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91.
92.
贵州省自然灾害区域分异规律及分析方法研究 总被引:2,自引:0,他引:2
贵州省自然灾害严重,且种类多,区域差异明显。为了分析自然灾害区域分异规律,本文提出了灾害模数、灾害区域差异系数等概念,编制了贵州省灾害等级图。 相似文献
93.
A method is described for the rapid survey and determination of the ecological value of woodlots. The three dominant tree species in a stand are given a visual ranking that is converted to awoodlot index through the use of species adaptation values. The woodlot index is scaled by presettlement vegetation type to yield awoodlot scale. The ecologically most valuable woodlots in a region are identified by using the woodlot scale and data on woodlot area, human disturbance, and tree density. The woodlot index corresponds closely to results from conventional methods of woodlot surveys. This method should be valuable to land-use planners for environmental impact assessment and regional planning. 相似文献
94.
A series of studies examined the effects of labelled meaning on affective response to housing scenes. Students at Ohio State University assessed their feelings towards imagined housing (public or private) and cities (Memphis, Houston and San Francisco). Expected differences in the affective quality were found. Responses to color photographs of specific housing scenes labelled as either private condominiums or public housing were obtained. Differences in scene-affect as a function of labelled meaning were found. Responses to housing scenes labelled as located in either Memphis, Houston or San Francisco revealed no differences in scene-affect as a function of label meaning. This latter finding was confirmed in a non-repeated measure examination. Differences in the fittingness, potency or relevance of the information provided may account for the pattern of findings. 相似文献
95.
A multivariate statistical method for analyzing spatial patterns of water quality in Georgia and Kansas was tested using data in the US Environmental Protection Agency's STORET data system. Water quality data for Georgia and Kansas were organized by watersheds. We evaluated three questions: (a) can distinctive regional water quality patterns be detected and predicted using only a few water quality variables, (b) are regional water quality patterns correlated with terrestrial biotic regions, and (c) are regional water quality patterns correlated with fish distributions? Using existing data, this method can distinguish regions with water quality very different from the average conditions (as in Georgia), but it does not discriminate well between regions that do not have diverse water quality conditions (as in Kansas). Data that are spatially and temporally adequate for representing large regions and for multivariate statistical analysis are available for only a few common water quality parameters. Regional climate, lithology, and biotic regimes all have the potential to affect water quality, and terrestrial biotic regions and fish distributions do compare with regional water quality patterns, especially in a state like Georgia, where watershed characteristics are diverse. Thus, identifiable relationships between watershed characteristics and water quality should allow the development of an integrated landaquatic classification system that would be a valuable tool for resource management. Because geographical distributions of species may be limited by Zoogeographic and environmental factors, the recognition of patterns in fish distributions that correlate with regional water quality patterns could influence management strategies and aid regional assessments. 相似文献
96.
The historical and regional context to the development of a planning strategy for Barcelona is examined, providing an explanation of the obstacles to development of new towns in the region, and that of Riera de Caldes in particular. The paper analyses the reasons for the failure to develop the new town, and its subsequent reversion to rural uses and a place of pilgrimage for environmentalists. 相似文献
97.
Ulf Wiberg 《Journal of Environmental Planning and Management》1986,29(2):70-74
The computer and telecommunications technology has created new opportunities for developing interaction between offices and enterprises located far away from each other. Even if the market forces favour concentration to R & D centres in the big cities and in university towns, there are expectations that the distance over‐bridging qualities of the new technology can create development opportunities for sparsely populated peripheral areas. In this paper the interplay between the new technology and other important factors in the local and regional environment are discussed with the focus on both opportunities and restrictions. 相似文献
98.
Environmental planning,ecosystem science,and ecosystem approaches for integrating environment and development 总被引:3,自引:0,他引:3
D. Scott Slocombe 《Environmental management》1993,17(3):289-303
Currently popular concepts such as sustainable development and sustainability seek the integration of environment and development
planning. However, there is little evidence that this integration is occurring in either mainstream development planning or
environmental planning. This is a function of the history, philosophies, and evolved roles of both. A brief review of the
experience and results of mainstream planning, environmental planning, and ecosystem science suggests there is much in past
scientific and professional practice that is relevant to the goal of integrated planning for environment and development,
but still such commonly recommended reforms as systems and multidisciplinary approaches, institutional integration, and participatory,
goal-oriented processes are rarely achieved. “Ecosystem approaches,” as developed and applied in ecology, human ecology, environmental
planning, anthropology, psychology, and other disciplines, may provide a more transdisciplinary route to successful integration
of environment and development. Experience with ecosystem approaches is reviewed, their advantages and disadvantages are discussed,
and they are compared to traditional urban and regional planning, environmental planning, and ecosystem science approaches.
Ultimately a synthesis of desirable characteristics for a framework to integrate environment and development planning is presented
as a guide for future work and a criterion for evaluating existing programs. 相似文献
99.
The impact of global warming on winter tourism and skiing: a regionalised model for Austrian snow conditions 总被引:2,自引:1,他引:1
Possible climate change will modify snow-cover depth and change the characteristics of winter tourism and skiing districts.
Our model describes seasonal snow-cover depth related to altitude in six Alpine climate regions as the best fit of all snow
stations. Data cover 30 winter seasons (November to April values) from 1965 to 1995. We modified the data according to a scenario
of temperature and precipitation change (2 °C warming, no precipitation change) and achieve a new simulated snow-cover depth.
The indicators MARP (mean altitude of resident population) and MASPSL (mean altitude of starting point of ski lifts) serve
as references for “critical altitudes” of Austrian districts. A warming implies a reduction of snow in all districts, but
the loss is overproportional in lower altitudes. The direction of economic impacts is clear – income losses and adaptation
costs – but magnitude and time frames remain uncertain.
Received: 24 February 1999 · Accepted: 15 May 1999 相似文献
100.
Rough Set Rule Induction for Suitability Assessment 总被引:4,自引:0,他引:4
Berger PA 《Environmental management》2004,34(4):546-558
The data that characterize an environmental system are a fundamental part of an environmental decision-support system. However, obtaining complete and consistent data sets for regional studies can be difficult. Data sets are often available only for small study areas within the region, whereas the data themselves contain uncertainty because of system complexity, differences in methodology, or data collection errors. This paper presents rough-set rule induction as one way to deal with data uncertainty while creating predictive if–then rules that generalize data values to the entire region. The approach is illustrated by determining the crop suitability of 14 crops for the agricultural soils of the Willamette River Basin, Oregon, USA. To implement this method, environmental and crop yield data were spatially related to individual soil units, forming the examples needed for the rule induction process. Next, four learning algorithms were defined by using different subsets of environmental attributes. ROSETTA, a software system for rough set analysis, was then used to generate rules using each algorithm. Cross-validation analysis showed that all crops had at least one algorithm with an accuracy rate greater than 68%. After selecting a preferred algorithm, the induced classifier was used to predict the crop suitability of each crop for the unclassified soils. The results suggest that rough set rule induction is a useful method for data generalization and suitability analysis. 相似文献