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排序方式: 共有3541条查询结果,搜索用时 15 毫秒
941.
The use of computer-assisted map analysis techniques for prediction of storm runoff from a small urban watershed in the United States is investigated. An automated procedure for calculating input parameters for the US Soil Conservation Service (SCS) method of predicting storm runoff volume and peak timing is presented. Advanced techniques of spatial analysis are used to characterize spatial coincidence, surface configuration and effective hydrologic distance. A limited verification of the automated procedure indicates that the model reasonably characterizes water flow. A sensitivity analysis of basin disaggregation suggests that the SCS method yields increased volume and peak discharge predictions as the watershed is divided into smaller and smaller subunits. As a means to demonstrate the practical application of the automated procedure, a simulation of the effects on surface runoff for a potential residential development is presented. 相似文献
942.
943.
Bruce K. Ferguson 《Journal of the American Water Resources Association》1987,23(1):147-152
ABSTRACT: The increasing use of irrigation for urban landscapes is causing new demands for efficient watering systems. Conservation techniques for irrigated agricultural fields cannot be applied to urban landscapes without amendment. This paper attempts to review methods of urban landscape water conservation in the context of the diversity and complexity of urban landscapes and the demands upon them for quality of the urban environment. A development's initial site layout and planting design fundamentally determine how much irrigation water will be required; the complexity and creativity inherent in urban design open a number of specific possibilities for reducing water demand. Irrigation hardware is then designed to deliver the required volume of water to the specified landscape efficiently by implementing a number of physical and operational principles. Maintenance of the finished development involves monitoring results and making adjustments as the plantings grow and develop. The potential for conserving urban irrigation water is large. Effective conservation need not compromise other qualities of the urban environment such as aesthetics, screening, or shade. Urban design can address both the kinds of landscapes people need, and minimal consumption of irrigation water. 相似文献
944.
Laszlo Farago 《Journal of Environmental Planning and Management》1988,31(2):83-88
The author provides an account of Hungarian regional policy and planning during the last 40 years, describing a socialist state trying to escape from a centrally planned economy. The paper discusses the consequences of the reforms and the problems of conflict resolution which resulted. The author argues that central planning will continue to be necessary in the future, and that there is a need to strengthen the co‐ordinative role of regional plans. 相似文献
945.
Roger Smith 《Journal of Environmental Planning and Management》1984,27(1):18-22
The British Ecological Society has suggested that computer‐based techniques could be used in the coordination of policies across different land uses in upland planning. This paper looks briefly at one such technique — a linear programming model — and describes its use at a regional scale for the Sedburgh area in north‐west England. The paper concludes with consideration of why such models are not in more common use. 相似文献
946.
Ian Brotherton 《Journal of Environmental Planning and Management》1984,27(2):92-97
The Countryside Commission's report, “A Better Future for the Uplands”, contains recommendations that seek a better balance between conservation and farming and conservation and forestry: recommendations that concern the uplands as landscape. This paper considers the recommendations under three headings — those which seek to reduce conflict, those which seek to reinforce the voluntary approach to conflict resolution, and those which seek to extend control. The paper concludes with a consideration of the likely effectiveness of the measures proposed. 相似文献
947.
Jonathan D. Phillips 《Journal of the American Water Resources Association》1984,20(6):847-850
In areas where there is little or no topographic relief and where soils, vegetation, geologic structure and other factors are essentially uniform, identification of drainage basin boundaries is difficult or impossible. In such a homogeneous landscape, however, assumptions may be made that the hydrologic and geomorphic controls over drainage basin development are constant within the area. If this is true, it is suggested, the drainage area of a stream is related solely to the stream length and factors governing the length-area relationship are also constant. A simple formula based on these assumptions and the gravity model is proposed which can be used to estimate drainage divides in a homogeneous landscape. 相似文献
948.
Patricia Bobrow Barbara Gaige Glenn Harris Joyce Kennedy Leslie King William Raymond Darrin Werbitsky 《Environmental management》1984,8(1):45-53
This study compares the effectiveness of two regional planning agencies in terms of public support for various planning activities. The Adirondack Park Agency and the Temporary State Commission on Tug Hill have fundamentally different approaches to planning. The Adirondack Park Agency has implemented a restrictive regulatory program with little citizen participation by Adirondack residents. The Tug Hill Commission has implemented an advisory and coordinating program with an emphasis on public input. Residents of two towns in each region were surveyed to determine environmental concern and support for regional planning activities. Respondents from both regions favored a planning agency that incorporates citizen input; controls air, water, and toxic waste pollution; and develops recreation areas. They strongly opposed an agency that regulates private land-use. Basic demographic characteristics and levels of environmental concern were similar in all four towns, but receptivity to various planning activities was consistently greater among residents of the Tug Hill Region. Paired comparisons of the four towns demonstrated no differences between towns of the same region and significant differences between towns of different regions. Public support for regional planning is greater in the Tug Hill Region than in the Adirondack Park. 相似文献
949.
利用 1 988— 2 0 0 0年新疆塔里木河下游TM影像解译的土地覆盖 (土地利用图 )和景观多样性指数、斑块重要值、破碎度、分维数等景观生态学指标 ,进行了塔里木河下游土地利用格局的空间分布和时间动态分析。 相似文献
950.
LANDSCAPE DEVELOPMENT INTENSITY INDEX 总被引:12,自引:0,他引:12