黄河河南段"二级悬河"现状分析

利用大量翔实的实测资料,对黄河河南段“二级悬河”的现状进行了系统分析,指出：河南段已有280km长的河段形成“二级悬河”,占河段总长的60％,其中以东坝头一伟那里河段最为突出;最大滩槽高差为1．67m,滩唇高出堤脚最大为6．04m;滩面横比降最大达3．04‰,是河道纵比降0．18‰的16．9倍。同时,为确保黄河安澜,缓解“槽高、滩低、堤根洼”的“二级悬河”不利局面,应积极采取有效措施,加快“二级悬河”治理工作步伐。     

黄河下游漫滩洪水调控模式研究

针对漫滩洪水特性提出了改善黄河下游“二级悬河”的方案,应用动床模型试验对改善方案进行了模拟研究。结果显示：控制漫滩可以有效的减缓“二级悬河”的发展,加大主槽累计冲刷量,减小滩区淹没面积及改善河道横比降。如果黄河下游遭遇大漫滩洪水,可以在控制漫滩条件下排放最大洪峰流量不超过10 000 m3/s的过程洪水。     

对于黄河下游治理方略的几点建议

二级悬河是黄河下游防洪的心腹之患，必须改变当前槽高滩低的局面，消除二级悬河，才能使黄河下游成为一条有健康生命的河流。只有通过废除生产堤，才能利用大自然的力量，较快、较好地消除二级悬河的严峻现状。要废除生产堤，首先要搞好滩区的安全建设。在此前提下，建议改变小浪底水库的运用方式：拦蓄大洪水，不拦蓄中小洪水；排泄浑水，不排泄清水；汛期水库少量蓄水，做到拦粗排细；允许洪水漫滩，实现漫滩刷槽，利用滩地处理大部分来沙。     

黄河濮阳河段二级悬河状况及治理措施

河南黄河濮阳河段经多年建设，堤防、河道、滩区安全等工程体系初步形成，但因黄河泥沙淤积的问题没有得到有效解决，“槽高、滩低、堤根洼”的二级悬河状况仍在加剧，防洪形势十分严峻。通过对黄河濮阳河段的二级悬河现状进行介绍，分析了形成二级悬河的原因，提出了“以防洪为主，统筹兼顾”的治理原则，在此基础上提出了继续适时进行调水凋沙、淤滩、淤筑堤河等治理二级悬河的措施。     

三门峡水库“拦粗排细”的分析

三门峡水库自１９６０年至１９６６年为蓄水运用和滞洪排沙运用，受壅水作用，流速锐减，粗泥沙淤而泥沙排出库外，有“拦粗排细”作用。随着库区淤积发展，潼关以下库区形成高滩深槽，一般洪水不漫滩，较大洪水漫滩时，较细泥沙被水流带到地落淤。     

河道生产堤对洪水影响的二维数值模拟研究

河道主槽两侧修建的生产堤影响滩槽泥沙横向交换,对河床演变带来很大影响。本文针对黄河下游游荡型河段的现实状况,采用平面二维水沙数学模型按现状生产堤、废除生产堤、限制生产堤三种条件进行了典型洪水的模拟,模拟计算给出了夹河滩-高村河段不同边界洪水演进、漫滩的过程及滩区淹没程度。作者分析了三种不同边界条件对洪水水位、河段流速、滩槽冲淤的影响,表明废除生产堤使洪水提前进滩,与现状生产堤状态相比大大降低了河道洪水位;限制生产堤方案可以适当控制漫滩流量,扩大滩槽泥沙横向交换,改善滩区生产条件。为了维持黄河河槽活力,协调人河关系,抑制二级悬河发展,限制下游河道生产堤治理方案是比较适宜的。     

黄河小北干流连伯滩淤区泥沙运动特点分析

2004年黄河小北干流放淤试验连伯滩淤区落淤结果显示：①淤区进口含沙量越大、泥沙粒径越粗，淤区含沙量衰减量、粒径降低值越大，落淤效果越好；②淤区“淤粗”、“排细”呈明显的反比例关系，适当减小粗沙落淤率，能够显著增大细沙排出量和落淤泥沙粒径。从试验结果看，将细沙排出率控制在70％、粗沙落淤率控制在85％左右是比较适合的。     

