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131.
Multiple criteria evaluation (MCE) is often used with GIS to identify suitable sites for multi-purpose development such as ecotourism. Typically, expert or stakeholder consultation is used to identify weights reflecting the relative importance of map layers representing different criteria. The objective of this study was to evaluate a new consultative approach to GIS-based MCE, using ecotourism development in Kurdistan, Iraq, as a case study. In an initial and follow-up consultation, stakeholders were asked not only to assess the relative importance of different map layers for ecotourism development, but also to identify specific sites suitable for ecotourism. Seventy-eight ecotourism destinations nominated by participants had significantly higher MCE scores than a set of 58 locations chosen without reference to stakeholders (t-test = 21.16; p < 0.001). The approach thus provides a straightforward means of assessing the consistency of stakeholder input into MCE and could be adapted for use in other site suitability assessments.  相似文献   
132.
Planning researchers traditionally conceptualize learning as cognitive changes in individuals. In this tradition, scholars assess learning with pre- and post-measures of understandings or beliefs. While valuable for documenting individual change, such methods leave unexamined the social processes in which planners think, act, and learn in groups, which often involve the use of technical tools. The present interdisciplinary research program used Learning Sciences research methods, including conversation analysis, interaction analysis, and visualization of discourse codes, to understand how tools like agent-based models and geographic information systems mediate learning in planning groups. The objective was to understand how the use of these tools in participatory planning can help stakeholders learn about complex environmental problems, to make more informed judgments about the future. The paper provides three cases that illustrate the capacity of such research methods to provide insights into planning groups’ learning processes, and the mediating roles of planning tools.  相似文献   
133.
酸化模型及其在确定酸沉降临界负荷中的应用   总被引:18,自引:4,他引:14  
简述了国外近10年来在酸沉降影响研究中,为预测酸沉降对土壤、地表水、地下水和湖泊的长期影响而开发的各种酸化模型,经比较分析,归纳出建立这此匠基本方法及应用于确定酸沉降临界负葆的基本原理。  相似文献   
134.
In order to resolve the spatial component of the design of a water quality monitoring network, a methodology has been developed to identify the critical sampling locations within a watershed. This methodology, called Critical Sampling Points (CSP), focuses on the contaminant total phosphorus (TP), and is applicable to small, predominantly agricultural-forested watersheds. The CSP methodology was translated into a model, called Water Quality Monitoring Station Analysis (WQMSA). It incorporates a geographic information system (GIS) for spatial analysis and data manipulation purposes, a hydrologic/water quality simulation model for estimating TP loads, and an artificial intelligence technology for improved input data representation. The model input data include a number of hydrologic, topographic, soils, vegetative, and land use factors. The model also includes an economic and logistics component. The validity of the CSP methodology was tested on a small experimental Pennsylvanian watershed, for which TP data from a number of single storm events were available for various sampling points within the watershed. A comparison of the ratios of observed to predicted TP loads between sampling points revealed that the model's results were promising.  相似文献   
135.
以马尾松为指示植物,对韶关的土壤进行了长期淋溶模拟并记录其化学状态。结果发现,土壤溶液的pH值下降到4.0,Bs值下降到几乎为零,有较大量的A1离子溶出。最后选取土壤溶液pn〉4.0、KS〉10%和[Al^3+]〈0.1mmol/L为临界化学指标,参考国内外应用广泛的MAGIC模型和SMART模型,确定韶关酸沉降临界负荷(S的临界负荷)为14.1keq/hm^2.a。  相似文献   
136.
This article presents a case study of Toxics Release Inventory (TRI) air pollution exposure risks across metropolitan St. Louis. The first section critically reviews environmental justice research and related barriers to environmental risk management. Second, the paper offers a conventional analysis of the spatial patterns of TRI facilities and their surrounding census block group demographics for metropolitan St. Louis. Third, the article describes the use of an exposure risk characterization for 319 manufacturers and their air releases of more than 126 toxic pollutants. This information could lead to more practical resolutions of urban environmental injustices. The analysis of TRIs across metropolitan St. Louis shows that minority and low-income residents were disproportionately closer to industrial pollution sources at nonrandom significance levels. Spatial concentrations of minority residents averaged nearly 40% within one kilometer of St. Louis TRI sites compared to 25% elsewhere. However, one-fifth of the region's air pollution exposure risk over a decade was spatially concentrated among only six facilities on the southwestern border of East St. Louis. This disproportionate concentration of some of the greatest pollution risk would never be considered in most conventional environmental justice analyses. Not all pollution exposure risk is average, and the worst risks deserve more attention from environmental managers assessing and mitigating environmental injustices.  相似文献   
137.
Pelling M 《Disasters》2007,31(4):373-385
This paper develops a framework based on procedural, methodological and ideological elements of participatory vulnerability and risk assessment tools for placing individual approaches within the wide range of work that claims a participatory, local or community orientation. In so doing it draws on relevant experience from other areas of development practice from which the disasters field can learn. Participatory disaster risk assessments are examined for their potential to be empowering, to generate knowledge, to be scaled up, to be a vehicle for negotiating local change and as part of multiple-methods approaches to disaster risk identification and reduction. The paper is a response to an international workshop on Community Risk Assessment organised by ProVention Consortium and the Disaster Mitigation for Sustainable Livelihoods Programme, University of Cape Town. The workshop brought together practitioners and academics to review the challenges and opportunities for participatory methodologies in the field of disaster risk reduction. In conclusion the contribution made by participatory methodologies to global disaster risk reduction assessment and policy is discussed.  相似文献   
138.
The ranking of air quality control measures according to a number of evaluation criteria and with the participation of a large number of interested publics is demonstrated. A pilot study for the South Coast Air Quality Management District of California serves as the reference point. Several methodological considerations are addressed, such as: (a) the enhancement of criterion priorities to account for the variability among the performance of the control measures when incommensurable impact levels are applied: (b) the derivation of alternative rankings according to the priorities of potential coalitions; (c) the assessment of the potential acceptability of a collective ranking given the degree of solidarity among participants with similar interest affiliations; and (b) the assessment of the extent to which the performance of specific control measures may override priority differences and lead to insignificant ranking differences.  相似文献   
139.
European critical loads and novel dynamic modelling data have been compiled under the LRTAP Convention by the Coordination Centre for Effects. In 2000 9.8% of the pan-European and 20.8% of the EU25 ecosystem area were at risk of acidification. For eutrophication (nutrient N) the areas at risk were 30.1 and 71.2%, respectively. Dynamic modelling results reveal that 95% of the area at risk of acidification could recover by 2030 provided acid deposition is reduced according to present legislation. Insight into the timing of effects of exceedances of critical loads for nutrient N necessitates the further development of dynamic models.  相似文献   
140.
In this study critical load functions and target load functions of nitrogen and sulphur deposition with respect to acidity and minimum base cation to aluminium ratio were calculated with the SAFE model using three different averaging strategies: (1) averaging based on current forest generation, (2) averaging based on next generation and (3) averaging based on the entire simulation period. From the results it is evident that although target load calculation and indeed critical load calculation is straight forward, there is a problem in translating a predicted recovery according to the target load calculation back to a site-specific condition. We conclude that a policy strategy for emission reductions that ensures recovery, according to calculated target load functions, is likely to be beneficial from an ecosystem point of view. However, such a strategy may not be sufficient to achieve actual non-violation of the chemical criteria throughout the seasonal or rotational variations. To address this issue we propose a method for calculating dynamic critical loads which ensures that the chosen criteria is not violated.  相似文献   
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