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311.
水资源短缺和水污染是我国面临的重要环境问题.受流域自然整体性和流动性的影响,某一行政区的污染通常可以通过水体向另一个或多个行政区转移.传统理论上,人们认为造成跨行政区流域水污染治理困境的主要原因是经济增长方式、产业结构、环境执法效率和管理体制的障碍.实际上,以上因素难以从根本上解释跨行政区流域水污染的治理困境.文章运用博弈理论对流域污染治理中中央政府和地方政府之间的信号传递博弈,以及流域上下游地方政府之间的污染治理博弈进行了分析,结果表明:在区域利益、信息不对称和缺乏激励机制的影响下,地方政府很难真正履行中央政府的治理政策,而污染外部性和利益冲突则使各行政区之间难以达成合作治理,府际博弈的非理性均衡成为跨行政区流域水污染治理困境的深层次原因.鉴于此,跨行政区流域水污染治理必须理解政府的角色和行为,才能找到有效的治理对策.中央政府有必要增强政策威胁的置信度,提高监督和惩治水平,克服地方政府和污染企业达成利益同盟,并通过重复博弈建立行政区之间的流域合作治理机制. 相似文献
312.
土地利用/覆被变化是生态环境演变最重要的因素之一,其研究对于促进区域生态经济协调发展有重要意义。根据1976年和2006年玛纳斯河流域两期遥感影像资料,基于生态经济学的最新方法采用卫星遥感技术以及Costanza等的生态系统服务价值评价手段,对期间玛纳斯河流域生态服务系统服务功能价值变化进行分析研究。结果表明:①玛纳斯流域土地利用结构变化在30年间表现为草地、林地、不断减少,而耕地、水域、沙地和建设用地不断增加,反映出人类因素及生态环境恶化的趋势;②该流域生态系统服务功能价值总额由1976年123.831 08元减少至2006年101.521 08元。减幅:18.02%,年均减少0.741 08元,通过对玛纳斯河流域生态系统服务功能价值进行评价,为玛纳斯河流域生态开发和治理,以及环境整治提供决策依据。 相似文献
313.
Linyan Zhang Hong Jiang Xiaohua Wei Qiuan Zhu Shirong Liu Pengsen Sun Jingtao Liu 《Journal of the American Water Resources Association》2008,44(5):1154-1163
Abstract: Information on evapotranspiration (ET) can help us understand water balance, particularly in forested watersheds. Previous studies in China show that ET was relatively low (30‐40% of total precipitation) in the Minjiang Valley located in the upper reach of the Yangtze River Basin. However, this conclusion was derived from research on small‐scale watersheds (<100 km2). The objective of this paper was to present ET information on meso‐scale watersheds in the Minjiang Valley. Four meso‐scale watersheds (1,700‐5,600 km2) located in the Minjiang Valley were used to estimate ET using the water balance approach. We first generated forest vegetation variables (coniferous forest percentage, forest cover percentage, and derived forest vegetation index) using remote sensing data. Landsat 5 TM satellite images, acquired on June 26, 1994, were selected for the vegetation classification. Actual annual ET was calculated based on 11‐year estimated precipitation and measured streamflow data (1992‐2002). We also calculated potential ET (PET) using an improved Thornthwaite model for all four watersheds for the period of 1992‐1998. PET can provide additional information about potential capacity of water flux to atmosphere in the region. Seasonal (dry and rainy) PET and ET for all studied watersheds were also estimated for comparison purposes as the water balance approach, at shorter than annual scales, would likely provide inaccurate estimates of ET. The dominant vegetations in the Minjiang Valley were grasslands, conifer forests, and shrub‐lands. Our results confirmed that both ET and PET for three studied meso‐scale watersheds in the Minjiang Valley is relatively low (39.5‐43.8 and 28.2‐47.7% for ET and PET, respectively), with an exception of ET in the Yuzixi watershed being 71.1%. This result is generally consistent with previous research at small watershed scales. Furthermore, the low ET across various scales in the Minjiang Valley may be related to the unique deeply cut valley environment. 相似文献
314.
本文对《清史稿·河渠志》及《清史稿·灾异志》中有关淮河流域的水灾资料进行了系统的整理和分析,从中可以窥出清代淮河流域水灾规律之大概。 相似文献
315.
316.
提出了防洪安全评价的概念,建立了防洪安全评价指标体系;提出利用熵值法确定指标权重,采用多层次模糊优选评价模型对防洪安全进行评价;以辽宁省辽河流域为例,对不同历史时期防洪安全状况进行了比较,结果与实际相符。 相似文献
317.
