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1.
ABSTRACT: A modified version of the U.S. Environmental Protection Agency's QUAL-II water quality simulation model is calibrated and applied to the Lower Winooski River, Vermont. The river flows through the metropolitan Burlington area and is impacted by several industrial and municipal point sources and by operation of hydropower facilities. Several structural modifications are made in the model to improve water quality simulations in rivers impacted by algal growth; these include the addition of organic nitrogen and organic phosphorus compartments and provision for algal uptake of ammonia and/or nitrate nitrogen. The model is interfaced with statistical programs which facilitate tabulation, display, and analysis of observed and predicted concentrations. The model is calibrated and tested against data from two intensive water quality surveys. Applications demonstrate the factors controlling water quality and sensitivities to point source waste management strategies and flow, as influenced by hydropower operations.  相似文献   

2.
ABSTRACT: Economic benefit functions of water resource use are estimated for all major offstream and instream uses of Colorado River water. Specific benefit estimates are developed for numerous agricultural regions, for municipal uses, and for cooling water in thermal energy generation. Economic benefits of hydropower generation are given, as are those for recreation on Colorado River reservoirs and on one free-flowing reach. Marginal and total benefit estimates for Colorado River water use are provided. The estimates presented here represent a synthesis of previous work, providing in total a comprehensive set of economic demand functions for competing uses of Colorado River water. Non-use values (e.g., benefits of preserving endangered species) are not estimated.  相似文献   

3.
In developing countries, large dam projects continue to be launched, primarily to secure a time-stable freshwater supply and to generate hydropower. Meanwhile, calls for environmentally sustainable development put pressure on the dam-building industry to integrate ecological concerns in project planning and decision-making. Such integration requires environmental impact statements (EISs) that can communicate the societal implications of the ecological effects in terms that are understandable and useful to planners and decision-makers. The purpose of this study is to develop a basic framework for assessing the societal implications of the river ecological effects expected of a proposed large dam project. The aim is to facilitate a comparison of desired and potential undesired effects on-site and downstream. The study involves two main tasks: to identify key river goods and services that a river system may provide, and to analyze how the implementation of a large dam project may alter the on-site capacity and downstream potentials to derive river goods and services from the river system. Three river goods and six river services are identified. River goods are defined as extractable partly man-made products and river services as naturally sustained processes. By four main types of flow manipulations, a large dam project improves the on-site capacity to derive desired river goods, but simultaneously threatens the provision of desirable river goods and services downstream. However, by adjusting the site, design, and operational schedule of the proposed dam project, undesirable effects on river goods and services can be minimized.  相似文献   

4.
Effective river management requires integration of biophysical and human dimensions of the ecosystem, which in turn involves the development of new forms of decision-making processes and institutional frameworks. In New South Wales, institutional changes to river management have been formalized in the Water Management Act 2000. This paper presents the findings of a case study that investigated decision-making processes in the establishment of environmental flow regimes for the Lachlan River in western New South Wales. The study was based on document analysis, observation and interviews with members and support staff of a stakeholder-based river management committee. The findings of the study highlight social capital, adaptive management and consensus decision making as key components in establishing environmental flow regimes as part of a participatory approach to river management.  相似文献   

5.
ABSTRACT: Texas river authorities are a type of large, regional water district that must be financially self-sufficient. An institutional and historical study of Texas river authorities reveals the broad power of these organizations and their influence in water management. River authorities now control 25 percent of surface water deliveries in Texas. Over two-thirds of authority water was developed by river authorities; nearly one-third was purchased from private or public ventures. While river authority activities have been effective where these services are marketable, the provision of public good services is limited. Increased visibility of these organizations is paralleled by challenges to their traditional autonomy.  相似文献   

6.
谢意 《四川环境》2021,(2):198-203
河长制作为一种综合管理制度,明确了河湖治理的权利和责任,实现了外部性的内化与交易费用的降低,河长制的起源是内生性变化的结果,其制度变迁的过程受制于路径依赖的惯性及其所处的社会环境变化,河湖水质的改善和水治理能力现代化的提升验证了河长制是制度创新的成功实践。中国河湖治理制度的演进符合制度变迁的进程,河长制的实施是历史的必然选择。基于制度变迁理论,以首创河长制的江苏省为例,通过展开江苏省河湖治理政策的演变过程分析河长制的成效和实施动因,进而总结制度变迁理论为河长制变迁提供的启示。  相似文献   

