国外生态流量政策法规及启示

系统地梳理了国外生态流量相关的政策法规及其主要内容,识别了国外规定对生态流量过程的要求和河道内生态基流的确定标准;通过梳理我国生态流量相关政策、法规、导则和指南,识别了我国目前存在的不足;通过分析国外生态流量政策法规对我国的启示,提出了完善生态流量管理指南、实施生态流量分区分类差异化管理、完善河流生态系统监测体系、加强全过程管理的建议。该研究可为生态流量红线约束标准的制定提供依据,促进河流水能资源开发与生态环境保护统筹协调发展,实现流域可持续发展。     

海城河不同生态保护目标的生态需水研究

近年来海城河生态水量不足,难以保障水生态系统稳定发展.本文对海城河不同生态保护目标的生态需水量进行计算和分析,采用Tennant法计算保障河道生态基流的需水量,基于鱼类健康生存条件计算保障河流生态系统健康发展的生态需水量,采用环境功能设定法计算河流的各环境功能需水量.计算结果表明:保障河道生态基流的生态需水量为0.88...     

渭河上游河道生态基流量研究

为研究渭河上游河道的生态基流量,根据河道的空间结构特征和水文特征,将渭河上游河道划分为3段.根据河道多年实测资料,采用多种方法进行生态基流量可步计算.最后综合考虑多种因素,确定了渭河上游河道各河段的生态基流量.     

基于中位数众数理论的Tennant法改进与应用

在河流生态径流计算中Tennant法应用比较广泛,但其多年平均流量的确定一直是该方法应用的一个难点,以往使用的平均数有时并不能准确反映总体分布的集中趋势,针对这一问题,通过研究实测数据的统计特性,引入中位数及众数理论,对原Tennant法进行改进,有效的去除了极端数据对统计规律的影响,找出了典型流量过程。将其应用在滦河下游生态径流计算中,通过新老方法的比较,认为采用改进后的计算方法得到的结果更加科学合理。该方法具有原理简单、计算过程“透明”等特点,对河流生态环境研究和水资源合理利用具有指导意义。     

缺资料流域的非点源污染模拟研究

针对非点源污染模型在缺资料流域应用较为困难的问题,以赣江袁河流域为例进行研究。通过插补延长、参数移用等技术手段处理分析,构建了基于分布式SWAT模型的袁河流域非点源污染模拟方案。对流域内水量、泥沙及主要污染物氨氮（NH3-N）和总氮（TN）模拟计算结果显示,纳西效率系数和相关系数基本达到0.7以上,模拟精度较为满意,说...     

生态需水量计算Tennant法的改进及应用

为弥补Tennant法不适用流量季节性变化大的河流的不足,采用典型年流量代替多年平均流量,对Tennant法进行改进;同时,给出典型年的选取和分期百分比选取方法.改进后的Tennant法应用到黄河下游花园口、艾山和利津站.应用结果表明,改进后Tennant法求得的流量更好地体现了北方河流流量丰枯的季节性;得到黄河下游3站生态流量标准涵盖了各站各个阶段的流量,此标准可以用来评价各站的生态需水过程水平.为计算黄河下游各站生态需水量提供了较为合理的方法.     

基于SWAT模型的沙澧河流域径流模拟

基于SWAT构建沙澧河流域分布式水文模型,通过LA-OAT法进行参数敏感性分析,借助数字滤波技术分割基流;以1997—2002年实测流量对各径流成分进行参数率定和验证;初步分析了35种气候变化情景对径流的影响.研究结果表明率定期和验证期总径流模拟相对误差、相关系数和Nash系数分别为-4.3%、0.82、0.73和19%、0.94、0.87.多情景分析表明,降水增加和温度降低将有利于径流增加,其中,最有利的情景为降雨增加15%,温度降低2℃,径流将增加25%.研究成果将为该流域未来水资源规划与管理提供参考.     

