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51.
ABSTRACT: The growing demands by the public for a more active role in planning have recently generated considerable interest among researchers and planners in the subject of public involvement techniques. Numerous surveys have found that standard public participation techniques (e.g., public hearings) by themselves are considered inadequate. Several techniques that have potential for overcoming some of the limitations of standard public involvement techniques have recently been developed. This paper describes several of these new techniques and analyzes each of them in terms of their potential utility in water resources planning.  相似文献   
52.
ABSTRACT: Procedures are presented for comparing and evaluating alternative engineering designs for a particular water resources project. By using certain aspects of fuzzy set theory, it is possible to introduce both quantitative and qualitative considerations into the decisionmaking process. In addition, the viewpoints of the various interest groups involved with the water resources development can be realistically incorporated by the evaluation techniques for the alternative designs. Methods are given for eliminating undesirable alternatives and thereby obtaining a reduced set of possible feasible solutions to the problem. Because of the flexibility of the evaluation methods, the viable alternatives should not only satisfy economical, technical. environmental and other types of constraints, but these possible solutions should be politically feasible as well. A method is formulated for checking the sensitivity of the feasible results with respect to the factors that are considered in the analysis.  相似文献   
53.
ABSTRACT: An extensive research program in hydrometeorology was recently initiated in the Chicago region. Major objectives are to 1) develop a real-time, prediction-monitoring system for storm rainfall using a combination of weather radar and telemetered raingage data, 2) determine precipitation measurement requirements for hydrologic design, operation, and modeling purposes, 3) define the time-space characteristics of heavy rainstorms in the Chicago urban area, and 4) establish methods for applying the Chicago findings in other cities. Basic components of the field measurement program are a network of over 300 recording raingages in 4000 mi2 in and around Chicago, plus two sophisticated weather radar systems for obtaining real-time information on storm parameters pertinent to optimizing operation of urban water resources systems. The raingage networks are to be used to compile information relevant to both design and operational aspects of urban hydrology. Radars are to be used primarily in developing the real-time operational techniques. Testing and evaluation of the real-time operational system will be done in cooperation with the Metropolitan Sanitary District of Chicago, operator of one of the most complex urban water control systems among major metropolitan areas.  相似文献   
54.
ABSTRACT: The detection of change in a hydrologic varaible, particularly water quality, is a current problem. A method is presented for testing whether there has been a shift in the mean of a hydrologic variable based on the well established bivariate normal distribution theory. In this technique, the dependent, or target, and the independent, or control, variables are formed as weighted linear combinations of the mean values at a number of locations in a selected target and control area. The weighting factors are determined based on a mathematical programming technique which minimizes the conditional coefficient of variation thereby minimizing the number of observations required to detect a change of a preselected magnitude in the mean of the target area. The result is a situation where a savings in the number of observations required to detect a change is a consequence of adding more stations: the space-time tradeoff. Two applications of the technique are presented, the first using electrical conductivity (EC) data from two sets of river basins and the second using EC data from a set of basins as the target variable and annual discharge as the control. The results indicate that a significant savings in time can be achieved by using this method.  相似文献   
55.
Recent and rapid landscape changes have occurred over large areas in Mediterranean Basin. Wildfires and human activities are the most important disturbances at landscape-level due to their ecological and socio-economic impacts. The increasing demand which society places on the forest landscapes has led us to develop a tool to identify the economic landscape value around natural protected areas. Our research focused on the integration of social, ecological and economic components of landscape management based on stated social preferences and contingent valuation method (CVM). Landscape value research has been motivated by the need to assist land use planning and environmental management.Geographic Information Systems (GIS) have provided new opportunities to spatially distributed modeling of landscape quality. Correlations were found between the representativeness of the landscape and its sense of belonging, and the contingent rating. Landscape with intensive agricultural practices and mining areas were the least preferred landscapes. There was a notable variation in the economic landscape value attributed to the study area based on the considered CVM scenario, ranging from 1,253,075.1 Euros to 3,650,827.8 Euros. We added the geospatial allocation of willingness to pay according to five landscape quality categories. Our approach could be used to identify priority areas for conservation based on maximizing landscape value, and would be useful in detecting interesting or conflict areas associated with new management and planning alternatives. In this sense, this approach offers managers to seek territorial management strategies to increase economic efficiency in the allocation of resources.  相似文献   
56.
