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1.
河湖水系连通特征及其利弊   总被引:9,自引:0,他引:9  
随着水资源以及水环境健康的恶化,河湖水系连通性作为河流健康以及提高水资源利用的一个重要指标在国家"十二五"战略规划中被着重提出。目前,中国对河湖水系连通特征及其对河流健康的影响缺乏足够的认识,本文主要对河湖水系连通的定义、分类、评判指标、影响因素及其对水环境健康的影响进行了一一阐述。分析表明:维持水系连通可以明显地改善...  相似文献   

2.
河西黑河(弱水)水系的变迁   总被引:4,自引:0,他引:4  
冯绳武 《地理研究》1988,7(1):18-26
中更新世晚期以来黑河流量逐渐减少,由外流河变为内流河,由统一水系变为各自的独立水系,中、下游由地面水和地下水相互转化,不少河道随流量变化及新构造运动影响而改道,从而沿岸新老绿洲互不相连。  相似文献   

3.
The Irtysh River Basin refers to a water conservation area and a vital ecological barrier in Xinjiang and also partially in Central Asia. Here, the technical solution for the ecological protection and the restoration of the Mountains-Rivers-Forests-Farmlands-Lakes-Grasslands system (MRFFLGs) pilot project in the Irtysh River Basin is refined, by complying with the core concept, i.e., “mountains, rivers, forests, farmlands, lakes and grasslands are a community of life”. The solution stresses the specific characteristics of ecologically protecting and restoring MRFFLGs in the Irtysh River Basin, which aim to reduce ecological water use, soil erosion, forest and grassland degradation, the ecological destruction of mines, water environment pollution and other issues. With overall protection, system restoration, district policy, and problem orientation as the overarching ideas, 162 sub-items of 44 major items with seven categories have been designed and implemented in the project. In addition, some highlights of the management experience that are worth promoting when the pilot project is being implemented are also summarized (e.g., the use of laws to solve historical problems, scientific argumentation and third-party evaluation, proactive guidance for the engagement of people, modern information technology support, and integration with local sustainable development). Lastly, four policy suggestions are proposed: (1) Building a model of systematic protection and restoration by using basins as the basic geographic unit; (2) Establishing and optimizing key weak links of systems and mechanisms; (3) Focusing on remedying the shortcomings of regional talents, technology and capital; and (4) Promoting the MRFFLGs project to integrate “industry, city, people, and tourism” for carrying out a large-scale system project.  相似文献   

4.
新疆的水平循环是,径流形成于山区,流到平原区后不断蒸发和渗漏,最终消耗在沙漠中,或者流入尾闾湖。由于人类活动的影响,水的分布和转化都发生了改变,绿洲中的水量增加,但绿洲以外与河流下游的水量减少,同时有些湖泊缩小甚至干涸,沙漠化发展,自然植被衰退,自然环境退化。  相似文献   

5.
基于河流健康及国际法的跨境水分配关键指标及阈值   总被引:3,自引:2,他引:1  
冯彦  何大明  王文玲 《地理学报》2015,70(1):121-130
基于前期研究中获得的8个河流健康主要评价指标、3个主要跨境水分配指标的结果以及指标之间的相关性,确定了河流健康和跨境水分配的关键指标:多年平均水量、最大取用水量和最小维持水量。跟踪查询《国际淡水条约数据库》内1864-2002年应用3个关键指标的38个国际条约及其所涉及28条国际河流的主要水文信息,通过对条约中水分配指标的标准化计算和分析,得到各指标阈值及其区域性特征:① 最小维持水量指标得到普遍应用,其次是多年平均水量指标,而最大取用水量指标应用率明显低于前两个指标。② 应用多年平均水量指标,在界河上基本确定了平均分配方案,阈值为50%;“内河”属性支流的阈值为100%;跨境河流上产生了较多的差额分配方案和较多的上游国用水多于下游国的方案。③ 最小维持水量指标,其应用有从发达地区向发展中地区扩展、从保证用水向维持生态用水发展的特点;当该指标在跨境和界河的河流尺度上用于保证供水时,该指标阈值平均分别为41.7%和50%,且流域国家实力对其影响极为明显,而在跨境河流河段尺度上阈值平均为36.1%;用于维持河道生态水量时,阈值平均为14.7%,并有逐步增长的趋势。  相似文献   

6.
洪湖湿地恢复中的生态水位控制与江湖联系研究   总被引:6,自引:0,他引:6  
江湖阻隔造成洪湖湿地生态系统呈现出退化态势。维系洪湖湿地生态功能需要一定的水量与适宜的湖泊生态水位。根据洪湖湿地的综合生态功能对湖泊水位的不同要求,确定了洪湖合理的生态水位,以作为科学调度控制水位的重要依据,要建立有机的江湖联系机制,合理而科学地调节洪湖与长江的关系,有利于恢复洪湖湿地生境,保护流域内生物多样性。  相似文献   