Tennant法计算标准的修正及其应用

为了使Tennant法更适合计算南水北调西线河道内生态需水量,对其计算标准进行了修正.采用实地调查的方法,发现南水北调西线一期工程调水区气温较低,引水河流中鱼类洄游及水生生物的活动期主要集中在7~8月份,而且每年的12月到翌年3月河道均处于冰冻期,所以将Tennant法的用水期修正为7~8月,并将修正后的Tennant法应用于南水北调西线调水区引水枢纽下游的朱倭、朱巴、绰斯甲和足木足4站河道内生态需水量的计算.结果表明修正后的Tennant法计算的生态需水量约占多年平均的25%,可见Ten-nant法对栖息地描述的是否准确直接影响到计算结果.     

一种优化混合式电站生态流量过程的模式

针对采用传统生态基流量计算方法所确定的流量难以兼顾生态效益和经济效益的难题,本文提出了一种适宜于混合式水电站的生态流量过程的优化模式。以栖息地加权可用面积为决策指标,认为优化前后基流量所对应加权可用面积相同时河道生境不发生较大改变,通过优化天然河道生境不适区的方式来调整引水比使生态经济效益达到联合最优。本文以昌波水电站为例,选取长丝裂腹鱼为保护目标,利用丁坝对减水河道生境不适区进行优化,结合目标水生生物繁殖敏感期对水力生境的需求,重点研究了生境不适区的水文情势变化情况并确定了优化后的全年河道生态流量过程。结果表明,当选取3个生境不适区进行优化时,河道生态基流量为多年平均流量的10%,所对应的A为87 782.02 m2,而传统方法所得的基流量为多年平均流量的20 %,所对应的A为87 726.2 m2。在保证水力生境条件不变的情况下,前者的流量大小比后者降低了10 %。依据优化后所得生态基流量及对河道涨落水率的研究结果推求得到的昌波水电站生态流量过程,在满足目标鱼类生存繁殖所需水量的同时,较好地保留了天然栖息地的径流涨落变化和流量脉冲过程,为营造保护鱼类适宜生境和确定优化混合式电站生态流量过程提供了示范,同时为电站的生态调度管理提供了依据。     

北运河河流生态需水分段法研究

我国北方河流生态退化问题及恢复是北方地区经济可持续发展的关键.通过分析北运河河流水环境质量状况,提出了分段量化研究河流生态需水量的方法.采用鱼类生境法、Tennant法和水质模型法,分河段、分时段、分阶段计算了北运河河流的生态需水量.结果显示,北运河河流的多年平均径流量不能满足河流COD和NH3—N自净需水量;计算的河流生态需水量占多年平均河流径流量的84%以上,并且需要大量削减入河废污水才能满足河流特定的环境功能要求.针对不同河段、不同时段和河流生态环境规划的不同阶段,进行河流生态需水研究可为我国北方河流制定适度、可靠的河流开发利用限度提供理论支持.     

Coupling the hydrological and ecological process to implement the sustainable water resources management in Hanjiang River Basin

Research on the combination of hydrological variation and ecological demands plays an important role in water availability assessment and sustainable management on basin scale. An integrative frame, consisting of hydrological regime modelling, ecological water demands estimation and renewable resources management, is given in this paper in order to support the implementation of the sustainable water resources management. The suggested integrative frame has been used to study the integrated water resources management in southern Hanjiang River Basin which is the water source of South-to-North Water Transportation Project in China. SWAT (soil and water assessment tool) model was used to simulate the monthly averaging streamflow and the amounts of ecological water demands in stream were also estimated in order to evaluate the available water resources for the local users and the transportation project. Then we formed the developing scenarioes by coupling the available water resources, the recovering rate of water resources in natural water cycle, the local water use rate and the amounts of the water transported to North, and used the Scheafer model to analyze their evolving trajectories. Eventually, the sustainable water resources management measures were assembled by the comprehensive evaluation of the scenarioes. The research indicates that the integrative frame provided a new way for the integrated water resources management in river basin.     