河南黄河滩区综合治理与开发措施探讨

从分析河南黄河滩区治理开发现状及存在问题入手，提出综合治理开发措施：实行移民建镇与集中避洪相结合，解决滩区群众安全问题；采取挖河淤滩等多种措施，改善“二级悬河”形势；加快河道整治，有效控制河势，固维护堤；大力开展滩区水利建设，改善滩区的生产条件；调整滩区产业结构，以市场为导向，实行农、牧、渔及生态旅游等综合开发，促进经济发展。     

2012年宁蒙河段洪水特点及对河道的影响

利用实测资料分析了2012年黄河上游洪水的水沙特点和洪水演进、传播特性以及洪水对河道冲淤的影响,结果表明:2012年黄河上游洪水水量大、沙量小、漫滩严重,洪水传播速度慢,洪水峰型沿程有所改变;洪水期河道冲淤调整剧烈,整个宁蒙河段河槽冲刷1.916亿t,滩地淤积量达2.032亿t,冲刷以中粗沙为主。洪水对河道排洪能力的恢复作用显著,洪水后内蒙古河段代表水文站同流量水位下降0.43~0.63 m,平滩流量增大了201~588 m3/s。漫滩洪水对宁蒙河段河槽的塑造作用较大,建议充分利用大漫滩洪水维持宁蒙河道的长期排洪排凌能力。     

黄河下游二级悬河段河势及漫滩模型分析

结合实体模型试验,在洪量和沙量不变的情况下,对概化处理后不同量级洪水条件下黄河下游二级悬河段的水沙过程进行了研究。结果表明:随着洪峰流量加大,进入滩区的水量也随之增大,其漫滩范围和落淤厚度有逐步增大的趋势,但漫滩洪水基本流路无大的变化;漫滩洪水的水流交换模式包括在三角形滩区内完成的淤滩刷槽交换模式和水流漫滩后通过较长距离条形滩区落淤后回归主槽的交换模式。     

山西省地下水资源开发利用中存在的问题及对策

山西省水资源严重短缺 ,地下水超采严重。分析了地下水资源量及可开采量、地下水开发利用历史和现状 ,以及超采产生的环境地质问题。在此基础上 ,提出了缓解地下水超采、有效合理开发利用地下水的一些措施意见 ,为加强地下水保护和管理提供了科学依据。     

雷州半岛地区2015年防旱抗旱工作对策与启示

2015年,广东省雷州半岛地区出现大范围干旱,该文总结了干旱特点,分析了干旱成因,采取了水资源统筹调配、引导调整种植结构及播种时机、人工增雨、筹措资金应急补助等抗旱措施,效果较好。此外,提出该地区今后打造"扩库硬渠上井群"升级版、推进农业结构调整、改善生态环境推动绿色发展的防旱工作对策。     

Operation and Maintenance Performance and Conflicts in Flood-control Projects in Bangladesh

Many embankments failed in severe floods in Bangladesh in 1987 and 1988, and concern grew over ways to improve flood-control projects. Maintenance was poor due to reliance on periodic rehabilitation, but few failures were due to poor construction or maintenance. Embankments mostly failed where they were eroded or were deliberately cut. They were cut by people living outside who believed they were made more flood-prone, and by people living inside because of internal drainage congestion. This reflected inadequate hydrological modelling, lack of consultation and failure to resolve conflicts between affected groups. Resources for maintenance are not generated locally and could be used more efficiently. Participatory planning could reduce conflicts, encourage a sense of project ownership and facilitate contributions to maintenance.     

南京市2016年暴雨洪水分析与思考

2016年汛期,南京市发生了建国以来的大洪水,降雨量和主要河湖水位均超历史.在对2016年暴雨、水情、洪水特点分析的基础上,提出加强南京市防洪工程体系的建议.     

