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181.
Currently, most tools, guidelines and benchmarks for urban adaptation raise awareness on climate change impacts, assess the city’s vulnerability and/or address the need for adaptation on a policy-level. However, tools that have the ability to implement adaptation solutions in the actual urban planning and design practice seem to be missing. We developed and tested the Adaptation Planning Support Toolbox (APST) to fill this gap. This toolbox supports local policymakers, planners, designers and practitioners in defining the program of demands, in setting adaptation targets, in selecting from more than 60 blue, green and grey adaptation measures and with informed co-creation of conceptual adaptation plans. The APST provides quantitative, evidence-based performance information on (cost)effectiveness of adaptation measures regarding climate resilience and co-benefits. The APST can be used design workshops, to feed dialogues among stakeholders on where and how which ecosystem-based adaptation measures can be applied. Applications of the AST in various settings and context in cities on different continents have illustrated the added value of the toolbox in bringing policy and practice together with help of science. With more and more cities worldwide that will make the step from policymaking to actual adaptation-inclusive urban (re)development practice we foresee a growing demand for such tools.  相似文献   
182.
Researchers have increasingly acknowledged the relative strength of ‘hybrid’ approaches to scenario analysis for exploring the futures of coupled human-nature systems. In this paper, we explain, demonstrate, and provisionally evaluate the usefulness of a simple analytical framework, based on five categories of capital assets, as part of a protocol for overcoming the conversion problem in hybrid scenario analysis. Based on a preliminary application of the framework to a case study in South Africa, we suggest that the five capitals framework has the potential to improve expedience and counter the bias against ‘soft’ drivers in hybrid approaches to scenario analysis. However, in light of the methodological trade-off between rigour and expedience, we suggest that future research needs to compare the available protocols for hybrid scenario analysis by weighing up the relative gain in scenario quality versus the relative cost of scenario construction.  相似文献   
183.
The sustainable management of coastal natural resources inevitably involves identifying stakeholder conflicts and developing planning processes that prevent these conflicts from becoming intractable disputes. This study links environmental conflict to specific areas within a large ecological system. Specifically, we use Geographic Information Systems (GIS) to map potentially competing stakeholder values associated with establishing protected areas in Matagorda Bay, Texas. By overlaying multiple values associated with a range of stakeholders across space, we are able to identify hotspots of potential conflict as well as areas of opportunity for maximizing joint gains. Mapping stakeholder conflict is an approach to proactively locate potential controversy in response to a specific environmental management proposal and guide decision makers in crafting planning processes that mitigate the possibility of intractable disputes and facilitate the implementation of sustainable coastal policies. Results indicate that under different management scenarios, protected area proposals will generate more conflict in specific areas. Most notably, regulated uses would produce the greatest degree of conflict on or near shore, particularly at the mouth of the Colorado River. Additionally, of all the management scenarios evaluated, the prohibition of coastal structural development would generate the overall highest level of conflict within the Bay. Based on the results, we discuss the policy implications for environmental managers and provide guidance for future research on location-based conflict management within the coastal margin.  相似文献   
184.
Water and land resources in Thailand are increasingly under pressure from development. In particular, there are many resource conflicts associated with agricultural production in northern Thailand. Communities in these areas are significantly constrained in the land and water management decisions they are able to make. This paper describes the application of a data mining approach to describing and simulating farmers' decision rules in a catchment in northern Thailand. This approach is being applied to simulate social, economic and biophysical constraints on farmers' decisions in these areas as part of an integrated water management model.  相似文献   
185.
ABSTRACT: Ground water is a vital water resource in the Choushui River alluvial fan in Taiwan. A significantly increased demand for water, resulting from rapid economic development, has led to large scale ground water extraction. Overdraft of ground water has considerably lowered the ground water level, and caused seawater intrusion, land subsidence, and other environmental damage. Sound ground water management thus is essential. This study presents a decision support system (DSS) for managing ground water resources in the Choushui River alluvial fan. This DSS integrates geographic information, ground water simulation, and expert systems. The geographic information system effectively analyzes and displays the spatially varied data and interfaces with the ground water simulation system to compute the dynamic behavior of ground water flow and solute transport in the aquifer. Meanwhile, a ground water model, MODFLOW‐96, is used to determine the permissible yield in the Choushui River alluvial fan. Additionally, an expert system of DSS employs the determined aquifer permissible yield to assist local government agencies in issuing water rights permits and managing ground water resources in the Choushui River alluvial fan.  相似文献   
186.
