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791.
中国1997-2006年可持续发展动态测度分析 总被引:2,自引:1,他引:1
利用生态足迹分析法对中国1997-2006年的生态足迹与生态承载力进行核算,从而定量测度近10年来中国的可持续发展状况,根据结果对生态足迹的供给和需求进行分析并提出相应的建议和对策.结果表明:10年来,中国的生态足迹快速增长,由1997年的1.287 hm2增长到2006年的1.941 hm2,人均生态赤字从1997年的0.596 9hm2增长到2006年的1.267 0 hm2,自然生态系统处于不可持续的发展状态; 在生态足迹的构成中,能源和水域的生态赤字最为严重,远未满足供需平衡;此外,万元GDP占用生态足迹从1997年的2.014 8 hm2降低到2006年的1.209 8hm2,说明中国资源利用效率提高较快,经济增长方式在向良性发展. 相似文献
792.
突发事件应对的物资保障分析 总被引:2,自引:1,他引:1
周定平 《中国安全科学学报》2008,18(3):5-9
从突发事件应对物资保障的特征与价值入手,提出突发事件应对物资保障的基本要求;根据当前我国突发事件应对的物资保障中暴露出来的问题,揭示引发当前突发事件应对物资保障不足的深层次原因;从应对物资的需求、筹集、配置、调度等方面分析,提出我国突发事件应对的物资保障体系的架构设想。有关研究成果将对我国突发事件应对物资保障具有一定的启发和参考意义。 相似文献
793.
绿色供应链管理:企业经营管理的趋势 总被引:36,自引:0,他引:36
在供应链的各个阶段中从原材料获取到产品的制造、运输、使用过程都会产生废弃物,对环境造成严重的污染,威胁人类的健康和生态系统系统。为此,本文提出了以供应链管理的概念,并讨论了它的主要内容以及实施绿色供应链管理的应用前景。 相似文献
794.
高剑平 《中国环境管理干部学院学报》2010,20(6):53-55,58
随着近年来两岸关系的缓和,金门县政府将金门未来定位于"国际观光休闲岛屿",重点发展旅游和教育两大产业。然而,淡水资源的缺乏成为了实现这一目标的现实瓶颈。从气候、地形、经济等方面分析金门地区淡水资源的来源及淡水供应现状,并从开源和节流两方面提出金门地区淡水供应问题的解决途径。 相似文献
795.
Brian J. Harshburger Karen S. Humes Von P. Walden Brandon C. Moore Troy R. Blandford Albert Rango 《Journal of the American Water Resources Association》2010,46(3):603-617
Harshburger, Brian J., Karen S. Humes, Von P. Walden, Brandon C. Moore, Troy R. Blandford, and Albert Rango, 2010. Evaluation of Short-to-Medium Range Streamflow Forecasts Obtained Using an Enhanced Version of SRM. Journal of the American Water Resources Association (JAWRA) 46(3):603-617. DOI: 10.1111/j.1752-1688.2010.00437.x Abstract: As demand for water continues to escalate in the western United States, so does the need for accurate streamflow forecasts. Here, we describe a methodology for generating short-to-medium range (1 to 15 days) streamflow forecasts using an enhanced version of the Snowmelt Runoff Model (SRM), snow-covered area data derived from MODIS products, data from Snow Telemetry stations, and meteorological forecasts. The methodology was tested on three mid-elevation, snowmelt-dominated basins ranging in size from 1,600 to 3,500 km2. To optimize the model performance and aid in its operational implementation, two enhancements have been made to SRM: (1) the use of an antecedent temperature index method to track snowpack cold content, and (2) the use of both maximum and minimum critical temperatures to partition precipitation into rain, snow, or a mixture of rain and snow. The comparison of retrospective model simulations with observed streamflow shows that the enhancements significantly improve the model performance. Streamflow forecasts generated using the enhanced version of the model compare well with the observed streamflow for the earlier leadtimes; forecast performance diminishes with leadtime due to errors in the meteorological forecasts. The three basins modeled in this research are typical of many mid-elevation basins throughout the American West, thus there is potential for this methodology to be applied successfully to other mountainous basins. 相似文献
796.