Domestic Water and Sanitation in Cyclones and Floods in Bangladesh and a Proposed Research Agenda

ABSTRACT

Water is one of the top priority item s i relief activities but the appropriateness and effectiveness of this activity may be questioned. Water and sanitation (WS) are inseparable and together they play major roles in the transmission of the pathogen of diarrhoeal disease. Thousands of people die or suffer from WS-related diseases during postdisaster periods. Here we present WS-related experiences gained after Bangladesh's 1991 cyclone and the views of participants in a regional and a national (local) workshop on this matter held in Bangladesh. About 63 per cent of the water purifying tablets (WPTs) distributed after the 1991 cyclone were found to have lost potency Relief personnel lack basic knowledge about WS practices and the management of WS provision. Participants in the two workshops documented serious problems i this field at both regional and national levels. Major issues for research may include: an appropriate environmental preparedness plan; appropriate waste disposal technologies; appropriate water treatment methods; self- help activities during vulnerable periods; and health education related to WS in disaster situations.     

Progress in ecological and environmental water requirements research and applications in China

Abstract:

With economic development, as well as population growth, the conflict between water supply and demand has become more and more acute in China, and it has been aggravated further by the irrational utilization of water resources. As a result, the deterioration and destruction of the eco‐environment have become increasingly serious. In order to effectively protect ecosystems and improve their ecological conditions, many studies on ecological and environmental water requirements (EEWR) have been carried out in China. In this paper, the concept and characteristics of EEWR are addressed, and the main advances of EEWR research and applications in China are summarized in four types of systems including studies on rivers, vegetation, lakes and wetlands, and groundwater. In conclusion, issues necessary to be studied further in the future are put forward.     

我国灌区建设及管理技术发展成就与展望

新中国成立70年来,我国灌区建设与管理取得了举世瞩目的成就,农田灌溉面积由1949年的1593万hm2发展到2016年的6714万hm2,位列世界第一,保障了我国粮食安全供给和社会经济发展。我国灌区建设与管理已经历了三个大的发展阶段,依靠科技进步解决了发展过程中出现的各种问题,使我国灌区建设与管理水平逐步得以提升。今后的30年将是我国实现灌区现代化的时期。本文较系统介绍了我国灌区发展概况、灌区建设与管理技术进展和成就、灌区面临的主要问题和挑战、以及灌区现代化发展展望。     

衡水市地下水开发利用存在的问题及对策

通过对衡水市地下水开发中存在问题的客观分析,提出了今后开发、利用和保护地下水的措施.     

Distribution and removal of Giardia and Cryptosporidium in water supplies in Germany

This study has been conducted, to estimate the distribution of Giardia and Cryptosporidium in German water supplies and the removal efficiency of surface water treatment plants for Giardia and Cryptosporidium by conventional treatment. Water samples from six surface water treatment plants in different parts of Germany were simoultaneously examined for Giardia and Cryptosporidium. Investigations for both parasites were carried out in the period from July 1993 until December 1995. The results confirmed the occurrence of Giardia and Cryptosporidium in surface and raw water, to intermediate steps after treatment, in back wash water, in the first filtrate and in final water. Giardia or Cryptosporidium or both have been found in 76.2% of the investigated raw water sources. The average number of the detected Giardia cysts was 88.2/100 1 (max.1314/100 I), and the average number of Cryptosporidium oocysts was 116/100 I (max. 1081/1001). In the intermediate steps (including flocculation and several steps of filtration), Giardia or Cryptosporidium or both have been found in 33.3% (50/150) of the samples. 14.9% of drinking water samples (7/47) were positive for Giardia (max. 16.8 /1001) and 29.8% (14/47) were positive for Cryptosporidium (max. 20.8/100 I). Overall, Giardia and Cryptosporidium, or both were detected in 38.3% of the drinking water samples. The parasites have been found in nearly all of the investigated backwash water samples. The filtrate of a rapid sand filter was analysed immediately after filter backwashing during the ripening period of the filter. Good elimination results were obtained by optimizing relevant water treatment process, but a low flocculant dose following sudden variation in the raw water quality, causes a breakthrough of Cryptosporidium into the treated water. Although water treatment technologies are effective to remove Giardia and Cryptosporidium, the results clearly show that Giardia and Cryptosporidium evade the filter harries m the absence of visible treatment deficiencies and low turbitidy level, and contaminate final water.