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931.
ABSTRACT: This paper pursues more specifically the recommendations of a recent National Research Council report recommending greater attention to research on institutions in the field of water resource management. The important challenge for the future in institutional research lies in going beyond the observation that institutions are important and in explaining instead how institutions actually affect management options and outcomes. It is possible to illuminate the relationships between institutional features and water management through comparative institutional research. This paper offers recommendations for studying water institutions in a comparative context, including methodological recommendations concerning approaches to comparative institutional research, and topics for comparative institutional research that appear especially fruitful at this time. The example of conjunctive management is used to illustrate the importance of institutional factors in water management, drawing to some extent on the authors’ recent experience with a comparative study of conjunctive management institutions.  相似文献   
932.
ABSTRACT: Earthen waste storage structures (EWSS) associated with large confined (concentrated) animal feeding operations (CAFOs) were evaluated for their potential to impact water resources in Iowa. A representative sample of 34 EWSS from a digital database of 439 lagoons and basins permitted between 1987 and 1994 was analyzed. Eighteen percent (6 of 34) directly overlie alluvial aquifers that are used widely for potable water supply. Ninety‐four percent (29 of 31) were constructed below the water table based on EWSS depth data. At 65 percent of EWSS (22 of 34), 50 percent or more of the manure‐spreading area (MSA) has a water‐table depth less than 1.6 m. At 74 percent of EWSS (25 of 34), 90 percent or more of the MSA contains soil with vertical K exceeding 25.4 mm/hr. Seventy‐one percent (24 of 34) occur where 10 percent or less of the MSA is frequently flooded. No significant differences were found among leakage rates due to aquifer vulnerability class or surficial material. However, at least 50 percent of EWSS (14 of 28) leaked at rates significantly greater than 1.6 mm/d under the new construction standard. The estimated 5,000 unregulated CAFOs may have a greater potential to impact water resources in Iowa.  相似文献   
933.
ABSTRACT: Making decisions for environmental management is a complex task due to the multiplicity and diversity of technological choices. Furthermore, the exploitation of natural resources and the preservation of the natural environment imply objectives that are often in conflict within a sustainable development paradigm. Managers and other decision makers require techniques to assist them in understanding strategic decision making. This paper illustrates the use of a multiple‐objective decision‐making methodology and an integrative geographical information system‐based decision‐making tool developed to help watershed councils prioritize and evaluate restoration activities at the watershed level. Both were developed through a multidisciplinary approach. The decision‐making tool is being applied in two watersheds of Oregon's Willamette River Basin. The results suggest that multiple‐objective methods can provide a valuable tool in analyzing complex watershed management issues.  相似文献   
934.
ABSTRACT: Changes in watershed management and policy in Hawaii are an instructive case study on the evolution of resource management from a traditional vertically integrated system, to a segmented central government‐based system, and now towards a community and watershed focus. The rise of European social and economic influences coupled with the precipitous decline in the Hawaiian population in the years following European contact led to the destruction of traditional management structures. Subsequently, the dominance of outside interests in Hawaii society and politics, culminating with the sugar industry, facilitated the unrestricted use and privatization of land and water resources. The post‐World War II era ushered in fundamental changes in Hawaii society and politics including renewed appreciation of traditional management practices. Government policies, increased community interest in resource management, and a renaissance in Hawaiian culture have converged in recent years to facilitate the development of new management structures that draw on both traditional and contemporary management. These structures hold great promise for improving Hawaiian watershed management. Our observations suggest that other jurisdictions may find it productive to examine traditional management and policy structures and try to relate them to contemporary community‐based resource management policies and activities.  相似文献   
935.
ABSTRACT: In the environmental and agricultural conservation planning process, more efficient and effective tools are needed for planners to assist private landowners with making wiser land use decisions. Current methods are slow, inefficient, and costly. Scientific techniques have not been fully implemented within the planning process, yet such plans are increasingly needed to meet water quality and Total Maximum Daily Load (TMDL) requirements. The objectives of this study are to (a) utilize the web for accessing an integrated science‐based land use decision support system; (b) link decision tools, models, and databases to the user via the web; (c) link distributed models and databases for enhanced planning efficiency; and (d) integrate the above into an easily usable and readily accessible system. The procedures resulting in the initial design involved planning expertise and focus groups' input. The system was developed in partnership with the Natural Resources Conservation Service of the U.S. Department of Agriculture and several state agencies. A survey of 150 certified conservation planners, the end users, was conducted to identify the data sets and planning tools needed. Data, tools, and models then were selected and integrated into a web accessible system. Specifically, the first generation used a web interactive Geographic Information System (GIS) that overlaid onto digital orthoquads and/or soils polygons field boundaries, transportation, hydrologic features (such as drains, rivers, lakes, etc.), and high pesticide risk runoff or infiltration areas. Conservation planners found they could save time with the system. Clients could access the system quickly to help them prepare for meeting with their planner. Previously acquiring GIS maps in some cases had been a lengthy process that limited use of the information in land use decisions.  相似文献   
936.
