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991.
Ramsey K 《Journal of environmental management》2009,90(6):1972-1980
A tension exists at the heart of efforts to support collaboration with GIS. Many scholars and practitioners seek to support two separate objectives: (1) problem solving and (2) the exploration of diverse problem understandings. GIS applications designed for problem solving often pre-define the problem space by structuring the kind of information that can be considered or the way in which the problem is conceptualized. In doing so, they necessarily privilege particular perspectives and understandings of the problem while marginalizing others. As a result, these initiatives undermine their second objective. This is problematic in the context of contentious environmental decisions which have broad-reaching impacts on people with diverse perspectives and interests. In such contexts, I argue that equitable collaboration is impossible without first emphasizing the exploration of diverse problem understandings. I support this argument theoretically by turning to the literatures on collaborative planning and spatial decision support, and empirically in my analysis of a case study of an effort to construct a GIS for supporting collaborative water resource management in rural Idaho. Reflecting upon the case, I provide a set of recommendations to those seeking to better negotiate the tensions of supporting collaboration with GIS in the context of contentious environmental and natural resource decisions. 相似文献
992.
Lessons for PPGIS from the application of a decision-support tool in the Nova Forest Alliance of Nova Scotia, Canada 总被引:1,自引:0,他引:1
The effectiveness of a decision-support tool created to identify protected-area potential within the Nova Forest Alliance (NFA) of Nova Scotia, Canada is assessed from the perspective of a public participatory geographic information system (PPGIS) approach. The application sought to create an integrated GIS-based decision-support tool for community-focused communication and conservation assessment among NFA partners (including private woodland owners, government agencies, forest companies, and non-government organizations) and potential application within other model forests in Canada. The application illustrated that the GIS-based tool, once set up and populated with the necessary data, was able to generate effective visual alternatives to support decision making within the NFA community and elsewhere. However, from a PPGIS perspective, the application faced challenges that influenced the efficacy of its implementation: (1) limitations arose around data quality, use and sharing policies; (2) although opportunities for participation by the NFA partnership were initiated, these proved insufficient to achieve adequate engagement, buy in and support for the process and outcomes; and (3) the expert-grounded GIS-based tool requires a greater degree of expertise than may currently be present in the community. These challenges limit its ongoing use in the NFA and its potential utility in other model forests. For PPGIS-decision-support applications to be effective in the NFA and elsewhere, it is suggested that the following conditions be met: (1) implementation of geographically based data policies to allow for greater data accessibility, specifically with fewer bureaucratic and private sector barriers; (2) engagement of community partners in the initial project design, goal-setting and subsequent stages, even if this requires extensions to anticipated timelines; and (3) development of effective participatory technical systems that meet the needs of participants without being so complex as to constitute a barrier to their use. 相似文献
993.
The Lyon-Turin High-Speed Rail: The Public Debate and Perception of Environmental Risk in Susa Valley,Italy 总被引:1,自引:1,他引:0
When the construction of the Lyon-Turin segment of the new European high-speed rail network was first publicly announced at
the beginning of the 1990s, it immediately found fierce opposition from the inhabitants of Susa Valley, Italy, one of the
areas to be cut across by such infrastructure. At issue were the project’s potential environmental impact and its consequences
on public health. This study intends to clarify environmental risk perception and public debate between the national government,
local advocacy groups, and the inhabitants of Susa Valley. Two major phases of public reaction were identified: (1) an initial
rebellious period of no real dialog among the project’s major stakeholders (exemplified by the popular “No TAV” [No High Speed
Train] movement), followed by (2) a yielding period of intense multilateral negotiations centered on the activities of the
“Lyon-Turin Environmental Observatory.” The results of a qualitative cross analysis of the residents’ perception of the proposed
high-speed rail revealed that public acceptance of risk in Susa Valley was influenced by the characteristics of hazards perceived
by the residents and by the communicative approach used by the project’s various stakeholders. It also emerged that early
dialog among all the parties involved was critical in forming a personal viewpoint on risk, which, once consolidated, defied
new information and perspectives. Likely, a greater and earlier care taken by the other stakeholders to inform and consult
the local population about the railway would have greatly eased the public debate. 相似文献
994.
Global change affects alpine ecosystems by, among many effects, by altering plant distributions and community composition.
However, forecasting alpine vegetation change is challenged by a scarcity of studies observing change in fixed plots spanning
decadal-time scales. We present in this article a probabilistic modeling approach that forecasts vegetation change on Niwot
Ridge, CO using plant abundance data collected from marked plots established in 1971 and resampled in 1991 and 2001. Assuming
future change can be inferred from past change, we extrapolate change for 100 years from 1971 and correlate trends for each
plant community with time series environmental data (1971–2001). Models predict a decreased extent of Snowbed vegetation and
an increased extent of Shrub Tundra by 2071. Mean annual maximum temperature and nitrogen deposition were the primary a posteriori
correlates of plant community change. This modeling effort is useful for generating hypotheses of future vegetation change
that can be tested with future sampling efforts. 相似文献
995.
It is known that fugitive dust can cause human health and environmental problems, alone or in combination with other air pollutants.
