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951.
Hugh Begg Greg Lloyd David Newlands 《Journal of Environmental Planning and Management》1989,32(2):101-105
This article discusses the structure and performance of Work‐Start Ltd., a company located in Dundee and providing training for the unemployed. The company has attracted national and international attention by its innovative approach. Set up to meet the specific problems of peripheral housing estates, it is now responding to rapid changes in the local labour market. 相似文献
952.
A. Parviz Koohafkan 《Natural resources forum》2000,24(2):69-81
Land degradation continues to be a major threat to local and national food security. With limited potential to develop new land, any increase in agricultural production must be sought largely through the better use of land already under cultivation. Concerns for the global environment associated with agriculture worldwide have also increased in recent years and require more coordinated efforts at global and national levels with decentralisation of activities at the local level.
This article presents an overview of land resources potential for food production, the processes and extent of land degradation and its economic and environmental costs and impacts, and highlights some macro-economic policies and institutional measures for the prevention of land degradation and rehabilitation of degraded lands. A people-centred programme is presented as a basis for decentralising activities for sustainable land use and land management. Finally, the need for better coordinated efforts of concerned UN, multinational agencies and NGOs for the implementation of Agenda 21 and related conventions is stressed. 相似文献
This article presents an overview of land resources potential for food production, the processes and extent of land degradation and its economic and environmental costs and impacts, and highlights some macro-economic policies and institutional measures for the prevention of land degradation and rehabilitation of degraded lands. A people-centred programme is presented as a basis for decentralising activities for sustainable land use and land management. Finally, the need for better coordinated efforts of concerned UN, multinational agencies and NGOs for the implementation of Agenda 21 and related conventions is stressed. 相似文献
953.
Management of riparian habitats has been recognized for its importance in reducing instream effects of agricultural nonpoint
source pollution. By serving as a buffer, well structured riparian habitats can reduce nonpoint source impacts by filtering
surface runoff from field to stream. A system has been developed where key characteristics of riparian habitat, vegetation
type, height, width, riparian and shoreline bank slope, and land use are classified as discrete categorical units. This classification
system recognizes seven riparian vegetation types, which are determined by dominant plant type. Riparian and shoreline bank
slope, in addition to riparian width and height, each consist of five categories. Classification by discrete units allows
for ready digitizing of information for production of spatial maps using a geographic information system (GIS). The classification
system was tested for field efficiency on Tom Beall Creek watershed, an agriculturally impacted third-order stream in the
Clearwater River drainage, Nez Perce County, Idaho, USA. The classification system was simple to use during field applications
and provided a good inventory of riparian habitat. After successful field tests, spatial maps were produced for each component
using the Professional Map Analysis Package (pMAP), a GIS program. With pMAP, a map describing general riparian habitat condition
was produced by combining the maps of components of riparian habitat, and the condition map was integrated with a map of soil
erosion potential in order to determine areas along the stream that are susceptible to nonpoint source pollution inputs. Integration
of spatial maps of riparian classification and watershed characteristics has great potential as a tool for aiding in making
management decisions for mitigating off-site impacts of agricultural nonpoint source pollution. 相似文献
954.
955.
引入环境参数、社会综合参数、行业参数,根据企业实际排污情况,探讨了运用污染指数法对污染企业实行定量化管理的方法。 相似文献
956.
文中通过对涵养水源功能分级和自然植被第一性生产力计算,评价自然植被生态承载力;通过水资源总量、用水预测确定供需平衡关系及因素,给出该保护区生态功能承载力结论。 相似文献
957.
958.
简要介绍带式运输机防尘装置的研究设计和工程应用情况。实际应用结果表明 ,该装置能长期有效地控制带式运输机尘源 ,便于工人操作和维护检修 ,并可使排风量平均降低 5 0 %以上 ,大大节省了一次投资、运行费和维护管理费 ,是一项值得推广的实用技术 相似文献
959.
上海市郊4种地表径流深度的测算 总被引:7,自引:0,他引:7
根据有关试验资料和美国土壤保持局推荐的方法,提出了上海市郊4种地表径流深度的计算公式。计算结果表明,当年降雨量为1053mm时,上海市郊4种地表径流的总量为13.6亿m^3,平均径流深度为300mm,径流系数为28.49%,4种径流量占郊区总量的77.82%,产流面积为郊区总面积的75.10%。 相似文献
960.
上海市郊主要的非点源污染及防治对策 总被引:25,自引:1,他引:25
据1995年完成的上海市郊非点源污染现状的调查材料表明,上海市郊主要的点源污染有:畜禽粪尿,农药:化肥和生活污染等几方面,该文指出了上海市郊非点源污染较严重,防治非点源污染是上海环保工作的重要组成部分,并进而提出了防治非点源污染的一些体具体对策和措施。 相似文献