7.
人类活动对河湖水系连通的影响评估   总被引:1,自引:1,他引:0  
左其亭  崔国韬 《地理学报》2020,75(7):1483-1493
河湖水系承载着人类赖以生存的水资源,也支撑着经济社会的可持续发展。在自然因素和人类活动双重影响下,河湖水系不断发生着改变,也影响着人类生存和发展。特别是在人类活动日益剧烈的背景下,研究人类活动对河湖水系连通的影响是一个非常重要的科研问题,也是河湖水系连通工程实践的一个关键问题。本文从自然和人工两个方面分析了河湖水系连通的影响因素,阐述了人类活动对河湖水系连通的影响过程,并从河湖水系连通关系、河湖水系功能(自然角度)、河湖水系连通功能(社会角度)三个方面归纳了人类活动的正负面影响;在此基础上,提出了有针对性的影响量化评估方法,便于宏观角度量化和分析人类活动对河湖水系连通的影响。本研究以人类活动剧烈的淮河流域为实例应用,分析了人类活动对淮河水系的影响评价结果。  相似文献   

8.
淮河作为中国7大江河之一,有关其形成时代的研究相对匮乏且存在较大的争议。论文通过梳理淮河流域内已有的研究工作,综合层状地貌面和沉积地层记录探讨了淮河不同河段的形成时代。新生代期间,淮河流域内的水系曾经历2次较大的调整,分别发生在古近纪末和上新世末。古近纪和新近纪期间,淮河流域曾广泛发育湖泊沉积,以河湖相沉积环境为主。而第四纪期间,流域内古地理环境逐渐过渡为以河流相沉积环境为主。现代淮河河湖体系的形成发生在早至中更新世,其后经历不断的演变至今。构造活动和气候变化是驱动淮河流域水系演变的主因。上新世末至早更新世初的青藏运动导致了淮河流域内新近纪水文体系的解体,而晚新生代以来气候的转冷可能是湖泊萎缩、河流作用增强的诱因。  相似文献   

9.
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river re-quirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized. Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that: except Xiliao River is “median”, the rest are all upon “good”, the Dongliao River is even “very good”. The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that: considering “quantity”, except Xiliao River, the rest rivers can all achieve the “quantity” criteria of the en-vironmental flows of river requirements, but if considering the aspect of “quality”, only Dongliao River can reach the “quality” standard. By water quantity-quality combined evalua-tion method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem de-mands.  相似文献   

10.
从区域角度谈江(长江)湖(洪湖)关系的演变,将其划分为江湖一体、逐步阻隔和人为调控3个阶段。详细阐述了江湖关系演变给洪湖湿地带来的不利生态影响。主要表现在:加剧围垦、改变江湖水系格局、加重自然灾害以及土壤潜育化、沼泽化,破坏了江湖复合生态系统平衡。在此基础上,探讨了重建江湖联系的必要性和对策,为长江中游江湖关系治理及生态环境建设提供借鉴与决策支持。  相似文献   

11.
F. Sheldon  M.C. Thoms   《Geomorphology》2006,77(3-4):270
Large rivers are often considered to retain less organic material than smaller streams primarily because of a decrease in retentive structures. From our observations on the Barwon–Darling River, a semi-arid river in southeastern Australia, we suggest that geomorphic complexity plays a fundamental role in the retention of organic matter. The Barwon–Darling River has a ‘complex’ river channel cross-section with large inset benches being a prominent morphological feature within the channel. The importance of geomorphic complexity for retaining organic material is likely to be significant in dryland rivers. These rivers spend extended periods at low flow with infrequent large floods that inundate the floodplain. They do, however, experience more frequent within channel floods that inundate in-channel ‘bench’ features. In-channel geomorphic complexity and its ability to retain organic material, therefore, means that although the dominant lateral movements of organic material will still occur during large overbank flows, smaller ‘pulse’ inputs will occur with each in-channel rise and fall in water level. In dryland rivers, where large overbank flows may only occur every seven or more years, these small ‘pulse’ inputs of organic material may well be vital for the integrity of the system.This paper describes the contemporary complexity of a channel in a regulated and an unregulated reach of the Barwon–Darling and compares this with cross-sections surveyed in 1886. We show that flow regulation has greatly reduced channel complexity. We estimate the potential organic matter input to each bench level within the channel (using data collected under near natural riparian conditions) and measure the contemporary organic loads within the channel of the regulated and unregulated reach. This modelling suggests that the development of water resources has reduced the complexity of the channel in the regulated reach, resulting in a potential decrease in the retention of organic matter in this region of the river. The importance of this organic matter to the aquatic food web of the Barwon–Darling River is also demonstrated.  相似文献   

