气候变化背景下九龙江流域水电梯级开发的水文响应

发布时间：2018-02-11 12:37

本文关键词： 气候变化水电开发水文变化生态流量管理　出处：《厦门大学》2014年硕士论文　论文类型：学位论文

【摘要】：气候变化和人类活动引起流域水环境和水生态的显著变化。研究气候变化背景下流域水电梯级开发的水文效应具有重要意义,其结果可为流域水资源管理及其可持续发展提供支持。流域水资源的可持续利用需要对流域水电开发进行管理,但目前大多研究集中大型、特大型水库／水电站的研究,而对于更具有代表性的中小型水库／水电站开发的水文效应研究知之甚少。本研究以流域中小型水电梯级开发的水文响应为主线,以水电开发强度大,中小型电站密度高的近海流域——九龙江流域为研究对象,利用M-K分析、小波分析、GCMs气候模式、IHA生态水文指数法及RVA分析方法对九龙江流域在气候变化背景下九龙江流域水电开发前后的水文变化进行研究分析,其主要结论如下：本研究发现九龙江流域近年来受到人类活动特别是水电开发的扰动逐渐增强,其水文效应显著。近40年来九龙江流域Flashiness指数显著下降,基流指数显著上升。由于九龙江流域水电梯级开发,九龙江北溪、西溪的水文情势分别在2000年及1995发生的显著变化。近年来,由于降水、湿度的增加使的九龙江北溪和西溪的水资源总量增加了1.86%和3.06%。近40年来九龙江流域气候变化明显,九龙江流域的年降水量近年来有所增加并呈上升趋势,暴雨事件发生的频率有所提高,这种增加趋势从沿海到内陆逐渐减弱。九龙流域径流量的变化周期性显著,存在一个以4-5年为周期的径流变化周期,其变化受ENSO变化的影响,但影响九龙江流域径流周期性变化的还是以降水的年际变化为主,其径流的年际变化显著。九龙江流域受水电开发影响显著,水文变化特征明显。从总体来看,主要表现为径流的高、低变化。由于水电梯级开发,九龙江流域的七月至一月份的径流量有所上升而二月至五月份的径流有所下降。流域面积较小的九龙江流域西溪的月径流量变化对水电开发响应更为强烈,其月径流量变化更为剧烈。由于水电开发,导致了九龙江流域径流量变得更为均一,主要表现为年最小径流有所上升及年最大径流量有所下降,出现了湖库化现象。水电开发后,九龙江流域的极端径流事件发生的时间有所改变化,表现为极高径流事件发生时间的提前和极小径流事件发生时间的滞后。相比之下,九龙江北溪流域径流量高低脉冲特征变化显著。本研究进一步表明,九龙江流域生态径流管理需注意径流量及速率、频率的管理。
[Abstract]:Climate change and human activities cause significant changes in water environment and aquatic ecology. It is of great significance to study the hydrological effects of hydropower cascade development in watersheds under the background of climate change. The results can provide support for watershed water resources management and its sustainable development. The sustainable use of watershed water resources requires the management of watershed hydropower development, but at present, most of the studies focus on large-scale, super-large reservoirs / hydropower stations. But little is known about the hydrological effects of the development of more representative small and medium sized reservoirs / hydropower stations. The main line of this study is the hydrological response of cascade development of small and medium-sized hydropower stations in the basin, and the research object is the offshore watersheds of high intensity of hydropower development and high density of small and medium-sized hydropower stations, Jiulong River Basin, which is analyzed by M-K. The hydrological changes of Jiulong River Basin before and after hydropower development in Jiulong River Basin under the background of climate change were studied by wavelet analysis, GCMs and RVA. The main conclusions are as follows:. In this study, it is found that the disturbance caused by human activities, especially hydropower development, is gradually increasing in Jiulong River Basin in recent years, and its hydrological effect is obvious. The Flashiness index of Jiulong River Basin has decreased significantly in the past 40 years. The basic flow index increased significantly. The hydrological situation of the North and West Rivers of Jiulong River changed significantly in 2000 and 1995, respectively, due to the hydropower cascade development in the Jiulong River Basin. In recent years, due to precipitation, The increase of humidity increased the total water resources of North and West streams of Jiulong River by 1.86% and 3.06 respectively. In the last 40 years, the climate change in Jiulong River basin is obvious, the annual precipitation in Jiulong River basin has increased in recent years, and the frequency of rainstorm events has been increased. This increasing trend gradually weakens from the coast to the inland. The variation of runoff in Kowloon basin is periodic and remarkable, and there exists a runoff variation cycle with a period of 4-5 years, which is influenced by the change of ENSO. However, the interannual variation of precipitation is the main factor affecting the periodic variation of runoff in Jiulong River Basin, and the interannual variation of runoff is significant. The Jiulong River basin is affected by hydropower development and hydrologic characteristics are obvious. Generally speaking, it mainly shows the high and low variation of runoff. As a result of hydropower cascade development, From July to January, the runoff of Jiulong River Basin increased, and the runoff from February to February decreased. The monthly runoff change of Xixi River in Jiulong River Basin was more strongly responsive to hydropower development. As a result of hydropower development, the runoff of the Jiulong River Basin became more uniform, mainly as the minimum annual runoff increased and the maximum annual runoff decreased. After hydropower development, the time of extreme runoff events in Jiulong River Basin changed, which was manifested by the advance of extremely high runoff events and the lag of minimal runoff events. The study further shows that the management of ecological runoff in Jiulong River Basin should pay attention to the management of runoff rate and frequency.
【学位授予单位】：厦门大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV12;TV212

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