安邦河湿地是一个典型的寒区湿地,本文运用功能群的方法对其浮游植物季节变化进行研究,并运用多元分析方法分析其与环境因子的关系.安邦河湿地共有浮游植物种8门104种,划分为14个功能群,分别是C、D、E、F、H1、J、Lo、M、MP、N、P、SN、X1和Y.其中重要功能群是C、D、E、J、Lo、N、P和Y.浮游植物的功能群组成季节变化明显,春季以功能群E和Lo生物量所占比例最大,分别为27.45%和20.49%;夏季以功能群D、J、P占优,为28.59%、18.53%和19.47%;秋季以功能群J、P为主,占39.65%和13.34%.可见,安邦河湿地浮游植物功能群的季节变化呈现为E+Lo→D+J+P→J+P的特点,反映了水环境特征:春季低水温低营养盐、夏季高水温高营养盐且水体混浊、秋季水温和营养盐均较高.运用冗余分析(RDA)分析浮游植物功能群与环境因子之间的关系,结果显示水温(WT)、无机氮(DIN)和溶解性磷酸盐(SRP)是安邦河湿地浮游植物功能群季节变化的主要环境因子.  相似文献   
57.
Cavitational reactors are a novel and promising form of multiphase reactors, based on the principle of release of large magnitude of energy due to the violent collapse of the cavities. An overview of cavitational reactors in the specific area of water disinfection, in terms of the basic mechanism, different reactor designs including recommendations for optimum operating parameters and applicability of the cavitation phenomena for disinfection of different micro-organisms have been presented. A design of a pilot scale sonochemical reactor has been presented, which forms the basis for development of industrial scale reactors. Economic analysis for comparison of cavitation phenomena with other conventional techniques of disinfection has been discussed. It appears that though cavitation is quite successful in treatment of water at laboratory scale operations, comparatively higher cost of treatment as compared to the conventional chemical methods is a hindrance in its industrial scale application. Intensification of cavitational activity and efficient design of industrial scale hydrodynamic cavitation reactors is required for ensuring successful application of cavitational reactors at industrial scale operation.  相似文献   
58.
集成膜法除盐系统具有连续产水、出水质量好、易控制、占地少、不需酸碱、利于环保等优点。文章通过对集成膜法水处理技术进行研究与应用,将原有的化学除盐水处理方式改为集成膜法水处理工艺,该方法产水水质高且水质稳定,每年可节约酸碱200 t,阴、阳离子交换树脂10 t,切实解决电厂所面临的产水水质不稳定、酸碱废液排放等问题,有力推动了清洁生产。  相似文献   
59.
乙醇对含水层中燃油芳香烃内在生物修复的潜在风险   总被引:1,自引:0,他引:1  
内在生物修复,是在没有工程措施促进的情况下利用土著微生物降解含水层内灾害性物质的一种修复技术,在燃油烃污染管理方面具有显著的成本效益。该技术需要确定自然衰减过程,并能够继续提供有效的风险保护。针对燃油污染含水层,北美与欧洲认为内在生物修复是值得优先考虑的应用技术。然而,随着乙醇燃油的推广使用,我国在应用这样的经验时需要考虑乙醇的潜在影响。现有的文献研究表明乙醇存在能够阻止燃油主要污染物芳香烃(BTEX)的生物降解,降低水环境的pH值,并可能增强BTEX在水中的溶解性,或存在对生物的毒性,或因为乙醇降解降低介质的渗透性能。因此,需要更好地认识乙醇的潜在风险,为发展乙醇燃油污染含水层修复策略提供科学依据。  相似文献   
60.
Molecular techniques and modelling are presented as powerful tools required in the performance of efficient soil and water bioremediation systems. An Escherichia coli CC118-D strain was constructed by inserting the Klebsiella pneumoniae hpa B gene, coding for the unstable 3,4-dihydroxyphenylacetate 2,3-dioxygenase, into its chromosome. When the constructed strain was immobilized, both enzyme stability and viability increased along the studied period, in absence of antibiotic. We proposed this strategy as an approach to overcoming plasmid instability and to enhance enzyme activity and stability, avoiding antibiotic utilization. A model was developed to understand and predict the behaviour of bacteria and pollutants in a bioreactor system, considering: fluid dynamics, molecular/cellular scale processes and biofilm formation.  相似文献   
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