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复杂环境下华南东江中上游流域筑坝导致的水文变异 总被引：5，自引：2，他引：3
采用可视化分析软件包XmdvTool来评价复杂环境下东江中上游流域(1952-2002)水文变异以克服常规RVA方法的限制,在分离了气候变化对水文变异影响后,结合RVA方法系统地研究了华南东江中上游流域由于筑坝等人类活动引起的河流水文变异时空演化规律.结果表明:(1)1952-2002间由筑坝导致的最显著的东江中上游流域水文变异是最小3d流量,低流量持续时间、1月平均流量和7月平均流量等3个IHA因子;(2)在河源和岭下两站水文变异9个IHA因子相关图中,1月和2月平均流量,1月平均流量和最小90d流量相关图中各存在一个较为明显的线性回归趋势,表明上述因子存在较明显的相关关系;(3)东江中上游综合水文变异强度由大至小分别为:河源、龙川和岭下.运用高维水文数据可视化分析技术结合RVA方法可有效用于天然河流水文变异时空变化研究,研究结果对于东江河流生态环境管理、生态恢复和水资源一体化管理具有重要意义,可为流域水文变异的理论与方法研究提供借鉴. 相似文献
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Climate change and human activity can cause remarkable hydrological variation.Traits of hydrological series such as runoff before and after the change points could be sig-nificantly different,so the calculation of instream ecological water requirements (EWRs) is confronted with more challenges.Taking the Xitiaoxi River (XTXR) in the upper reach of the Taihu Lake Basin as an example,this paper investigates the calculation of EWRs using the range of variability approach (RVA) under changing environment.The change point diagnosis of the natural and observed runoff series are conducted for XTXR.Then,differences in the hydrological alternation indicators and instream EWRs processes obtained from various daily runoff series are compared.It was found that the natural and observed annual runoff series in XTXR from 1957 to 2018 both show significant variations,and the change points are in 2007 and 1999 respectively.If runoff data before the change points or all runoff data are used,the instream EWRs obtained from natural runoff are significantly lower than those obtained from the observed runoff.At the monthly time step,EWRs differences within a year mainly oc-curred from May to August.Also,calculation results of the instream EWRs are strongly re-lated to the selected period of runoff series.The EWRs obtained using runoff series after the change points have rather acute fluctuation within a year.Therefore,when the RVA method is used under changing environment,the instream EWRs should be prudently determined by comparing different calculation results on the basis of river runoff restoration and variability analysis.To a certain extent,this paper enriches our understanding about the hydrological method for EWRs estimation,and proposes new ideas for future research on EWRs. 相似文献
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变动范围法(RVA)是国内外评价河流水文特征变化的重要方法,但其存在忽略水文年变化特征及中低度改变指标的缺陷。针对此问题,采用CRITIC法结合欧氏距离对传统RVA进行改进,并将改进方法用于黄河源区(唐乃亥水文站),分析黄河源区径流量的水文指标变化趋势和整体水文变异程度。研究结果表明:唐乃亥水文站在1990年时水文情势发生突变,突变后流量呈减少趋势;受干扰后的唐乃亥水文站2/3月份平均流量、年最小7/30/90d流量、年最大90d流量、高流量平均延时、流量平均减少率/增加率共9个指标为中度改变,其余指标为低度改变;黄河源区水文特征年改变度为41.36%,水文指标整体改变度为27.33%,水文情势整体改变度为57.39%,属于中度改变。 相似文献
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A spatial assessment of hydrologic alteration caused by dam construction in the middle and lower Yellow River,China 总被引：5，自引：0，他引：5
The ‘range of variability approach’ (RVA) and mapping technique are used to investigate the spatial variability of hydrologic alterations (HA) due to dam construction along the middle and lower Yellow River, China, over the past five decades. The impacts of climate variability on hydrological process have been removed during wet and dry periods and the focus is on the impacts of human activities, such as dam construction, on hydrological processes. Results indicate the following: (1) The impacts of the Sanmenxia reservoir on the hydrologic alteration are relatively slight with a mean HA value of 0·48, ranking in the last place among the four large reservoirs. (2) Xiaolangdi reservoir has significantly changed the natural flow regime downstream with mean HA value of 0·56, ranking it in first place among the large reservoirs. (3) The results of ranked median degrees of 33 hydrologic alteration indicators for 10 stations in the Yellow River show that the hydrologic alteration of Huayuankou ranks the highest among 10 stream gauges. (4) Impacts of reservoirs on hydrological processes downstream of the dams are closely associated with the regulating activities of the reservoirs. At the same time, alterations of streamflow regimes resulting from climatic changes (e.g. precipitation variability) make the situation more complicated and more hydrological observations will be necessary for further analysis. The results of the current study will be greatly beneficial to the regional water resources management and restoration of eco‐environmental systems in the middle and lower Yellow River characterized by intensified dam construction under a changing environment. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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湖泊生态水位是维持湖泊生态系统结构和功能完整性、维持生物多样性的最低水位,研究湖泊生态水位过程对湖区动、植物栖息地保护和湖泊水资源管理具有重要意义.利用高邮湖1953-2013年日水位资料进行生态水位计算分析,采用M-K法和滑动T法对1953-2013年年均水位进行突变检验,分析高邮湖1953-1992年来水文变化规律,结合年保证率法和年内展布法得到高邮湖逐月最低生态水位过程,并计算出高、低水位发生时间及历时,在此基础上对其1993-2013年生态水位保障程度进行研究.主要结论有:(1)高邮湖年均水位过程突变发生在1997年;(2)高邮湖高水位时期(7-10月)的最低生态水位为5.8 m,水位高于5.9 m的天数要达到111 d左右;低水位时期(12-次年3月)的最低生态水位为5.1 m,水位低于5.3 m的天数要达到96 d左右;其余月份最低生态水位为5.2 m;(3)高邮湖生态水位年内保障程度最低发生在7月,为60.83%,年际保障程度1994年和2001年最低,分别为49.59%和50.41%,低水位天数得不到保障. 相似文献
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