沿空窄煤柱锚网带支护的巷道稳定性研究   总被引:1,自引:1,他引:0  
锚杆支护是煤矿采准巷道的重要支护方式 ,沿空留巷技术是回采巷道支护技术改革的主要方面。笔者将两种技术相结合 ,用于保证回采巷道的稳定。在现场矿压观测的基础上 ,讨论了支承压力分布规律和窄煤柱护巷机理 ,运用极限平衡理论计算出护巷煤柱宽度 ,同时结合数值分析和现场巷道变形以观测结果 ,实践证明 ,只要设计参数合理 ,施工质量满足要求 ,沿空窄煤柱锚网带支护技术就可以保证回采巷道的稳定  相似文献   
187.
This article focuses on agricultural production in lift irrigation schemes along the White Nile in the Sudan. A comparison is drawn between the theoretical forecast and actual practical experience regarding the feasibility of transferring management from government-run parastatal organizations to private farmer organizations. Although the theoretical model indicates that farmers should be able to cover the cost of managing the river lift irrigation systems, field data show, however, that farmers growing wheat are barely able to break even. Even assuming a doubling of the present wheat yields, the cash surplus earned would only suffice for fuel to operate the pumps. Under these circumstances, it is not surprising that, contrary to government expectations, the private sector has been unenthusiastic about taking over management of White Nile river lift schemes. The lessons that emerge from this study indicate that unplanned and rapid withdrawal of state management can lead to negative results. The transfer of management responsibility for the river pumps does not appear to influence economic performance considerably, which depends on the wider context of the country's economic, political and institutional environment, within which the agricultural sector functions.  相似文献   
188.
ABSTRACT: A significant portion of all pollutants entering surface waters (streams, lakes, estuaries, and wetlands) derives from non-point source (NPS) pollution and, in particular, agricultural activities. The first step in restoring a water resource is to focus on the primary water quality problem in the watershed. The most appropriate NPS control measures, which include best management practices (BMPs) and landscape features, such as wetlands and riparian areas, can then be selected and positioned to minimize or mitigate the identified pollutant(s). A computer-based decision sup. port and educational software system, WATERSHEDSS (WATER, Soil, and Hydro-Environmental Decision Support System), has been developed to aid managers in defining their water quality problems and selecting appropriate NPS control measures. The three primary objectives of WATERSHEDSS are (1) to transfer water quality and land treatment information to watershed managers in order to assist them with appropriate land management/land treatment decisions; (2) to assess NPS pollution in a watershed based on user-supplied information and decisions; and (3) to evaluate, through geographical information systems-assisted modeling, the water quality effects of alternative land treatment scenarios. WATERSHEDSS is available on the World Wide Web (Web) at http://h2osparc.wq.ncsu.edu .  相似文献   
189.
从溧  王媛 《四川环境》1994,13(1):26-29
本文介绍了在环境监测中,经试验研究,确定的用阳极溶出伏安法,连续分析环境样品中重金属Cu,Pb,Cd的最佳条件,即用悬汞电极做工作电极,用0.1M离氯酸做支持电解质,纯氮除氧。当PH值取2-7,富集电位数-1.1~-1.2V时,不但可连续测定一定浓度范围的重金属Cd,Pb,CU;而且方法灵敏度高,精密良好,线性相关关系可达0.9990,回收率达85-115%,获得了良好的分析效果。  相似文献   
190.
Residential lakeshore development is causing increasing pressure on the lacustrine environment. Traditional landscaping patterns produce lakes ringed with lawns at the expense of the naturally occurring shoreline habitat. In this work, we present a mathematical model to select path locations to minimize impacts on the lakeshore environment, while providing convenient access to the landowners.  相似文献   
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