12.
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed,and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river re-quirements,the efficiency of water resource usage,the consumption coefficient,and the concentration of waste water elimination,the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed,and the criteria for environmental flows of river requirements are established,and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized. Taking the Liaohe River as a model,the environmental flows of river requirements for Xiliao River,Dongliao River,mainstream Liaohe River,Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated,each taking up 39.3%,63.0%,43.9%,43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow,the results show that: except Xiliao River is "median",the rest are all upon "good",the Dongliao River is even "very good". The corresponding results in dualistic water cycle are that,the proportion of natural flows for each river is 57.5%,74.1%,60.8%,60.3% and 60.4%; while the combined evaluation results show that: considering "quantity",except Xiliao River,the rest rivers can all achieve the "quantity" criteria of the en-vironmental flows of river requirements,but if considering the aspect of "quality",only Dongliao River can reach the "quality" standard. By water quantity-quality combined evalua-tion method,only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem de-mands.  相似文献   

13.
邓金运  范少英 《地理学报》2017,72(9):1645-1654
鄱阳湖与长江之间存在着复杂的相互作用关系,决定着江湖水沙交换,对整个区域的水资源、防洪、航运、生态环境等均具有重要影响。本文基于能量的观点,在从新的角度解释鄱阳湖和长江相互作用原理的基础上,构建了江湖相互作用的表征指标—能差Fe,对20世纪50年代以来江湖作用关系变化进行了研究。结果表明,自20世纪50年代以来,Fe值整体呈现增加趋势,说明长江作用减弱,鄱阳湖作用不断增强。三峡水库蓄水运用对江湖关系产生了重要影响,进一步削弱了长江作用。从年内变化来看,由于三峡水库的调节,枯水期长江作用略有增强,汛末长江作用减弱较大。江湖作用一定程度上影响着湖区旱涝灾害的产生,当五河来流较大且长江顶托作用明显时,易发生洪涝;当五河来流较小但又对长江有明显的补水作用时,易发生旱情,三峡水库蓄水使湖区9-10月更易发生干旱。  相似文献   

14.
藏南羊卓雍错流域水化学区域差异及其成因   总被引:6,自引:1,他引:5  
孙瑞  张雪芹  郑度 《地理学报》2013,68(1):36-44
特殊的地理环境造成青藏高原高寒区水化学性质及其动态的特殊性。本文通过对藏南羊卓雍错流域进行水样采集、分析与测定, 探讨了该流域水化学性质的区域差异及其成因。结果表明, 羊卓雍错流域水化学性质区域差异明显主要是自然因素综合作用的结果, 而人类活动对区域水化学性质亦有所贡献。首先, 在特殊的高寒气候条件下, 流域内各湖泊水化学性质差异的根本原因是其水文条件不同。其次, 羊卓雍错西南部湖水样品中硼和锂含量偏高说明该区域湖相沉积中可能存在硼酸盐矿物和含锂菱镁矿。第三, 流域东部和西部河水化学性质差异明显的主因是河流所经地区地质条件不同;羊卓雍错南岸和北岸地下水化学性质差异的关键则是区域水系发育程度不同。此外, 巴纠错、嘎马林河和羊卓雍错南岸水井样品的总氮含量较高, 这反映了人类活动对区域水化学性质的影响。  相似文献   

15.
以参考历史文献、实地调查和访问当地居民的方法,研究了石羊河中下游流域的植被演替。结果表明,该流域2000多年前为湖泊、沼泽和平原景观,后来由于气候和水文演化、人类活动加强和干旱加剧,导致湖泊与河流逐渐消失、绿洲因水系的变迁而向东南移动、早期的绿洲农田逐渐沙漠化,也使植被从水生、沼泽、草甸植物向沙旱生、强旱生、超旱生方向演替,物种大量消失,已演化成现在的沙漠、戈壁与绿洲景观。目前, 该流域红崖山水库以南的一些河道中尚有常年流水,河漫滩和湿地中还有水生、沼泽、草甸和中生植物种类,物种相对丰富;而水库以北的古河床及广大荒漠区植被稀疏,且多为沙旱生和强旱生植物种类,生物多样性低,稳定性差,沙漠化过程加强。要恢复流域植被、遏制土地沙漠化,应当采用调水、引水和节约用水的方法,加强绿洲保护,使地下水位恢复至植物可吸收利用状态。  相似文献   