These problems are referred to as ‘external costs’ that have been traditionally ignored. However, there is a growing interest towards quantifying externalities to assist policy
and decision-making. With this in mind, the present study aimed at discussing the environmental regulations that deal with
fugitive dust, the impact of fugitive dust on human health and global climate system, and the available methods for calculating
fugitive dust externalities. The damage cost associated with human health and global environmental problems was predicted
based on the environmental strategy priority model. The damage cost estimated by the model ranged from 40 to 374 EUR/kg of
emitted fugitive dust with a mean value of 120 EUR/kg of emitted fugitive dust. It was also found that PM2.5 and PM10 have contributed to about 60% and 36% of the estimated damage cost, respectively. The remaining 4% was attributed to both
nitrate and sulfate aerosols. 相似文献
996.
Hydro-chemical Survey of Groundwater of Hisar City and Assessment of Defluoridation Methods Used in India 总被引:1,自引:0,他引:1
Ground water quality of Hisar city was assessed for its suitability for drinking purposes. Samples collected from the Bore-wells
(forms a part of municipal water supply) and handpumps (direct consumption) were analyzed for the various physico-chemical
parameters including pH, electrical conductivity, total dissolved salts, total hardness, total alkalinity, sodium, potassium,
calcium, magnesium, carbonate, bicarbonate, chloride and sulfate. The concentrations of magnesium, sodium, potassium, sulfate
and especially of chloride were found moderately higher than the WHO standards for the drinking water. Further a comparison
of fluoride (F−) levels in groundwater of various cities and towns of Haryana state was performed. The relatively higher concentrations of
F− in groundwater of Haryana raise the risk of fluorosis and hence groundwater must be used with proper treatment. Promising
defluoridation methods using locally available materials and technologies are discussed for the prevention and control of
fluorosis. Data were assessed statistically to find the suitable markers of ground water quality as an aid to monitoring groundwater
quality. 相似文献
997.
土壤变暖对土壤微生物活性的影响 总被引:6,自引:0,他引:6
讨论了土壤变暖对土壤微生物活性的影响及其后果。许多研究表明,土壤呼吸与土壤温度呈正相关关系。描述这种关系所用的模式有线性回归分析、Q10关系式、幂关系式、Arrhenius关系式及其它关系式,但这些模式通常都不能准确地估计呼吸率。尽管如此,几乎所有的研究都显示土壤温度强烈地影响土壤微生物活性及呼吸。在一定温度范围内,土壤变暖提高土壤微生物活性及呼吸率。解释这种现象的一种机制是微生物群体组成随温度升高而改变。文章最后指出,为了得出更加明确的结论及更加准确地预测全球变暖对土壤的影响,必须进行更深入地研究。 相似文献
998.
Robert J. Luxmoore William W. Hargrove M. Lynn Tharp Wilfred M. Post Michael W. Berry Karen S. Minser Wendell P. Cropper Jr. Dale W. Johnson Boris Zeide Ralph L. Amateis Harold E. Burkhart V. Clark Baldwin Jr. Kelly D. Peterson 《Environmental Modeling and Assessment》2000,5(2):125-137
Stochastic transfer of information in a hierarchy of simulators is offered as a conceptual approach for assessing forest responses
to changing climate and air quality across 13 southeastern states of the USA. This assessment approach combines geographic
information system and Monte Carlo capabilities with several scales of computer modeling for southern pine species and eastern
deciduous forests. Outputs, such as forest production, evapotranspiration and carbon pools, may be compared statistically
for alternative equilibrium or transient scenarios providing a statistical basis for decision making in regional assessments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
In December 1997, the United Nations Framework Convention on Climate Change (FCCC) adopted the Kyoto Protocol. This paper
describes a framework that models the climatic implications of this international agreement, using Monte Carlo simulations
and the preliminary Intergovernmental Panel on Climate Change emissions scenarios (SRES). Emissions scenarios (including intervention
scenarios), climate sensitivity, and terrestrial carbon sink are the key sampled model parameters. This framework gives prior
probability distributions to these parameters and, using a simple climate model, posterior distributions of global temperature
change are determined for the future.
Our exercise showed that the Kyoto Protocol's effectiveness will be mostly dependent upon which SRES world evolves. In some
worlds the Protocol decreases the warming considerably but in others it is almost irrelevant. We exemplified this approach
with a current FCCC issue, namely “hot air”. This modelling framework provides a probabilistic assessment of climate policies,
which can be useful for decision-makers involved in global climate change management.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
1000.
太湖蓝藻水华预警监测综合系统的构建 总被引:2,自引:2,他引:0
近年来随着浅水型湖泊的富营养化进程不断加快,蓝藻水华暴发现象也频繁出现,采用科学、全面的手段对太湖蓝藻暴发进行预警十分必要。根据太湖蓝藻预警监测中使用的现场巡视、卫星遥感、实验室分析、自动监测等监测技术手段,分别建立各自监测系统,结合各监测系统特点和相互关系,对太湖蓝藻水华预警监测综合系统的构建进行了探讨,以期能够更好地开展太湖蓝藻水华预警监测工作,为确保太湖地区饮用水安全,提高环保部门应对太湖蓝藻水华暴发的能力,为政府决策提供技术支持和保障。 相似文献