Decision Support System for Managing Oil Spill Events   总被引:3,自引:0,他引:3  
The Mediterranean environment is exposed to various hazards, including oil spills, forest fires, and floods, making the development of a decision support system (DSS) for emergency management an objective of utmost importance. The present work presents a complete DSS for managing marine pollution events caused by oil spills. The system provides all the necessary tools for early detection of oil-spills from satellite images, monitoring of their evolution, estimation of the accident consequences and provision of support to responsible Public Authorities during clean-up operations. The heart of the system is an image processing–geographic information system and other assistant individual software tools that perform oil spill evolution simulation and all other necessary numerical calculations as well as cartographic and reporting tasks related to a specific management of the oil spill event. The cartographic information is derived from the extant general maps representing detailed information concerning several regional environmental and land-cover characteristics as well as financial activities of the application area. Early notification of the authorities with up-to-date accurate information on the position and evolution of the oil spill, combined with the detailed coastal maps, is of paramount importance for emergency assessment and effective clean-up operations that would prevent environmental hazard. An application was developed for the Region of Crete, an area particularly vulnerable to oil spills due to its location, ecological characteristics, and local economic activities.  相似文献   
937.
The United States Forest Service is required to analyze road systems on each of the national forests for potential environmental impacts. We have developed a novel and inexpensive way to do this using the Ecosystem Management Decision Support program (EMDS). We used EMDS to integrate a user-developed fuzzy logic knowledge base with a grid-based geographic information system to evaluate the degree of truth for assertions about a roads environmental impact. Using spatial data for natural and human processes in the Tahoc National Forest (TNF, California, USA), we evaluated the assertion the road has a high potential for impacting the environment. We found a high level of agreement between the products of this evaluation and ground observations of a TNF transportation engineer, as well as occurrences of road failures. We used the modeled potential environmental impact to negatively weight roads for a least-cost path network analysis to 1573 points of interest in the forest. The network analysis showed that out of 8233 km of road analyzed in the forest, 3483 km (42%) must be kept in a modified road network to ensure access to these points. We found that the modified network had improved patch characteristics, such as significantly fewer cherry stem roads intruding into patches, an improved area-weighted mean shape index, and larger mean patch sizes, as compared to the original network. This analysis system could be used by any public agency to analyze infrastructure for environmental or other risk and included in other mandated analyses such as risks to watersheds.  相似文献   
938.
层次分析模糊群体决策法评价大气环境质量   总被引:2,自引:0,他引:2  
李德豪  陈建军 《化工环保》1998,18(4):237-241
提出了层次分析模糊群体决策评价方法以层次分析法作定权方法,采用模糊群体决策法中的Borda法为评价方法,对大气环境质量进行评价,并将评价结果与灰色聚类法,模糊综合评判法所得评价结果进行对比,结果令人满意。  相似文献   
939.
ABSTRACT: Ground water is a vital resource in the Yun-Lin area of Taiwan. A substantial amount is continuously extracted, creating adverse effects such as land subsidence and seawater intrusion. Minimizing these negative impacts depends on regulating the rate of groundwater withdrawal. An optimal yield must be determined to establish a sound water management policy. A wide range of safe yields for Yun-Lin have already been proposed based on constant hydrological and hydrogeological parameters. By extending the results of those investigations, this study presents a decision analysis model. The optimal yield concept is introduced as well. The proposed model incorporates a probability density function for rainfall recharge and a loss function, derived from fluctuations in the ground water table. Through decision analysis, the optimum yield is obtained by minimizing the expected value of the loss function. The optimal yield varies monthly because the probability density function is time dependent. Analysis results suggest that the cumulative optimum yield of ground water in the area is 1.26 × 108 m3/year. If the probability distribution function for rainfall recharge is modified as new precipitation data become available, the above suggested yield may require revision in the future.  相似文献   
940.
Sustainable development and the definition of indicators to assess progress towards sustainability have become a high priority in scientific research and on policy agendas. In this paper, we propose a consistent and comprehensive framework of principles, criteria and indicators (PC&I) for sustainability assessment of agricultural systems, referred to as the Sustainability Assessment of Farming and the Environment (SAFE) framework. In addition we formulate consistent and objective approaches for indicator identification and selection. The framework is designed for three spatial levels: the parcel level, the farm level and a higher spatial level that can be the landscape, the region or the state. The SAFE framework is hierarchical as it is composed of principles, criteria, indicators and reference values in a structured way. Principles are related to the multiple functions of the agro-ecosystem, which go clearly beyond the production function alone. The multifunctional character of the agro-ecosystem encompasses the three pillars of sustainability: the environmental, economic and social pillars. Indicators and reference values are the end-products of the framework. They are the operational tools that are used for evaluating the sustainability of the agro-ecosystems. The proposed analytical framework is not intended to find a common solution for sustainability in agriculture as a whole, but to serve as an assessment tool for the identification, the development and the evaluation of agricultural production systems, techniques and policies.  相似文献   
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