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1.
拉哈渠首枢纽是黑龙江省嫩江干流上的一个重要的无坝引水工程, 近年来由于渠首江道的演变已严重影响引水。为此, 采用动床河工模型进行了较为深入地研究, 解决了模拟宽滩河道和在缺乏实测资料的情况下模拟推移质运动等技术难点, 揭示渠首河道的演变规律, 在大量方案试验的基础上, 提出了整治措施。  相似文献   

2.
赣江南昌段东西河分流处河床演变与航道整治   总被引:3,自引:0,他引:3  
赣江是长江水系中的第二大支流,它发源于闽赣交界的武夷山区,其主支流-西支在永修县吴城镇注入鄱阳湖,再经量子湖口入长江。介绍了赣江尾闾地区南昌段的水系特点和水文泥沙基本情况,对1987-1992年四级航道整治后南昌段东西河分流处的河床演变进行了分析,并探讨了其变化的原因,着重分析了东西河分流比随上游来流量而变化的原因和对策;对赣江主航道-西河进口的两个浅滩的变化进行了分析。赣江南昌至吴城段河西宽阔,比降平缓,来水量丰富,含沙量很小,具有发展水运的优越条件,赣江南昌-湖口航道整治成为三级航道是安全有可能的。  相似文献   

3.
This study applies the concept of integrated water resources management (IWRM) to a river basin in Iran, and in so doing, proposes a framework for implementing IWRM principles. Issues such as stakeholder participation, sustainability in several subdomains, scenario analysis, dispute resolution, climate change and well-designed models have been considered. Through a river basin simulation model (RIBASIM) and sustainability criteria, stakeholders made decisions for improving the level of sustainability in the basin. The result of decision making for the future was tested under climate change impacts, and the outputs showed serious challenges, so a strategy is proposed for overcoming these impact effects.  相似文献   

4.
This article deals with river channel conditions before and after a rare flood event. The characteristics of five cross‐sections before the flood are described and compared with post‐flood conditions. Hydraulic and flow data for the pre‐ and post‐flood channel are presented. It is maintained that the land adjoining the new channel can be developed if certain precautionary measures are taken.  相似文献   

5.
城市河流作为城市的重要组成部分,对城市经济发展、市民安居有着巨大影响,但相当一部分城市河流或河段因遭受重污染,黑臭问题严重。河流治理领域自19世纪至今已有长足发展,治理理念从单纯的"水利工程治理"到"近自然河道治理工程"再向"基于流域管理的治理"转变。基于流域尺度的河流治理是复杂的系统工程,包括多方面内容,以凉水河流域为例加以阐述,其治理技术包含了高品质再生水处理技术、河道污水口除臭技术、促流净水技术和河坡植生增绿技术等。  相似文献   

6.
At the end of the last century, the shorelines of the Lower River Rhône were embanked and submersible dikes were built in the main channel, delimiting dike fields. We compared the morphological, hydrological and sedimentary variables of nine dike fields, four sites in dead arms and one in the main channel, in order to describe the fluviosedimentary functioning and to produce a classification of these different natural and engineered backwaters. Within these ‘artificial floodplains’, the different types of backwaters and their long-term changes bear a strong similarity to those observed within a natural floodplain. The long-term frequency of submersion by the water of the main river channel is the first factor that controls the erosion and sedimentation within the different backwaters. Three types of site can be distinguished: the lotic sites are the main channel and one dike field, five dike fields comprise the semi-lotic sites and the cluster lentic sites include the three remaining dike fields and the four dead arms sites. These three groups also differ in their riparian habitats and in their juvenile fish assemblages. As juvenile fish were most abundant in the semi-lotic dike fields, the use of such structures can be envisaged in order to restore high fish diversity in rivers where the former floodplain has disappeared or is no longer accessible to fish because of human modifications. © 1997 John Wiley & Sons, Ltd.  相似文献   

7.
8.
A framework for characteristics identification and source apportionment of water pollution in the Jinjiang River of China was proposed in this study for evaluation. A total of 114 water samples which were generated between May 2009 and September 2010 at 13 sites were collected and analysed. First, support vector machine (SVM) and water quality pollutant index (WQPI) were used for water quality comprehensive evaluation and identifying characteristic contaminants. Later, factor analysis with nonnegative constraints (FA-NNC) was employed for source apportionment. Finally, multi-linear regression of the absolute principal component score (APCS/MLR) was applied to further estimate source contributions for each characteristic contaminant. The results indicated that the water quality of the Jinjiang River was mainly at the third level (65.79%) based on national surface water quality permissible standards in China. Ammonia nitrogen, total phosphorus, mercury, iron and manganese were identified as characteristic contaminants. Source apportionment results showed that industrial activities (63.16%), agricultural non-point source (16.50%) and domestic sewage (12.85%) were the main anthropogenic pollution sources which were influencing the water quality of Jinjiang River. This proposed method provided a helpful framework for conducting water pollution management in aquatic environment.  相似文献   

9.
唐迎洲  徐贵泉 《中国水利》2014,(5):49-51,53
平原感潮河网地区极易遭受流域洪水、区域暴雨、台风、高潮等多重袭击影响,防汛情况复杂,通过开展防汛减灾能力评价可以科学反映地区抵御水灾的能力。以上海市为例,建立了上海市防汛减灾能力评价指标体系,共分3个层级、2个一级指标、7个二级指标、27个三级指标,以期对其他相关地区防汛减灾能力评价体系的建立提供借鉴。  相似文献   

