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801.
Fuzzy decision analysis for integrated environmental vulnerability assessment of the mid-Atlantic Region 总被引:20,自引:0,他引:20
Tran LT Knight CG O'Neill RV Smith ER Riitters KH Wickham J 《Environmental management》2002,29(6):845-859
A fuzzy decision analysis method for integrating ecological indicators was developed. This was a combination of a fuzzy ranking
method and the analytic hierarchy process (AHP). The method was capable of ranking ecosystems in terms of environmental conditions
and suggesting cumulative impacts across a large region. Using data on land cover, population, roads, streams, air pollution,
and topography of the Mid-Atlantic region, we were able to point out areas that were in relatively poor condition and/or vulnerable
to future deterioration. The method offered an easy and comprehensive way to combine the strengths of fuzzy set theory and
the AHP for ecological assessment. Furthermore, the suggested method can serve as a building block for the evaluation of environmental
policies. 相似文献
802.
803.
James D. Proctor 《Environmental management》1998,22(3):347-358
/ Public participation in environmental management decisions has frequently led to conflict. This paper examines the role of environmental values in fueling these conflicts, based on a data base and sample content analysis of written public comments solicited in 1994 regarding the highly contentious Clinton Forest Plan (also known as Option 9) proposed for management of federal forests in the US Pacific Northwest. The analysis considered whether those respondents favoring more versus less environmental protection than was offered in Option 9 held entirely different values, identifying which antagonistic values appeared to be most fundamental and where (if at all) values consensus occurred. It also compared values emanating from respondents within and outside the affected region, although few major differences were detected in this regard. Results suggest that strong values differences did exist among those preferring greater versus less environmental protection, in particular as concerned the extent, form, and spatial and temporal scope of justification of their positions, their ideas of forests, and the appropriate role of people in forest management. Disagreement concerned far more than purely environmental values: a major point of difference involved human benefits and harms of the proposed forest plan. Indeed, both sides' positions were overridingly anthropocentric and consequentialist-a values orientation that almost inevitably spells conflict in light of the commonly differentiated social impacts of environmental management decisions. Although public involvement in environmental management thus cannot be expected to lead to a clear and consensual social directive, the Pacific Northwest case suggests that viable environmental management solutions that take this range of values into account can still be crafted.KEY WORDS: Environmental values; Public participation; Clinton Forest Plan; Pacific Northwest 相似文献
804.
Mrs Sue Hare is the education and information services coordinator of the UK Atmospheric Research and Information Centre (ARIC). Professor James Longhurst was recently the director of the ARIC and Joe Buchdahl its global climate change information services coordinator. Professor Longhurst is now head of the Department of Environmental Health and Science, University of the West of England, Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY. Kelvin Williams is a geography consultant and is head of geography at Ysgol y Creuddyn, Penrhyn Bay, Llandudno, Gwynedd LL30 3LB. The pedagogy of atmospheric issues is identified in the context of environmental education in this paper. The UK Atmospheric Research and Information Centre (ARIC) has developed an education programme which has responded to the dynamic issues relating to the atmosphere since the establishment of the ARIC in 1984. The main route for the teaching of atmospheric issues is identified as being through the UK's National Curriculum although public awareness of issues has increased through the media and more recently through government publicity campaigns. 相似文献
805.
Environmental program and audit procedures primarily focus on solving perceived immediate problems and do not provide a context within which to evaluate the work and its importance for the decision maker. Outcome evaluation offers a theory-based model for designing long-term solutions based on stakeholder expectation and, ultimately, ownership of the performance changes. Problem identification as well as the development of actions and their measurement are done with the full participation of those responsible for the implementation of the changes. Ownership of the results is reinforced and, significantly, the decision maker and other interested parties can measure the value or the importance of the work. This article describes how outcome evaluation can be an important tool for federal environmental managers who must respond to the Government Performance and Results Act (1993) and privatesector companies. Used in combination with traditional environmental practices, outcome evaluation can contribute to both the design and the implementation of a successful environmental management program. 相似文献
806.
Design for the Environment (DFE) is a systems-oriented approach for designing more ecologically and economically sustainable product systems. It couples the product development cycle used in business with the physical life-cycle of a product. DFE integrates environmental requirements into the earliest stages of design so total impacts caused by product systems can be reduced. With DFE practices, environmental, performance, cost, cultural, and legal requirements are balanced. Concepts such as concurrent design, total quality management, cross-disciplinary teams, and multiattribute decision making are essential elements of DFE.1 In this article, the authors show how these DFE initiatives can provide the design and product development teams with the training, information, decision support tools, and procedures that ensure improved product development decisions and environmental performance. 相似文献
807.
R. Thomas. James James Martin Tim Wool P F Wang 《Journal of the American Water Resources Association》1997,33(3):661-678
ABSTRACT: The influence of sediment resuspension on the water quality of shallow lakes is well documented. However, a search of the literature reveals no deterministic mass-balance eutrophication models that explicitly include resuspension. We modified the Lake Okeechobee water quality model - which uses the Water Analysis Simulation Package (WASP) to simulate algal dynamics and phosphorus, nitrogen, and oxygen cycles - to include inorganic suspend. ed solids and algorithms that: (1) define changes in depth with changes in volume; (2) compute sediment resuspension based on bottom shear stress; (3) compute partition coefficients for ammonia and ortho-phosphorus to solids; and (4) relate light attenuation to solids concentrations. The model calibration and validation were successful with the exception of dissolved inorganic nitrogen species which did not correspond well to observed data in the validation phase. This could be attributed to an inaccurate formulation of algal nitrogen preference and/or the absence of nitrogen fixation in the model. The model correctly predicted that the lake is light-limited from resuspended solids, and algae are primarily nitrogen limited. The model simulation suggested that biological fluxes greatly exceed external loads of dissolved nutrients; and sediment-water interactions of organic nitrogen and phosphorus far exceed external loads. A sensitivity analysis demonstrated that parameters affecting resuspension, settling, sediment nutrient and solids concentrations, mineralization, algal productivity, and algal stoichiometry are factors requiring further study to improve our understanding of the Lake Okeechobee ecosystem. 相似文献
808.
Arthur L. Fredeen James T. Randerson N. Michele Holbrook Christopher B. Field 《Journal of the American Water Resources Association》1997,33(5):1033-1039
ABSTRACT: Californian annual grassland on sandstone (moderately fertile) and serpentine (very infertile) soils at the Jasper Ridge Biological Preserve, Stanford, California, were exposed to ambient or elevated (ambient + 36 Pa CO2) atmospheric CO2 in open-top chambers since December 1991. We measured ecosystem evapotranspiration with open gas-exchange systems, and soil moisture with time-domain reflectometry (TDR) over 0–15 cm (serpentine) and 0–30 cm (sandstone) depths, at times of peak above ground physiological activity. Evapotranspiration decreased by 12 to 63 percent under elevated CO2 in three consecutive years in the sandstone ecosystem (p = 0.053, p = 0.162, p = 0.082 in 1992, 1993, and 1994, respectively). In correspondence with decreased evapotranspiration, late-season soil moisture reserves in the sandstone were extended temporally by 10 ± 3 days in 1993 and by 28 ± 11 days in 1994. The effect of elevated CO2 on soil moisture was greater in the drier spring of 1994 (419 mm annual rainfall) than in 1993 (905 mm annual rainfall). In the serpentine ecosystem, evapotranspiration and soil moisture reserves were not clearly affected by elevated CO2. Soil water may be conserved in drought-affected ecosystems exposed to elevated CO2, but the amount of conservation appears to depend on the relative importance of transpiration and soil evaporation in controlling water flux. 相似文献
809.
810.