Sustainability of rural water supply programs in developing countries is still an elusive goal. It is widely accepted that, as a rule, they have failed to deliver benefits to society in the long run. Emphasis has frequently been placed on the short‐term activities. Fast production of new schemes is thus a common strategy, prioritizing the engineering component, while sidestepping social and participatory issues and community empowerment. In 2006, the Government of Tanzania launched a national program to meet water sector targets set out in the Millennium Development Goals by the year 2015. In this study we evaluate key features of the program on a sustained basis. There is evidence that the Government is promoting more sustained facilities, focusing on cost recovery and on ‘decentralization by devolution’. Nevertheless, there are several shortcomings which threaten the long‐term functionality of the infrastructure that has to be built. In light of the implementation of the program, and based on the outputs of its pilot phase, we review the factors that can determine its sustainability. 相似文献
797.
G. Hugh Sidaway 《The Environmentalist》2008,28(3):327-330
The 11th report of COMARE (Committee on Medical Aspects of Radiation in the Environment) established that the incidence of
some childhood cancers, including leukaemia, is inversely related to population density in England, Wales and Scotland, and
is particularly high in Buckinghamshire. Using a photographic archive survey, the present paper notes that population density
is also inversely related to overhead wire domestic electricity supply in Buckinghamshire. Factors associated with domestic
electricity supply may be relevant to the geographical distribution of some childhood cancers. 相似文献
798.
Ensemble of corrosion indices was combined to study the corrosion tendency of the drinking water supply at the University
of Benin, Nigeria. The experimental results were analysed in terms of three corrosion indices-Langelier Index, Ryznar Index
and Larson–Skold Index. According to the evaluation, the Langelier Index ranged from −5.569 to −3.684, Ryznar Index was between
13.340 and 16.418 while the Larson–Skold Index was between 1.191 and 31.750. Results indicated that the water may be corrosive.
A regression of these indices on iron concentration (ppm) showed that Langelier Index, Ryznar Index and Larson–Skold Index
have R
2 of 0.5868, 0.6577 and 0.7063, respectively. The positive correlation between iron levels and the corrosion indices suggested
that iron levels were directly related to increase in corrosion tendency. 相似文献
799.
Dustin Garrick Katharine Jacobs Gregg Garfin 《Journal of the American Water Resources Association》2008,44(2):381-398
Abstract: Declining reservoir storage has raised the specter of the first water shortage on the Lower Colorado River since the completion of Glen Canyon and Hoover Dams. This focusing event spurred modeling efforts to frame alternatives for managing the reservoir system during prolonged droughts. This paper addresses the management challenges that arise when using modeling tools to manage water scarcity under variable hydroclimatology, shifting use patterns, and institutional complexity. Assumptions specified in modeling simulations are an integral feature of public processes. The policymaking and management implications of assumptions are examined by analyzing four interacting sources of physical and institutional uncertainty: inflow (runoff), depletion (water use), operating rules, and initial reservoir conditions. A review of planning documents and model reports generated during two recent processes to plan for surplus and shortage in the Colorado River demonstrates that modeling tools become useful to stakeholders by clarifying the impacts of modeling assumptions at several temporal and spatial scales. A high reservoir storage‐to‐runoff ratio elevates the importance of assumptions regarding initial reservoir conditions over the three‐year outlook used to assess the likelihood of reaching surplus and shortage triggers. An ensemble of initial condition predictions can provide more robust initial conditions estimates. This paper concludes that water managers require model outputs that encompass a full range of future potential outcomes, including best and worst cases. Further research into methods of representing and communicating about hydrologic and institutional uncertainty in model outputs will help water managers and other stakeholders to assess tradeoffs when planning for water supply variability. 相似文献
800.
D.M. White H.M. Clilverd A.C. Tidwell L. Little M.R. Lilly Molly Chambers D. Reichardt 《Journal of the American Water Resources Association》2008,44(2):293-304
Abstract: Many arctic lakes freeze completely in winter. The few that retain unfrozen water for the entire winter period serve as overwintering fish habitat. In addition to serving as fish habitat, water in arctic lakes is needed for industrial and domestic use. Permits for water extraction seek to maximize water use without impacting dissolved oxygen (DO) levels and endangering fish habitat. The relationship between lake volume, winter DO budget, and extraction of water through pumping has historically not been well understood. A management model that could estimate end‐of‐winter DO would improve our understanding of the potential impacts of different management strategies. Using under‐ice DO measurements (November to April) taken from two natural lakes and one flooded gravel mine on the North Slope of Alaska, a physically based model was developed to predict end‐of‐winter DO concentration, water‐column DO profiles, and winter oxygen depletion rate in arctic lakes during periods of ice cover. Comparisons between the measured and model‐predicted oxygen profiles in the three study lakes suggest that the depth‐based DO modeling tool presented herein can be used to adequately predict the amount of DO available in arctic lakes throughout winter. 相似文献