浅谈平原河网地区防洪系统的调度

根据太湖流域防洪调度实际情况,对其气象信息、实时水位及其特征值等水情信息和实时工情分析,进行防洪形势分析。按照太湖流域防洪调度规则,进防洪调度的仿真计算,形成供决策者参考的调度方案。     

二元驱动的河湖历史演变及其启示

以河湖历史演变过程为研究对象,分析了演变的驱动力及其作用特征、影响因素,提出河湖演变呈现出由自然-人工二元平行驱动向二元交错驱动发展的趋势。针对在人为改变河湖水系的历史过程中曾出现过的问题和风险,重点讨论了当前水系布局规划需要思考的问题,包括自然地理分异、气候变化、成本效益、生态环境等。建议拓展研究的维度和尺度,合理利用自然情势并关注人类活动潜在而深远的影响,多途径削减不利影响,以构建满足水资源合理配置、兴利除害、生态环境保护等社会需求的江河湖库水系格局。     

苏北平原河网区典型农村中小河流水体氮磷赋存特征

以苏北平原河网区的盐城市射阳县某个典型圩区(面积12.73km2)为例,通过连续15个月对圩区内沟渠河流水体采样分析,研究苏北平原河网区中小河流地表水氮磷赋存特征。结果表明:研究区域中小河流水体氮磷超标严重,水体处于富营养化状态。所有水样品总氮质量浓度均超过GB 3838—2002《地表水Ⅲ类水质标准》(ρ=1.0 mg/L),79%的总氮质量浓度超过Ⅴ类水质标准(ρ=2.0 mg/L);73%的总磷质量浓度超过Ⅲ类水体标准(ρ=0.2 mg/L),39%的样品超过Ⅴ类水质标准。地表水氮素和磷素主要以溶解态形式存在;硝态氮是溶解态总氮主要赋存形态,相应的比例约为60%,铵态氮比例最少,约为10%;溶解态活性磷是溶解态磷素主要赋存形态,约为80%。畜禽养殖相对集中区域地表水氮素和磷素浓度高于其他区域;中沟、干渠等小型河流水体在夏季存在水质分层现象。     

城市河湖水质改善与保障技术研究

西北地区干旱少雨造成的水资源紧张及水环境恶化,已成为中国西部大开发中水环境治理的难题.本研究结合陕西省渭河宝鸡市区段生态治理工程,分析了生态治理工程对宝鸡市区河湖水质的影响,并在市区人工湖浅水区进行了芦苇带对湖水和渭河公园中湿地对河水水质改善效果的试验研究.试验结果表明,芦苇带和湿地对城市河流水质改善效果良好.根据实地调查和试验结果,提出宝鸡市在治理工程后的进一步改进措施,分析了在市区河湖进行生态修复的可行性.为城市河湖的水环境系统修复提供科学依据.     

黄河冲淤特性"相对清水冲刷、相对浑水淤积"

本文回顾总结了以往对黄河干支流河道冲淤特性的研究情况 ,利用所提出的冲淤临界流量与含沙量的关系与渭河下游、黄河下游进行了对比。以此为基础 ,勾画出了黄河干支流冲积河道“相对清水冲刷、相对浑水淤积”的物理图景 ,提出了多沙河流“相对清水冲刷、相对浑水淤积”的冲淤特性     

横石水治理方案实施过程中存在问题思考

横石水治理工程治理方案从设计到实施过程中，不但要符合中小河流的治理理念原则，在实施中，还要从施工措施、当地的具体情况和群众要求等多方面思考对治理方案合理的优化与调整，工程施工才能顺利开展和实施，治理后的河流满足当地管理和行洪要求。     

郊居离学背景下乡镇小学学生通学出行特征研究——以南京市江宁区秣陵中心小学为例

在城乡统筹背景下,“撤点并校”政策的落实使得乡镇中心学校学生居住地与上学地距离较远——“郊居离学、通学难”现象日益突出。本研究以南京市江宁区秣陵乡镇中心小学为调研对象,在统计分析学生居住地—上学地空间分布、通学出行特征等综合信息基础上,对远距离上学学生的主导交通方式——校车的路线、通学时间、出行需求及意愿进行了剖析,并对校车与其他各出行方式的上学优劣势进行了比较。最后根据凋研结果,提出了优化学生通学出行方式的相应战略与措施,提高了乡镇学生就学可达性。     

城市轨道交通物业开发模式浅析——以重庆为例

通过与深圳、香港、纽约、东京等国内外城市轨道交通物业开发模式的比较,对重庆轨道交通物业开发现状进行了剖析,归纳出轨道交通物业开发的四种模式,即站点零散空间开发模式、上盖物业一体化开发模式、开发圈层化模式和新城TOD开发模式,为后续轨道交通物业开发建设提供参考。     

Application of the Stream Evolution Model to a Volcanically Disturbed River: The North Fork Toutle River,Washington State,USA

In this study, a recently revised version of the channel evolution model, named the Stream Evolution Model (SEM), was applied to the upper North Fork Toutle River disrupted by the deposition of a 2.5‐km³ debris avalanche during the catastrophic eruption of Mount St. Helens in 1980. The results show that, in the first few years following the eruption, upstream channel reaches generally incised, evolving in SEM Stage 4 (i.e. degradation and widening), while downstream reaches aggraded, evolving in Stage 5 (i.e. aggradation and widening). However, starting in the late‐1980s, this simple pattern was disrupted by incision in the downstream reaches, which seemed to propagate upstream. Since the 1990s, lateral channel adjustments have become predominant as rates of vertical adjustment have slowed and river valley top widths relaxed to asymptotic values. Spatial and temporal sequences of channel evolution have tended to follow the sequences of stages expected according to the SEM, although these sequences have been frequently disrupted by renewed incision, secondary cycles of adjustment and the impacts of local geologic, geomorphic and hydraulic conditions. Within the quasi‐full SEM cycles, stages 4 and 5 were sometimes repeated, while stage 6 (quasi‐equilibrium) was sometimes omitted, and stage 8 (anabranching) only occurred in the downstream braided/anabranching reaches. According to the SEM, degradation, widening and lateral activity (stages 4 and 7) are forecast to continue until transverse valley profiles and channel planforms stabilize and floodplain and terrace surfaces are fully colonized by vegetation. Copyright © 2017 John Wiley & Sons, Ltd.     

Sharing Rivers for Peace,Development, and Security

Abstract

Water is a finite resource, and with the considerable upsurge in population, urbanization, and industrialization, it is also becoming an increasingly scarce resource. Many countries in the world rely on river waters, and many of those rivers are shared by two or more countries. Dams on those rivers have been a major source of tensions, disputes, and, in some cases, even conflict between riparian countries because dams could result in massive diversion of river flows. Those developments have, inter alia, highlighted the relevance and importance of the principles of international water law, as reflected in the United Nations Convention on the Law of the Non-Navigational Uses of International Watercourses. The World Commission on Dams has also underscored the importance of, and elaborated on, those principles with regard to dams on shared rivers. This article discusses and analyzes the recommendations of the Commission in this area, and compares them with the principles of international water law as enunciated in the United Nations Convention