Emerging approaches to water resources development and management typically highlight equity and productivity as two main objectives. In the context of integrated water resources management within a river basin, managers and stakeholders often need a comparative assessment of different options for water augmentation and/or allocation. Pitting such options against predefined objectives, such as equity and productivity, requires an assessment of the effects that available options will have on these objectives. Available documentation indicates that not only does the interpretation of such objectives vary widely, but also the available methods for assessing equity and productivity run into significant limitations in the availability of adequate data. This limitation has largely kept decision makers from gaining a comprehensive overview of equity and productivity scenarios, whether within or across sectors, that could facilitate better‐informed decisions. To address this methodological gap, this article scrutinizes different notions associated with equity and water productivity, and limitations in prevalent assessment methods with the view to develop and demonstrate pragmatic methodologies for assessing equity and productivity in data‐scarce contexts. The discussion and findings are based on a review of relevant literature and empirical and consultative research work in the Olifants River basin in South Africa. The demonstrated methodologies for assessing equity and productivity, besides being useful in data‐scarce contexts, are insightful for initiating several policy measures and also for exploring the relationship between equity and water productivity. 相似文献
318.
Yusuf M. Mohamoud Rajbir S. Parmar 《Journal of the American Water Resources Association》2006,42(3):755-768
ABSTRACT: Methods to estimate streamflow and channel hydraulic geometry were developed for unpaged streams in the Mid‐Atlantic Region. Observed mean annual streamflow and associated hydraulic geometry data from 75 gaging stations in the Appalachian Plateau, the Ridge and Valley, and the Piedmont Physiographic Provinces of the Mid‐Atlantic Region were used to develop a set of power functions that relate streamflow to drainage area and hydraulic geometry to streamflow. For all three physiographic provinces, drainage area explained 95 to 98 percent of the variance in mean annual streamflow. Relationships between mean annual streamflow and water surface width and mean flow depth had coefficients of determination that ranged from R2= 0.55 to R2= 0.91, but the coefficient of determination between mean flow velocity and mean annual streamflow was lower (R2= 0.44 to R2= 0.54). The advantages of using the regional regression models to estimate streamflow over a conceptual model or a water balance model are its ease of application and reduced input data needs. The prediction of the regression equations were tested with data collected as part of the U.S. Environmental Protection Agency (USEPA) Environmental Monitoring and Assessment Program (EMAP). In addition, equations to transfer streamflow from gaged to ungaged streams are presented. 相似文献
319.
Edwin D. Bailey 《Journal of the American Water Resources Association》1979,15(3):801-811
ABSTRACT: The Tucson area is totally dependent on ground water, which is in increasingly short supply due to excessive overdrafts. Tucson area waste water treatment plants discharge material quantities of secondary effluent downstream, which is lost to evapotranspiration and recharge of the ground water basin. The city and the four large mining companies who share the common Santa Cruz basin ground water, recognized the common water supply problem and agreed to fund a feasibility study for mining process use of the effluent to partly alleviate the overdraft of ground water. The study analyzed the projected waste water effluent resources, potential mining company demand for waste water effluent and possible interface of an effluent delivery facility with the proposed Central Arizona Project. The effluent resources were analyzed with respect to potential demand. An optimum alignment was selected. An optimum system was detailed through design schematics, amortized cost and finance requirements, and an implementation schedule. It was concluded that a waste water effluent delivery facility could be implemented which would utilize reclaimed effluent in quantities approximating 35 percent of basin overdraft and which would provide revenue for full cost recovery over a 20 year operation period. The mining companies are studying the internal economic impacts of the project. 相似文献
320.
流域水质目标管理技术研究(Ⅳ)——控制单元的水污染物排放限值与削减技术评估 总被引:11,自引:3,他引:8
对国内外流域水污染物排放限值与削减技术评估体系进行了归纳,系统介绍了美国和欧盟水污染物排放限值与削减技术评估体系的框架和特点,指出其对我国流域水污染物排放限值与削减技术评估体系建设的借鉴意义.以水质保护目标为前提,按照“分区、分类、分级、分期”的理念,建立了流域控制单元水污染物排放限值与削减技术评估体系,阐述了该体系的内涵和特点;探讨了控制单元各类污染源的水污染物削减技术评估和最佳可行技术,削减技术评估指标、方法和程序,污染物削减技术检测平台,污染物排放限值确定等关键问题. 相似文献