7.
ABSTRACT: The Montana Department of Natural Resources and Conservation developed a hydrologic model to help analyze the effects of allocating water for consumptive and instream uses in the upper Missouri River basin of Montana. The model, a PC-based FORTRAN program, uses a mass-balance approach to compute monthly streamflows, reservoir operations, hydropower production, and irrigation and municipal water uses throughout the 54,000 square mile basin for a 59-year base period. Simulation results are presented as monthly mean and percentile-exceedence values. The model was run for baseline conditions and six hypothetical water-allocation alternatives. Results were used by staff resource area specialists to assess potential impacts to water quantity and distribution, water rights, water quality, stream channel form, fisheries, wildlife, recreation, hydropower production, and economics. These analyses were presented to the public and the decision-making board in an environmental impact statement (EIS). Though, in many instances, the model did not allow for detailed, site-specific analyses, the model was an important tool and its simulation results formed the hydrologic basis for the EIS.  相似文献   

8.
Abstract: Recent water sector reforms and increased scarcity and vulnerability of water resources, combined with declining public funding available for large scale infrastructure investment in the sector, have led to a greater awareness by the Government of Vietnam for the need to analyze water resource allocation and use in an integrated fashion, at the basin scale, and from a perspective of economic efficiency. In this study we focus on the development, application, and selected policy analyses using an integrated economic hydrologic river basin model for the Dong Nai River Basin in southern Vietnam. The model framework depicts the sectoral structure and location of water users (agriculture, industry, hydropower, domestic, and the environment) and the institutions for water allocation in the basin. Water benefit functions are developed for the major water uses subject to physical limitations and to constraints of system control and policy. Based on this modeling framework, we will analyze policies that can affect water allocation and use at the basin level, including both basin-specific and general macroeconomic policies.  相似文献   

9.
徐文贤 《四川环境》2007,26(6):63-68
采用现场调查监测,并结合收集的水电、渔业等方面资料,对闽江上游渔塘溪支流上的布上、碧州、马坪三级电站开发对植被、水土保持、水生植物、浮游生物、底栖动物、鱼类、水质的影响作了分析。结果表明,电站开发造成库区污染严重、富营养化、河段断流并产生一定的不利影响等。提出其环境减缓补救措施及今后闽江支流梯级电站开发生态环境保护的防治措施。  相似文献   

10.
ABSTRACT: In 1976–77, benthic invertebrates were sampled at four sites in a 410-kilometer reach of the lower Mississippi River to define the communities in the river and to determine differences between communities upstream and downstream from the industrial and municipal complexes of Baton Rouge and New Orleans, Louisiana. The most common and most numerous organisms collected were Corbicula and tubificid worms. The benthic community structure of the lower Mississippi River is influenced by substrate type and stability, channel geometry, river velocity, vegetation and organic detritus, and salinity. Sampling stations near the left and right banks had low velocities, and substrate types ranged from medium silt to very fine sand. Burrowing organisms such as tubificids, chironomids, and ephemerid-type mayflies dominated these environments. At the center, left-center, and right-center stations, velocities were higher and substrate materials were coarser than at the bank stations; only Corbicula was present in large numbers. Near the river mouth, salinity and aquatic vegetation greatly affect the benthic community structure. Differences in benthic community structure in the Mississippi River are due primarily to different hydrologic conditions. Industrial and municipal wastes discharged into the river appear to have little or no widespread effects on benthic populations.  相似文献   

