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991.
ABSTRACT Environmental resources can be managed properly only by adopting a comprehensive approach. The whole environment must be considered as a single system, and prior to any action, all types of environmental impacts caused by it should be studied in detail. This paper underlines the close relationship between different environmental problems, analyzes existing management patterns, and proposes new alternatives whenever applicable. The different constraints, which have to be considered in the decision-making process while developing a plan, are also discussed. It is concluded that efforts neglecting the interaction among different aspects of the environment do not upgrade the quality of water, air, and land to any appreciable degree.  相似文献   
992.
ABSTRACT. An ever increasing number of communities throughout the nation are being forced by Federal legislation and local pressures to adopt land use and control measures related to drainage and flood protection. In many instances communities are hastily adopting ordinances and regulations which later prove difficult to administer and enforce. In addition, many of these ordinances and regulations are not producing the results originally anticipated. This paper discusses the basic elements of a drainage ordinance and evaluates the role of the ordinance in a comprehensive drainage program. This evaluation is based on the results of a two year study of drainage programs in five urban areas which produced a model urban drainage ordinance and recommendations on the administration of the ordinance. Personal interviews and local documents are used as the data base in formulating conclusions and recommendations.  相似文献   
993.
A three-tiered structure of land-use and environmental management is here proposed for Australia. The structure is based on the idea that environment means the environment of people, and that environmental problems arise when a change in the interaction between people and their environment leads to conflicts about the use of land and resources. The heterogeneity of society means that a range of human aspirations and value systems must be satisfied by environmental managers. Existing methods of environmental management fail to achieve these objectives, due to inadequate perception of environmental problems by decision-makers, and the inability of currently available impact assessment techniques to resolve human conflicts associated with the use of land and resources. The main work of planning and managing land use and the environment would be carried out by regional authorities, supported by federal and state policy. Examples are given of moves towards regional administration in England and Wales, Western Australia, Australia and New Zealand. Community participation in the decision-making process is essential and can be achieved by electoral representation to the authoritative bodies and through procedures that ensure informed public comment on planning proposals.  相似文献   
994.
ABSTRACT: ERTS-1 satellite imagery has been evaluated as a means of providing useful watershed physiography information. From these data physiographic parameters such as drainage basin area and shape, drainage density, stream length and sinuosity, and the percentage of a watershed occupied by major land use types were obtained in three study areas. The study areas were: (1) Southwestern Wisconsin; (2) Eastern Colorado; and (3) portions of the Middle Atlantic States Using ERTS-1 imagery at 1:250,000 and 1:100,000 scales it was found that drainage basin area and shape and stream sinuosity were comparable (within 10%) in all study areas to physiographic measurements derived from conventional topographic maps at the same scales Land use information can be usefully extracted for watersheds as small as 30 mi2(78 km2) in area. Improved drainage network and density information is obtained from ERTS-1 imagery in dissected areas such as Southwestern Wisconsin, but in heavily vegetated areas (Middle Atlantic States) or areas with little physical relief (Eastern Colorado) low order streams are difficult to detect and the derived drainage densities are significantly smaller than those obtained from standard maps. It is concluded that ERTS-1 imagery can be employed to advantage in mean annual runoff prediction techniques and in providing or maintaining land use information used in the calibration and operation of watershed models.  相似文献   
995.
ABSTRACT. The Nation has entered a new era of water quality management in which land use policy and regulation must assume an increasingly important role. The benefits of tertiary and advanced waste treatment may be offset by contradictory land use and pollution from land runoff. Unless land use planning and controls are included in water quality management, land-imposed constraints on water quality can be anticipated. Pollution from major types of land runoff are reviewed with respect to sources, effects, and control procedures. Emphasis is given to land use practices and controls. The crucial issue with regard to the latter is lack of land use policies at federal, state, and local levels. State legislation establishing guidelines and minimum standards for land use regulation by local government is required. The dependency of water quality on land use points to the fallacy of attempting to provide for comprehensive water pollution control outside the context of comprehensive land-water resource planning and management.  相似文献   
996.
Monitoring Parks Through Remote Sensing: Studies in Nepal and Honduras   总被引:3,自引:0,他引:3  
The effectiveness of parks as management regimes is hotly contested. Much of the current discussion centered around comparisons of management regimes can be traced to a dearth of cross-site quantitative evaluations. Remote sensing provides a particularly effective tool for this purpose, yet analysis of remotely sensed data requires fieldwork to interpret human activities and the socioeconomic and political contexts that relate to land cover change. This paper examines the effect of establishment of the Celaque National Park, Honduras, and the Royal Chitwan National Park buffer zone, Nepal, on limiting deforestation. In Celaque, the park itself has been largely successful in maintaining forest cover. However, recent changes in land use patterns have led to increasing pressure on the park boundaries, exacerbated by the lack of involvement of local residents. In the Royal Chitwan National Park, in contrast, participatory approaches towards co-management have been implemented over the past decade in the park buffer zone. With significant incomes derived from ecotourism, complete protection of the buffer zone forest has been adopted, leading to significant regrowth of tree cover. However, local decision-making power is limited, and buffer zone management has largely proven successful due to the investment and support provided by international donor agencies. These two case studies demonstrate the utility of remote sensing and Geographical Information Systems analysis in providing a spatiotemporal perspective for assessing management policies. They also demonstrate the importance of fieldwork to provide a nuanced understanding of the socioeconomic and institutional conditions affecting the outcomes of forest management regimes.  相似文献   
997.
马尔柯夫法在耕地质量动态评价中的应用   总被引:6,自引:0,他引:6  
根据随机过程原理,构建了新的转移矩阵,建立了一个马尔柯夫链综合耕地质量评价模型.通过实例的应用,分析证明了其模型的可靠性,从而为耕地质量动态评价的科学化提供了依据.  相似文献   
998.
梁栋栋  陆林 《资源开发与市场》2004,20(3):211-212,215
通过对贫困地区旅游开发过程中土地利用变化的分析,提出了土地利用变化的驱动力和评价原则,并根据旅游地生命周期理论,对未来土地利用的趋势和方向进行了分析,同时指出在开发旅游时应注意的问题.以安徽省舒城县百丈岩旅游区为例,在分析旅游开发可行性的基础上提出了本区的旅游发展战略,最后分析了旅游开发对土地利用结构变化的影响.  相似文献   
999.
淮北市采煤塌陷区的土地复垦   总被引:4,自引:0,他引:4  
安徽省淮北市的淮北矿区是我国重要的十大煤炭生产基地之一,现有大小煤矿30余座.长期以来,因采煤而造成的塌陷土地累计达14667hm2,由此引起的地貌变形、房屋倒塌、生态环境恶化等灾害,严重影响了当地工农业生产和人们的生活.因此,加强对采煤塌陷区土地复垦的研究极为重要.在实地考察和有关数据分析的基础上,将淮北矿区因采煤塌陷而被破坏的土地分为四个区,总结出两大土地复垦模式,并对复垦后的土地利用进行适宜性评价.  相似文献   
1000.
贵州省黔南州耕地保有量研究   总被引:13,自引:0,他引:13  
根据2001~2010年土地开发复垦规划、建设项目用地、生态退耕等预测,分析了1997~2010年土地利用总体规划存在问题,提出了黔南州下一轮修编土地利用总体规划应达到的耕地保有量.  相似文献   
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