Water demand for ecosystem protection in rivers with hyper-concentrated sediment-laden flow

Sediment transport is one of the main concerns in a river system with hyper-concentrated flows. Therefore, the water use for sediment transport must be considered in study on the water demand for river ecosystem. The conventional methods for calculating the Minimum Water Demand for River Ecosystem (MWDRE) are not appropriate for rivers with high sediment concentration. This paper studied the MWDRE in wet season, dry season and the whole year under different water-and-sediment conditions in the Lower Yellow River, which is regarded as a typical river with sediment-laden flows. The characteristics of MWDRE in the river are analyzed. Firstly, the water demand for sediment transport (WDST) is much larger than the demands for other riverine functions, the WDST accounts for the absolute majority of the MWDRE. Secondly, in wet season when the WDST is satisfied, not only most of the annual incoming sediment can be transported downstream, but also the water demands for other river functions can be satisfied automatically, so that the MWDRE in wet season is identical to the WDST. Thirdly, in dry season, when the WDST is satisfied, the water demands for other river functions can also be satisfied, but the low sediment transport efficiency results in significant waste of water resources. According to these characteristics and aiming at decreasing sediment deposition in the riverbed and improving the utilization efficiency of water resources, hydrological engineering works can be used to regulate or control flow and sediment so that the sediment incoming in dry season can be accumulated and be transported downstream intensively and thus efficiently in wet season.     

Water demand for ecosystem protection in rivers with hyper-concentrated sediment-laden flow

1IntroductionTheriversystemisoneofthemostimportantnaturalecosystems,andithasquiteintimaterelationshipwithhumanbeings.Theprimaryriverinefunctions,suchaswatertransfer,sedimenttransportation,floodrelease,self-purification,landscapeforrecreationorasbiologicalhabitats,navigationandsoon,havegivenmuchconveniencetohumanproductiveactivitiesanddailylife.Ontheotherhand,thenaturalriversystemhasbeeninterferedextensivelyinrecentyearsbyhumanactivities,andthustheriverecosystemhasbeendamagedandriverinefunction…     

黄河流域时变增益分布式水文模型(Ⅱ)——模型的校检与应用

针对分布式水文的应用问题,结合黄河流域时变增益分布式水文模型,在黄河流域进行了实例研究.对黄河干流17个主要流量控制站进行了连续径流模拟.模拟总水量同实测总水量的相对误差在5%以内,其中有11个站效率系数(确定性系数)在0.8以上,其余的也在0.7以上.最后,运用模型分析了气候变化与人类活动对黄河流域降雨产流的影响.     

三峡水库运用后长江倒灌鄱阳湖特性研究

三峡水库建成后,长江与鄱阳湖的关系变化一直是社会各界关注的热点问题。江水倒灌是长江与鄱阳湖关系的主要特征,其变化特性和发生条件目前仍存在一定争议。本文利用长江干流九江、八里江和大通站及鄱阳湖星子、都昌、康山、湖口站的实测资料,从江湖水位、流量关系及径流的年际、年内变化等方面,分析了三峡水库2003年建成运行后长江干流与鄱阳湖关系的变化。基于能量平衡的基本原理,研究了江水倒灌鄱阳湖的内在机理,提出江水倒灌条件的理论公式。结果表明：1）鄱阳湖具有洪水湖相、枯水河相的特性。都昌站水位在15 m以上时,湖区由河相向湖相过渡;康山站水位在17 m以上时,湖区呈现湖泊特性。2）江水倒灌主要发生在汛期7-9月,7、8、9月分别占倒灌总天数的41.6 %、24.8 %、28.8 %。三峡水库175 m试验性蓄水后,水库汛期拦蓄洪峰,在一定程度上削弱了倒灌强度。3）长江水位高于鄱阳湖水位,长江出现大的洪水过程且鄱阳湖5河总入流消退或过程平稳是倒灌形成的必要条件,而倒灌流量的大小和持续天数主要取决于长江洪水的持续时间和洪峰量级。提出的研究方法和结论可为深入认识江湖关系及影响机理提供参考,也可为鄱阳湖综合治理提供科学依据。     

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

TheYellowRiverBasincoversalargeportionofChina,consistingofcomplicatedlandformswithnoticeabledifferencesfromoneareatoanother.Undertheimpactsofatmosphericcirculationsandmonsoonsystems,itsdifferentpartsareinfluencedgreatlybydissimilarclimate,leadingtoappreciablespatialvariabilityofthelandsurfaceandmeteorologicalaspects,whichhasresultedinthecomplicationofhydrologicalcycleinthebasin[1].Thedistributedhydrologicalmodel,withthespatialdistributioncharactersofmodelstructuresandparameters,isnowconsidere…     

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

For the purpose of water resources management in the Yellow River Basin with highly spatial difference a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff, yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.