11.
ABSTRACT: The Pawtuxet River flows from a relatively rural area through some of the more highly industrialized sections of Rhode Island. During its journey, the river receives many municipal, industrial, and ground water sources of metal constituents. The present report is the first in a two part series in which the water quality of this urban river was evaluated by a chemical monitoring study of the sources, transport mechanisms, and fate of cadmium, chromium, copper, lead, and nickel in the river. The second paper will use the chemical data to derive and calibrate a steady-state water quality model for this river. The metal concentrations In the river tended to increase from the headwaters to the mouth with river stations nearest to point source outfalls showing elevated values. In some sections of the river, levels of a few of the metals could not be explained by the point sources; and other inputs, including sediment resuspension, axe proposed to make up this apparent unbalance. The ability of a municipal secondary treatment plant to remove metals was demonstrated, and the tie-in of the effluent from a major chemical company to the plant did not cause any observable deterioration in treatment efficiency.  相似文献   

12.
ABSTRACT: The tri‐state river basins, shared by Georgia, Alabama, and Florida, are being modeled by the U.S. Fish and Wildlife Service and the U.S. Army Corps of Engineers to help facilitate agreement in an acrimonious water dispute among these different state governments. Modeling of such basin reservoir operations requires parallel understanding of several river system components: hydropower production, flood control, municipal and industrial water use, navigation, and reservoir fisheries requirements. The Delphi method, using repetitive surveying of experts, was applied to determine fisheries' water and lake‐level requirements on 25 reservoirs in these interstate basins. The Delphi technique allowed the needs and requirements of fish populations to be brought into the modeling effort on equal footing with other water supply and demand components. When the subject matter is concisely defined and limited, this technique can rapidly assess expert opinion on any natural resource issue, and even move expert opinion toward greater agreement.  相似文献   

13.
尼洋河流域水资源十分丰富,水能蕴藏量巨大,生态环境良好。随着西藏经济的发展,必将出现大规模开发利用水资源的趋势,探讨流域水资源和环境的现状及可持续发展具有十分重要的现实意义。本文对尼洋河流域基础资料的收集与整理,分析尼洋河流域的特点与现存的问题,根据收集的水质监测资料,分析了流域污染源概况和构成,以未进行水环境功能区划为前提,选择模糊综合评价法对尼洋河流域水环境质量进行现状评价,并对超标断面进行了原因分析,通过对2012年尼洋河流域14个监测断面监测成果的评价,得出尼洋河流域水质现状良好的结论,为以后的水功能区划分、水质目标的确定以及水环境功能区划分提供依据。  相似文献   

14.
流域开发对环境的累积影响日渐受到关注。文中以西藏巴河流域水电开发为例,从累积影响环境因素的指标层和指标分析入手,提出运用AHP对累积影响程度进行估算,初步研究发现:巴河流域水电梯级开发必须建立在生态系统的稳定和土地、森林、草地资源适度开发及合理规划布局的基础上,才能实现水资源的高效开发利用。  相似文献   

15.
本文通过分析岷江上游水电梯级开发对生态环境的主要影响,确定维持流域生态平衡的最小生态环境需水量测算方法。经测算,岷江上游的生态环境需水量占流域多年平均流量的6%~33%,越靠近源头,生态环境需水量所占比例越大。建议提高岷江上游生态环境需水量所占比例,将生态环境需水占比超过20%的茂县以上河段设为禁止开发区域,取消禁止开发区域内原规划的6级电站。同时在已建电站坝下和各县域出境断面设置生态流量监控断面,确保流域开发的环境生态平衡。  相似文献   

16.
River managers are aware that river restoration entails addressing and effectively solving wicked social-ecological problems. Contemporary river corridor management is characterized by a variety of actors with different perspectives and interests, and by complex institutional settings and legal landscapes. Additionally, at the intersection between litho-, hydro-, and biological fields, new research suggests that river restoration should reactivate matter and energy fluxes, re-establish spatial connections with the floodplains, and enhance aquatic and terrestrial habitats without exacerbating flood risk. First, we outline a general structure of participatory river corridor management that addresses the following key requirements: (1) unambiguous, participatory spatial delineation of the river corridor; (2) comprehensive assessment of the river corridor's hydro-geomorphological, ecological, socio-economic and cultural processes; (3) transparency and consistency of the decision-making process; as well as (4) a coherent envisioning process. Subsequently, we present an overview of two river corridor management processes, conducted in South Tyrol, Italy. Specifically, we analysed the Etsch/Adige River corridor between Laas/Lasa and Glurns/Glorenza in the Upper Vinschgau/Venosta valley characterized by intense agricultural land use and the densely populated Eisack/Isarco River corridor in Brixen/Bressanone. Based on structured interviews with project managers, we highlight strengths and shortcomings of the proposed participatory management and envisage procedural improvements.  相似文献   

