertile lands is resulting in land degradation and deforestation in UP hills. Growing demand of more food production and increasing need for more cash in hand have forced the hill people to cultivate all kinds of land, resulting in the denudation of land resources and soil erosion. These changes resulted in out migration of the area's human resource. A new management system for the revival of natural resources and the sustainable utilization of the area's human population and livestock has been proposed, involving active local participation in order to change the existing land-use to a system based on the soil fertility scale.  相似文献   
986.
Although sustainable development has already been promulgated as one of its fundamental strategies by the national government since 1993, sustainable development, as an exotic new paradigm characteristic of profound philosophical and ethical thinking initiated in developed countries, is still not familiar to the Chinese people. Fortunately, in parallel to the evolution of sustainable agriculture, mainly in developed countries, since the beginning of the 1980s, Chinese agricultural scientists and technicians have already innovated their own unique form of Chinese Ecological Agriculture (CEA), on the basis of traditional agriculture that has been sustained for more than 4000 years. The basic principle of CEA emphasizes the obeying of both ecological rules and economic rules, as well as the approach of systematics and ecological engineering exactly corresponding to those adopted by sustainable development. The major difference between the two is that CEA has already been executed on a very large scale and has served as an effective and popularized way to implement sustainable agriculture in most parts of China. Also, as an active way of intensifying agriculture in terms of more inputs of skills, knowledge and labour, CEA is contributing much to all-round rural development throughout China.  相似文献   
987.
During the process of urbanization, people are subject to the indiscriminate use of resources due to competition. The present trend in global population growth predicts that the situation will be aggravated as many people prefer living in towns and cities to resource-poor rural areas. In consequence, limited space, high percentage of ageing population, urban poverty, environmental pollution, changes in urban lifestyles and varied consumption patterns have to be dealt with in sustainable development strategies. In this context, urban agriculture can play a vital role by visualizing the urban homestead as a potentially viable production unit of agriculture. In order to live with limited urban infrastructure facilities, environmental conditions and socio-economic situations, the concept of the Family Business Garden justifies the necessity of its presence through the experience in the Western Province of Sri Lanka. Having a proper mix of environmental and commercial agricultural concerns, the concept paves the way not only to address family food requirements but also to produce for markets under liberalized economies by promoting agro-entrepreneurship and social capital development attempts in urban communities.  相似文献   
988.
控制和削减农业污染物排放总量是国家环境保护"十二五"规划的重点工作之一,但现行的环境管理及产排污量削减与控制技术中还没有完整的农业污染减排的指标体系。该文阐述了构建农业污染减排指标体系的基本原则和方法,综合考虑不同农业生产类型污染物产排过程的特点,从种植业、畜禽养殖业和水产养殖业3个方面初步构建农业污染减排指标体系,以期为研究农业主要污染物减排核算体系的关键参数和制定减排核算技术方法提供基础性技术支持。基于当前农业污染减排实施中可能存在的问题,对指标体系的进一步完善提出了相关建议。  相似文献   
989.
为探讨深圳市农林土壤重金属的污染现状,系统采集了深圳市菜地、果园、林地和荒地4种土地利用的52个土壤样品,测定了Cu、Pb、Cd、Zn、Cr、Ni6种重金属的全量,对深圳市农林土壤重金属20余年来的累积状况进行了分析并进行了初步的风险评价.结果发现,深圳农林土壤均存在不同程度的重金属累积,总体而言,Cu、Pb、Zn、Cr和Ni的累积较轻,Zn的最大含量尚未超过其80年代末背景值的最大值;Cd的累积最为严重,其最大含量已为背景最大值的16倍.以GB15618-1995为标准,对深圳农林土壤的重金属风险进行评价后发现,Cu的污染最轻,仅20%的菜地土壤超过国家一级标准,Pb50%超过国家一级标准,但尚未超过二级标准;Zn、Cr和Ni均有一定比例的样点超过二级标准,最少4%,最高50%,但未有超过三级标准的样点;Cd的风险最大,不仅有大量超过一、二级标准的样点,而且超过三级标准的样点也占有一定的比例(菜地、果园、林地和荒地土壤中Cd含量超过三级标准的比例分别为10%、23%、29%和50%).深圳农林土壤中的Cd污染应该引起相关部门的重视.  相似文献   
990.
北京市典型有机设施蔬菜基地重金属污染特征及风险评估   总被引:1,自引:0,他引:1  
为研究北京市典型有机设施蔬菜基地重金属污染状况,采用野外调查及室内分析法,选取北京市5个有机设施蔬菜基地中125个土壤样品和77个蔬菜样品进行了Pb、Cd、Cr、As和Hg含量的检测、统计分析与评价,对土壤重金属含量与土壤理化指标进行了相关分析,研究了重金属在蔬菜中的迁移规律,并结合美国环保署(US EPA)推荐采用的健康风险评价模型,评价由于蔬菜摄入导致的成人和儿童的健康风险。结果表明,5个设施蔬菜基地中有极少数土壤样本Cd含量超标,有极少数叶菜样本Cr含量超标,其他重金属含量均未超标。污染指数评价表明5个基地土壤重金属污染排序为:基地5基地1基地3基地2基地4,主要由土壤Cd累积所致。土壤重金属与理化性质相关性表明,5种重金属含量都受土壤的理化性质影响较大。总体上,5种重金属在土壤-蔬菜中迁移能力排序为:CdHgAsCrPb,在不同类蔬菜中的富集系数排序为:叶菜类茄果类瓜果类豆菜类。5种重金属造成的目标危害系数大小依次为:CdPbAsHgCr,不同类蔬菜的综合重金属目标危害系数值排序为:叶菜类茄果类瓜果类豆菜类,所有蔬菜单一重金属目标危害系数和复合危害系数都远小于1,说明单一重金属和复合重金属污染对成人和儿童都没有明显的负面健康影响。  相似文献   
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