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ZHOU Gang-yan 《水利水电快报》2007,28(5):5-8
This note compares institutional arrangements for water resources management in two river basins,namely,those of the Susquehanna River in the United States and the Yangtze River in China.The Susquehanna River Basin Commission is composed of the US federal government and the three states of New York,Pennsylvania,and Maryland through which the Susquehanna River passes.Under the authority of the Susquehanna River Basin Compact,the Commission deals with water resources problems throughout its vast drainage area.In contrast,the Changjiang(Yangtze River) Water Resources Commission(CWRC) lacks relative effectiveness in mobilizing provincial governments in transboundary water resources management. 相似文献
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A Modeling System for the Evaluation of Water Resources Management Strategies in Thessaly,Greece 总被引:4,自引:2,他引:4
A modeling system was developed to evaluate the sustainability of water resources management strategies in the two major basins
of Thessaly Region in Greece, namely the Pinios River and the Lake Karla basins. The intense and extensive agriculture of
water demanding crops, such as cotton, and the absence of reasonable water resources management have lead to a remarkable
water demand increase, which is usually fulfilled by the over-exploitation of groundwater resources. This unsustainable practice
has deteriorated the already disturbed water balance and accelerated water resources degradation. The modeling system consists
of a hydrological model, a reservoir operation model and methods for the estimation of water demands. The study area was sub-divided
into sub-basins and water balance analyses were performed for each sub-basin and each control node of the system for a number
of water resources management strategies. Four strategies of hydro-technical project development were coupled with two strategies
of groundwater withdrawal and three water demand strategies. In total, more than 24 water management strategies were evaluated.
The results showed that, under the existing water resources management, the water deficit of the Pinios River and Lake Karla
basins is very large. However, the development of proposed hydro-technical projects in the Pinios River basin coupled with
water demand management measures, like improvement of existing water distribution systems, change of irrigation methods, and
changes of crop cultivation could alleviate the problem and lead to sustainable and ecological use of water resources in the
study area. 相似文献
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水资源承载力作为评价地区水资源安全与否的一个基本度量,其理论与应用研究意义重大。根据DPSIR框架展开水资源承载力因子分析,得到一个4层递阶结构的指标初选框架,并构建了一套全面的水资源承载力指标体系。以汉江流域为例,采用层次分析-模糊综合评价法(AHP-Fuzzy)展开水资源承载力评价与预测。分析结果表明不调水情况下,江汉流域3级分区中,丹江口以上分区水资源承载力优于其他2分区;实施调水后,各分区水资源承载力受跨流域调水的影响而发生变化,均可认为已达到基本可承载状态。 相似文献
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Combining Population Growth Model and Generalized Additive Model to Determine Optimal Water Level FOR Waterbird Conservation: A Case Study of Siberian Crane (Leucogeranus Leucogeranus) in Lake Poyang,China 下载免费PDF全文
Siberian crane (Leucogeranus leucogeranus) is one of the most endangered species in the world. The ecological integrity of its main wintering ground at Poyang Lake in China is crucial for the future of the species because Poyang Lake accommodates 99% of its global population. With the Three Gorges Dam fully operational, science‐based adaptive strategies are urgently needed to avoid catastrophic ecological consequences. This study quantified the link between water level variation and population growth rate of the Siberian crane in Poyang Lake using a suite of advanced statistical techniques. We first used the stochastic Gompert growth model within the state space modelling (SSM) framework to infer population growth rate, density dependence, and process variability and observation errors. We then applied generalized additive models (GAMs) to the population growth rate to quantify the effects of environmental stochasticity. Our SSM results indicated that there was little support for density dependence, and environmental stochasticity was the main forcing for Siberian crane population variations in Poyang Lake. Although the SSM suggested that water levels in both high‐ and low‐water seasons were important factors for Siberian crane population, inference on their effects were elusive because of large confidence intervals of the estimated coefficients. Using GAM, we confirmed the non‐linear effects of water level on population growth rate. Based on the modelled response curves, we proposed the optimal water level for Siberian crane conservation: (a) maximum summer water season level should be less than 19.5 m and (b) minimum winter water level should be between 8.7–10.2 m. Our methods of integrating population dynamic model and GAM have wide relevance for regional biological conversation efforts that seek to maintain a resilient population of threatened species. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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基于离散Hopfield神经网络联想记忆特性,建立了湖库富营养化等级综合评价模型,对全国24个湖库进行富营养化等级综合评价,并与文献投影寻踪法、评分指标法和LM-BP网络法的评价结果进行比较。结果表明:①离散Hopfield神经网络运用于湖库营养化等级评价具有简单、直观,容易实现等优点,其评价结果令人满意;②一般离散Hopfield神经网络并非适用于任何富营养化等级评价,当评价对象单项指标(因子)间存在较大差异时,对象将得不到正确的评价。 相似文献