16.
The blocking or reversing effect of the downstream trunk river on its tributary lakes is an essential aspect of river-lake hydraulics. To measure how and the extent to which a trunk river can influence its tributary lakes, we made a case study in Changjiang River and one of its tributary lakes, Lake East Dongting (Lake ED) during a 35-year study period (1980–2014). Specifically, we investigated Lake ED’s discharge ability into Changjiang River using stage-discharge relationship curves, and hence the changes of the lake discharge ability under different hydrologic conditions of the Changjiang River. The results show that (1) the Changjiang River does exert a huge impact on the water regimes of Lake ED. And this impact varies seasonally. A variation of 3000 m3/s in Changjiang River’s runoff would change the lake water level by about 1.1 m in dry seasons, by 0.4 m in wet seasons, and by 0.6 m during severe summer floods. (2) Changes in the Changjiang River runoff triggered by the Three Gorges Dam since 2003 have led to dramatic water regime variations in Lake ED. Other factors, including reduction of lake inflow and the lake bed erosion, also exacerbated the water regime variations in Lake ED.  相似文献   

17.
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that: except Xiliao River is "median", the rest are all upon "good", the Dongliao River is even "very good". The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that: considering "quantity", except Xiliao River, the rest rivers can all achieve the "quantity" criteria of the en- vironmental flows of river requirements, but if considering the aspect of "quality", only Dongliao River can reach the "quality" standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands.  相似文献   

18.
《Polar Science》2014,8(3):232-241
This study analyzes long-term (40–60 years) discharge and water temperature records collected near the basin outlets of the Yukon and Mackenzie Rivers. It defines seasonal cycles of discharge, water temperature (WT), and heat flux (HF) for the basins, and compares their main features to understand their similarity and difference. Both rivers have similar hydrographs, i.e. low flows in winter and high discharge in summer, with the peak flood in June due to snowmelt runoff. Mackenzie River has many large lakes and they sustain the higher base flows over the fall/winter season. Mackenzie basin is large with high precipitation, thus producing 50% more discharge than the Yukon River to the Arctic Ocean. The WT regimes are also similar between the two rivers. Yukon River WT is about 2–3 °C warmer than the Mackenzie over the open water months. Both rivers have the highest WT in the mid summer and they transport large amount of heat to the polar ocean system. Yukon River monthly HF is lower by 10–60% than the Mackenzie mainly due to smaller discharge. Mackenzie River heat transport peaks in July, while the Yukon HF reaches the maximum in June and July. These results provide critical knowledge of river thermal condition and energy transport to the northern seas. They are useful for large-scale climate and ocean model development and validation, and climate/hydrology change research in the northern regions.  相似文献   

19.
基于相互作用视角分析了河流与城镇体系结构形成的关联特征及空间表现。河流作为重要自然要素,与城镇体系结构的形成演变存在紧密的关联性,并在空间上表现出不同的特征,研究结果表明:1从数量结构来看,城镇依河流呈非均衡集中分布格局;2规模结构方面,城镇对河流依赖随规模递增而增强,且大城市分布与河流等级、区位密切相关;3职能结构方面,沿河城镇职能具有河流属性特征,且区域中心城市或综合性城市多沿河分布;4空间结构方面,河流引导沿岸城镇空间布局分异,改变中心地空间布局理论结构,且引导沿岸城镇空间体系呈现出点—轴、双核等结构模式。  相似文献   

20.
王西琴  刘昌明  张远 《地理学报》2006,61(11):1132-1140
通过考虑水的自然循环与水在人类活动影响下的循环 (二元水循环),后者包括水资源开发利用率、耗水率、污水排放浓度影响,探讨了二元水循环下河流生态需水“质”与“量”的综合评价,以区别以往仅从自然水循环 (一元) 出发评价河流生态需水的缺陷。建立了二元水循环下的河流生态需水的水量与水质计算方法,并确定了河流生态需水的“质”与“量”的评价标准,实现了河流生态需水水量与水质的综合评价。以辽河流域为例进行实证分析,计算了一元水循环下西辽河、东辽河、辽河干流、浑太河、东北沿黄渤海诸河等水资源分区的河流生态需水,分别占径流的39.3%、63.0%、43.9%、43.3%、43.5%,采用Tennant推荐流量及等级进行评价,结果是:除西辽河属于“中”等级外,东辽河、浑太河、辽河干流、东北沿黄诸河等均在“好”等级以上,东辽河达到“极好”等级。与之对应的二元水循环下的河流生态需水比例分别是57.5%、74.1%、60.8%、60.3%、60.4%,综合评价结果显示:从水量角度评价,西辽河不能达到生态需水“量”的标准,其余能够达标,从水质角度评价,西辽河、浑太河、辽河干流、东北沿黄诸河等均不能够达到“质”的标准,东辽河可以达标。从“量”与“质”相结合的角度评价,仅有东辽河可以达标。因此,水质状况是决定辽河流域河流生态需水是否满足生态系统需求的主要问题。  相似文献   

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