17.
乌江干流梯级电站生态调度现状分析   总被引:2,自引:0,他引:2  
乌江是我国十三大水电基地之一,主要的开发任务为发电,其次为航运,兼顾防洪及其他。本研究在乌江干流上选取了4个具有代表性的断面,运用修正的Tennant法和综合法计算了维持乌江干流各代表性河段基本健康所需的生态需水量。研究表明,目前乌江干流梯级电站采取的调度措施能够满足各代表性河段所需的最小生态需水量。但目前的调度措施仍是建立在发电效益最大化基础上的,未能从干流生态环境系统的特殊要求进行调度,给干流生态环境造成了一定影响。本文最后提出了从多方面开展乌江干流梯级电站生态调度研究工作的建议。  相似文献   

18.
Population growth in the Southeast has driven withdrawals for municipal water beyond the limits of local supplies. With few options left for development of virgin sources, a number of urban areas are looking toward demand management and additional supplies by reallocating storage in reservoirs that were built primarily or in part for hydropower. Hydropower has become a lesser part of the mix of energy sources, and the question arises as to value of water for that purpose relative to its value for municipal use. Three cases are used to examine the issue. Effects of withdrawal for municipal water supply on output of electric energy are estimated. Benefits of foregone energy are evaluated using the least cost alternative for replacement, and benefits for municipal water are estimated using costs for development of new sources. Benefits for use as municipal water are found to be considerably higher than benefits for hydroelectric energy at existing prices, even higher than the least cost alternative for replacement. Given the spatial distribution of the cases, that finding would appear to hold in general across the region.  相似文献   

19.
The Brisbane River serves multiple functions in both its upper catchment and its lower reaches. The lower reaches are highly urbanized where the river flows through Australia's third largest city, and here the river sustains transport activities, waste water disposal, a port, and both motorized recreation and active and passive non-motorized recreation. In the city the river also serves as a locality for community events, as a cultural icon and as a residential neighbour. Many of these functions are spatially and temporally congruent and, amongst other issues, this congruency has the potential to generate significant levels of noise conflict. This paper describes the approach adopted to assess the nature and extent of noise conflicts and to develop a comprehensive strategy of noise management-allas part of a larger scheme for an integrated approach to manage the Brisbane River and its catchment. Noise management strategies recommended for implementation include noise zoning of the river, planning and approval processes for land-based waterway facilities, noise planning and approval processes for residential and other noise-sensitive uses, codes of practice for rowing and similar activities, as well as the more conventional approach of regulatory limits on river-based noise sources. The paper demonstrates that a wide range of strategies are necessary to handle complex pollution problems of this sort, and provides a model of comprehensive action for management of noise from river-related activities that may find application elsewhere.  相似文献   

20.
ABSTRACT: In this paper we seek to identify historical indicators of international freshwater conflict and cooperation and to create a framework to identify and evaluate international river basins at potential risk for future conflict. We derived biophysical, socioeco‐nomic, and geopolitical variables at multiple spatial and temporal scales from GIS datasets of international basins and associated countries, and we tested these variables against a database of historical incidents of international water related cooperation and conflict from 1948 to 1999. International relations over freshwater resources were overwhelmingly cooperative and covered a wide range of issues, including water quantity, water quality, joint management, and hydropower. Conflictive relations tended to center on quantity and infrastructure. No single indicator—including climate, water stress, government type, and dependence on water for agriculture or energy—explained conflict/cooperation over water. Even indicators showing a significant correlation with water conflict, such as high population density, low per capita GDP, and overall unfriendly international relations, explained only a small percentage of data variability. The most promising sets of indicators for water conflict were those associated with rapid or extreme physical or institutional change within a basin (e.g., large dams or internationalization of a basin) and the key role of institutional mechanisms, such as freshwater treaties, in mitigating such conflict.  相似文献   

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