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Coastal change and hypoxia in the northern Gulf of Mexico：Part I
Committee on Environment and Natural Resources Mississippi/Atchafalaya River Basin
2009/5/6
The Committee on Environment and Natural Resources (CENR) has identified the input of nutrient-rich water from the Mississippi/Atchafalaya River Basin (MARB) as the prime cause of hypoxia in the north...
Generalisation of physical habitat-discharge relationships
Physical Habitat Simulation river ecosystem health river flows
2009/5/6
Physical habitat is increasingly used worldwide as a measure of river ecosystem health when assessing changes to river flows, such as those caused by abstraction. The major drawback with this approac...
Identification of stakeholder perspectives on future flood management in the Rhine basin using Q methodology
stakeholder perspectives Rhine basin future flood management
2009/5/4
This article identifies different stakeholder perspectives on future flood management in the downstream parts of the Rhine basin in Germany and The Netherlands. The perspectives were identified using ...
HYDROGEIOS：a semi-distributed GIS-based hydrological model for modified river basins
river basins hydrological cycle hydrological model
2009/5/4
The HYDROGEIOS modelling framework represents the main processes of the hydrological cycle in heavily modified catchments, with decision-depended abstractions and interactions between surface and grou...
Floodplain sediment from a 100-year-recurrence flood in 2005 of the Ping River in northern Thailand
Floodplain sediment Ping River 100-year-recurrence flood
2009/5/4
The tropical storm, floodwater, and the floodplain-sediment layer of a 100-year recurrence flood are examined to better understand characteristics of large monsoon floods on medium-sized rivers in nor...
Stakeholder discourse and water management–implementation of the participatory model CATCH in a Northern Italian alpine sub-catchment
Water Framework Directive alpine sub-catchment Northern Italian
2009/4/28
The Water Framework Directive (WFD, directive 2000/60/EC) was created to ensure the sustainable use of water resources in the European Union. A central guideline included throughout the directive is a...
Detecting changes in extreme precipitation and extreme streamflow in the Dongjiang River Basin in southern China
extreme streamflow Dongjiang River Basin southern China
2009/4/28
Extreme hydro-meteorological events have become the focus of more and more studies in the last decade. Due to the complexity of the spatial pattern of changes in precipitation processes, it is still h...
Comparison of Artificial Intelligence Techniques for river flow forecasting
Artificial Neural Network Adaptive Neuro Fuzzy Inference System Generalized Regression Neural Networks
2009/4/28
The use of Artificial Intelligence methods is becoming increasingly common in the modeling and forecasting of hydrological and water resource processes. In this study, applicability of Adaptive Neuro ...
风浪作用下太湖悬浮态颗粒物中磷的动态释放估算
磷释放 太湖
2009/3/19
用振荡试验方法模拟了不同风速对太湖沉积物扰动产生的悬浮颗粒物(SPM)量, 研究了SPM中磷的物化形态转化和生物矿化衰减过程, 定量估算了动力扰动作用下, SPM中磷转化对太湖磷负荷贡献. 结果表明: SPM中以物化形态转化为可溶性活性磷(SRP)为主的释磷作用对太湖水体磷负荷的贡献为0.44 t/a, 因生物矿化作用为主的磷衰减对水体磷负荷的贡献量约425.8 t/a, 占太湖外源入湖总量的1...
黄河中游植被恢复对流域侵蚀产沙的影响与治理前景
植被恢复 黄河中游
2009/3/4
根据黄土高原不同自然带水环境和侵蚀环境的特点, 研究了黄河中游不同自然带植被类型的变化、林、草的分布界线及植被的恢复能力. 年降雨量530mm是黄河中游林、草分布的临界年降雨量. 在影响流域产沙的地带性、非地带性环境要素中, 悬移质泥沙中径(D50,mm)、林木覆盖率(V,%)起主要作用, 其中, 林木覆盖率(V,%)对流域产沙的影响权重仅小于泥沙中径(D50,mm)作用的3.4%, 近乎相等. ...
黄土高原地区侵蚀产沙的尺度效应研究初探
黄土高原 侵蚀产沙 尺度效应 产沙模数
2009/3/4
以黄河流域水文站的观测数据为基础, 对黄土高原地区产沙模数的尺度效应进行了分区研究. 研究表明, 不同分区的黄土、风沙、基岩的空间分布与组合关系不同、地形(坡度)不同, 其产沙模数随流域面积变化的趋势也不相同, 可以分为单调减小、单调增大、先增大而后减小、先减小而后增大等类型. 在对数据进行双对数转换后, 对上述尺度效应关系进行了线性和二次函数的拟合, 并分别针对这两种函数形式给出了校正方程. 依...
基于环境同位素技术的怀沙河流域地表水和地下水转化关系研究
环境同位素 水化学 补给 相互作用
2009/3/4
地表水和地下水是流域水循环的重要组成部分, 流域内地表水和地下水之间的相互作用历来是流域水循环研究的关键环节. 环境同位素和水化学作为水循环研究中的示踪剂, 可以有效地揭示流域内地表水和地下水之间的转化关系. 在对位于北京市怀柔区的怀沙河流域进行现场调查并对泉水、河水和井水采样进行氢氧稳定同位素和水化学组成测定的基础上, 分析了流域内沿河道不同部位的泉水、河水和井水的氢氧稳定同位素和水化学组成的空...
基于区域ET结构的黄河流域土壤水资源消耗效用研究
土壤水资源 蒸发蒸腾(ET) 消耗效用 黄河流域
2009/3/4
文中依据水资源的特性, 对土壤水资源做了重新定义. 并结合其动态转化关系, 以消耗项—蒸发蒸腾(ET)为基础, 剖析了土壤水资源的消耗结构和效用. 将区域土壤水资源的消耗效用分解为3部分: 高效消耗(植被蒸腾消耗)、低效消耗(植被的部分棵间蒸发)和无效消耗(裸地和植被的部分棵间蒸发). 此外, 按照是否参与生产, 又将高效消耗和低效消耗作为生产性消耗, 无效消耗由于其参与水循环而被认为是非生产性消...
利用GRACE空间重力测量监测长江流域水储量的季节性变化
GRACE 水储量 长江流域
2009/3/3
2002年3月成功发射的美德合作重力卫星计划GRACE(Gravity Recovery And Climate Experiment)已经开始提供阶次数达到120、时间分辨率为约1个月的地球重力场模型时变序列. GRACE的星座由两颗相距约220 km, 高度保持300~500 km, 而倾角保持约90°的近极轨卫星组成. 由于采用星载GPS和非保守力加速度计等高精度定轨技术以及高精度的星-星跟...