黑土区地埂设计方法综述

地埂是黑土区坡耕地防治水土流失经常采用的一种技术措施,主要适用于地面坡度不大,坡面较长,土层较厚,水土流失较轻的坡耕地。修筑地埂能拦截分散地表径流,降低径流能量,防止坡耕地土壤冲刷,比较有效地防止耕地漫垄面蚀和断垄出沟的问题。它的特点是:工程量小,就地取材,占地少,投资小,施工简单。根据地埂的作用,在设计中应做到:一是要使地表径流尽量拦截就地入渗或缓解能量分散排出;二是要使径流不至于对土壤产生冲刷或少量的冲刷,应通过地埂拦截淤积在田块内。因此,地埂设计的关键因素是确定合理的地埂间距(田面宽度),以保证田面不产生水土流失。     

二龙山农场水土流失治理措施

1　水土流失现状二龙山农场水土流失面积为1 22×104hm2,占耕地总面积的45.31%,水土流失以水蚀(沟蚀)和风蚀为主。一分场漫岗地小流域,春天干旱刮大风,耕地土壤被刮走,产生风蚀;沟蚀多发生在岗坡地及两岗之间的低洼水线。水土流失产生23条冲刷沟,类型以低洼水线冲刷沟为主,总长     

生态袋措施在海西天然气管网二期管道工程中的应用

生态袋措施是工程措施和植物措施相结合的方法,将生态袋措施在海西天然气管网二期管道水工保护工程中进行推广使用,现场实践表明,采用生态袋措施可有效地控制坡面水土流失、防止管沟覆土冲刷和保持坡体稳定,起到保护管道安全和控制水土流失的双重作用。文章介绍了生态袋措施的特点、施工工艺以及工程应用成果。     

水土流失过程及防治措施之浅见

当前,我省水土流失治理工作已经迈进到讲科学、讲技术、讲效益的新时期。在防治上应当既讲究宏观效益,又讲究微观效益。因此,努力探索水土流失的演变规律及其防治措施的效益问题,有着十分重要的意义。水土流失这种水流土动,土随水跑的基本自然现象,实际是土壤颗粒在水冲刷力作用下,产生的位移。每个具体的土壤颗粒,受三种力的作用:一     

兴凯湖水土保护问题及对策

兴凯湖由于受到边境河岸冲刷、水土流失严重、湖岗植被恢复较慢、水体也受到一定污染。文章提出应采取白棱河和松阿察河整治工程,加快流域水土流失治理速度,恢复湖岗植被,防治水污染,加强保护区建设,推进土地整理等措施,有效保护兴凯湖地区原始生态环境和水土资源。     

赵光农场水土流失治理项目建设经验及效果

黑龙江省赵光农场属于丘陵漫岗地区,水土流失比较严重。坡耕地面积为2.33万hm2,占耕地总面积的77.81%,农场耕地水土流失面积2 733 hm2,占总耕地面积的9.14%。水土流失量1 352万t/hm2,冲刷沟约有260余条,长达37 km。为加强水土流失治理,促进赵光农场生态修复,采取了一系列措施,把水土保持工...     

巩固治理成果 充分发挥效益

九三垦区水土保持工作取得一定成效,总结出治理水土流失的“冲刷沟治理技术研究”和“黑土浸岗水土流失综合防治模式研究”两项成果。本文介绍了垦区治理现关，并就巩固治理成果、措施与方法、提高治理效益方面提出看法。     

大广高速立交工程水土流失预测

近年来的大规模工程建设以及对运行多年的病险工程的加固维修使得大面积的土地被扰动,再加上强降雨的冲刷,产生严重的水土流失。随着大广高速新蔡西互通式立交新建工程项目的开工建设,地表被扰动,土层遭到破坏,造成人为新增水土流失,给建设区及周边生态环境带来影响和危害。若不及时采取有效的水土保持综合防治措施,将造成较大的水土流失和生态环境破坏,因此根据主体工程的布局及施工工艺,科学合理地预测工程建设造成的水土流失量,客观评价水土流失的危害,以便为水土流失防治分区、分区防治措施合理设计、施工进度安排及水土保持监测方案编制提供依据。     

东大沟地区水土流失现状及防治对策

1水土流失现状 东大沟地区位于黑龙江省东部，完达山西北麓，因东大沟河而得名。根据实地调查，该地区水土流失面积217．63时，占土地总面积的46．8％，水土流失给当地带来了很大的危害。土壤侵蚀以面蚀为主，已形成冲刷沟38条，总长37．08km，沟壑密度0．17km/km^2。冲刷沟尚不稳定并有发展的趋势，冲刷沟可分为低洼水线冲刷沟和工程冲刷沟两种。     

植物措施防治排水渠道冲刷的应用

植物措施是防治地面坡度较大的排水渠道未修建跌水前冲刷的一种有效方法,可较大幅度减缓渠道冲刷速度,提高渠道的完好程度,减少水土流失。     

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.     

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。     

2003年兰考、东明洪水漫滩落淤情况调查

通过对2003年秋汛期间兰考北滩、东明南滩两处漫滩情况进行调查与分析，得出的结论为：滩区共滞蓄水量6亿～9亿m^3，漫滩落淤范围为7．5km^2，顺漫滩水流方向的落淤距离约3km。在这种水沙条件下，泥沙不能被输送至较远的堤河。经分析计算，本次泥沙落淤量为900万～1350万t，且距口门1．0km范围内落淤泥沙中的82％为粒径大于0．05mm的粗沙。由此得到的主要认识有：①靠自然落淤解决“二级悬河”问题非常困难，甚至会增大“二级悬河”程度；②给漫滩水预留出路是降低淹没损失的关键；③落淤的粗沙使土地产生了十分严重的沙化现象，并且使当地环境趋于恶化。     

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。     

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.     

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.