10.
The Saint‐Sauveur dam was built in 1992 in the middle section of the Buëch River. Downstream of the dam, a channel incision by several meters was observed. A gravel replenishment operation was planned in order to restore the active channel. An equivalent of two times the mean annual bedload‐transport capacity (43,500 m3) was replenished downstream of the dam in September 2016. The aim of this paper is to quantify morphological change associated with sediment remobilization in order to evaluate the efficiency of the restoration works. The monitoring was based on a combination of (a) change detection using sequential high‐resolution digital elevation models (from airborne LiDAR data), (b) bedload tracing using active ultrahigh‐frequency radio‐frequency identification technology, and (c) complementary field surveys of channel grain‐size distribution and morphology for bedload‐transport computation. Field monitoring allows us to capture a net aggradation along a 2‐km reach after the first post‐replenishment flood. A sediment balance analysis was performed to back‐calculate bedload supply coming from the sluicing operation during the flood. Although the sediment replenishment operation clearly had a positive impact on the morphological conditions of the starved river reach, the effective bedload supply from artificial berms (22,650 m3) was insufficient to initiate substantial channel shifting along the restored reach and a subsequent amplification of the sediment recharge. The combination of high‐resolution topographic resurveys and sediment tracing was successful to evaluate the downstream propagation of sediment replenishment effects.  相似文献   

11.
ABSTRACT

This article assesses the main problems facing the Spanish Tagus River basin, and the management that has caused (or allowed) them. It examines the economic, social, environmental and political-institutional dimensions of Tagus River management in terms of sustainable development. We find that the institutions responsible for designing and implementing water policy in the Tagus basin have been unsuccessful in balancing the three classic dimensions of sustainability, resulting in systematic and recurrent failure to comply with the European Water Framework Directive and the principles of sustainable development.  相似文献   

12.
Restoration of regulated rivers presents fundamental challenges because of the complexity and adaptive nature of riverine ecosystems. It is now agreed that restoration strategies need to restore the system as a whole (structure, function and dynamics). Most studies are faced with the same difficulties concerning the right scale for restoration actions, the representative attributes of the riverine system and the measures capable of surveying restoration action impacts. This work proposes an approach to river restoration borrowed from the conceptual and theoretical background of landscape ecology. Leaning on experience on biodiversity restoration along the Lower Seine river, we propose a systemic approach based on the hierarchical nature of riverine systems. This approach suggests that like any system, riverine ecosystems can be simplified into basic units which are complementary and integrated in a hierarchical structure. Simplification leads to focusing on one component of the ecosystem at a relevant scale of space and time (organization level). Here, we focus on two attributes of this ecosystem at different scales: community organization and landscape organization. These organization measures, realized at different observation scales, provide insight to the ecological response of the system in time. They are measures of the stability of the system and can provide effective tools for predicting or following the impact of restoration actions on riverine landscapes. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

13.
为了分析三峡水库的调洪运用对长江中下游干流水位的影响,采用成熟的预报模型对2010年7月中下旬长江上游地区发生的大洪水过程进行还原计算,分析了三峡水库的拦洪削峰作用.结果表明,洪水过程中,通过对三峡水库的合理调度,有效降低了长江中下游干流各站水位,其中宜昌-沙市河段水位降低约2.5 m,城陵矾-汉口河段水位降低约1.0 m,九江-大通河段水位降低0.3-0.5 m,沙市水位降到警戒水位以下,缓解了荆江河段和中下游干流的防洪压力,缩短了监利-汉口河段各站超警戒水位时间.  相似文献   

14.
The identification of adequate wastewater treatment for small communities is a complex problem since it demands a combination of data from different sources, such as aspects of the community and landscape, the receiving environment and the available wastewater treatment technologies. The Catalan Water Agency (Agència Catalana de l'Aigua) considered using an EDSS (Environmental Decision Support System) as a tool to help water managers select the most adequate treatment for the urban wastewater of nearly 3,500 small communities in Catalonia (Spain). From that moment, EDSS was applied to all the river basins in Catalonia. In this paper the authors present the results obtained for the 76 small communities located in one of these river basins: the Fluvia River Basin. The characteristics of the community used in the reasoning process of the EDSS, the list of selected wastewater treatment alternatives, the technical environmental justification for the selected treatments and the reasons for discarding, favouring or disadvantaging them are presented. Finally, some results for the Fluvia River Basin are compared with those obtained in other Catalan river basins with different characteristics in order to evaluate which are the significant features in identifying adequate wastewater treatments.  相似文献   

15.
分布式侵蚀产沙模型是土壤侵蚀模型的重要发展方向,本研究将蛇家沟流域下垫面划分为5 ×5m的栅格,每个栅格内赋予相应的高程、坡度、地貌、土地利用等属性信息.根据流域DEM,确定流域的汇流方向、流路与汇流累积面积.在蛇家沟流域内采用“穷举算法”对SCS-CN模型的参数值进行校正.基于DEM、地貌、土地利用以及降雨等资料,利用黄土丘陵沟壑区良好的水沙关系,运用VB.NET+ARC ENGINE9.2+ SQLSERVER2000构建分布式侵蚀产沙模型.模型结构简单,输入参数比较少,利用求产流来求产沙,考虑了土地利用、汇流等因素具有一定的物理意义,并能达到一定的预报精度.其中产沙模型是建立在黄土丘陵沟壑区普遍的水沙关系基础上,通过校正水沙关系式系数及产流模型中的CN、λ值可在其它相似的小流域内使用.该研究可为黄土丘陵沟壑区水土保持治理效果评价提供依据.  相似文献   

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