三峡水库不同类型支流河口泥沙淤积成因及趋势
|
摘要
为揭示三峡水库库区不同类型支流河口泥沙淤积的内在机理和变化趋势,本文充分利用水文、泥沙、固定断面和河道地形等原型观测资料,从支流水沙输移规律和河口局部水沙分布特征出发,研究了不同类型支流河口段泥沙淤积规律及主要影响因素的作用机理,探讨其淤积趋势及形成拦门沙的风险。结果表明:三峡水库蓄水后,库区不同类型支流河口普遍淤积,淤积范围及河道形态的变化各有特点;水库蓄水造成水动力条件减弱是河口泥沙淤积的根本原因,淤积幅度和范围主要取决于干支流来沙量和局部河势。在干支流来沙均明显减少的情况下,三峡水库库区支流河口泥沙淤积速度显著下降,形成拦门沙坎的可能性较小。
There are 66 tributaries in the Three Gorges Reservoir(TGR) area, where most of them witnessed pronounced deposition in mouth reach since the impoundment of the TGR. The lasting sedimentation may lead to the formation of outlet bar at mouth section, which generated adverse effects on storage capacity of the TGR and navigation of tributaries. This paper, taking the Modao Creek and Xiangxi River as examples, examines the characteristics and causes of sediment deposition in their mouth sections based on detailed observation data such as flow,sediment, cross section and channel topography. The results show that:(i) after the impoundment of the TGR, a large amount of deposition occurred in its tributary mouth. The maximum deposition thickness of Modao Creek and Xiangxi River mouth sections exceeded10 m from 2004 to 2017. Deposition was basically within the range of 15 km of the mouth section, and the strong depositing zone was focused in the reach of about 5 km away from the river mouth. The sediment deposition in the river mouth mainly occurred in the initial operation period of the TGR, and slowed down particularly since 2010 when the cascade hydropower stations in the middle and lower Jinsha River began to operate;(ii) the weakened hydrodynamic condition in dry season at the tributaries mouth, and the significantly reduced sediment-carrying capacity, are the fundamental causes in responsibility to the intense deposition. Sediment deposited at Modao Creek and Xiangxi River mouth sections mainly came from the mainstream in the form of inverted flow, and partially came from their own basin. The deposition range of sediment and its influence on channel morphology were related to local river regime;(iii) Optimized operation of the TGR since 2010 has not affected the sediment deposition in the tributaries mouth. Decreased sediment concentration in mainstream and tributaries and the maintenance the low water level in flood season do not support the formation of outlet bar of tributaries in the TGR.
There are 66 tributaries in the Three Gorges Reservoir(TGR) area, where most of them witnessed pronounced deposition in mouth reach since the impoundment of the TGR. The lasting sedimentation may lead to the formation of outlet bar at mouth section, which generated adverse effects on storage capacity of the TGR and navigation of tributaries. This paper, taking the Modao Creek and Xiangxi River as examples, examines the characteristics and causes of sediment deposition in their mouth sections based on detailed observation data such as flow,sediment, cross section and channel topography. The results show that:(i) after the impoundment of the TGR, a large amount of deposition occurred in its tributary mouth. The maximum deposition thickness of Modao Creek and Xiangxi River mouth sections exceeded10 m from 2004 to 2017. Deposition was basically within the range of 15 km of the mouth section, and the strong depositing zone was focused in the reach of about 5 km away from the river mouth. The sediment deposition in the river mouth mainly occurred in the initial operation period of the TGR, and slowed down particularly since 2010 when the cascade hydropower stations in the middle and lower Jinsha River began to operate;(ii) the weakened hydrodynamic condition in dry season at the tributaries mouth, and the significantly reduced sediment-carrying capacity, are the fundamental causes in responsibility to the intense deposition. Sediment deposited at Modao Creek and Xiangxi River mouth sections mainly came from the mainstream in the form of inverted flow, and partially came from their own basin. The deposition range of sediment and its influence on channel morphology were related to local river regime;(iii) Optimized operation of the TGR since 2010 has not affected the sediment deposition in the tributaries mouth. Decreased sediment concentration in mainstream and tributaries and the maintenance the low water level in flood season do not support the formation of outlet bar of tributaries in the TGR.
引文
[1]Wang Yuanjian,Xie Wei,Wang Ting,et al.Key factors influencing evolution of sand bars in tributaries of the Xiaolangdi Reservoir.Journal of Sediment Research,2016(6):51-58.[王远见,谢蔚,王婷,等.小浪底水库库区支流拦门沙形成的主因分析.泥沙研究,2016(6):51-58.]
[2]Zhang Junhua,Chen Shukui,Li Shuxia,et al.Sediment transport and morphological changes of the Xiaolangdi Reservoir in early sediment impoundment period.Journal of Hydraulic Engineering,2007,38(9):1085-1089.[张俊华,陈书奎,李书霞等.小浪底水库拦沙初期泥沙输移及河床变形研究.水利学报,2007,38(9):1085-1089.]
[3]Liu Fazhong,Wang Hongzheng,Yang Kai,et al.Characteristics and problems of siltation in the tributary reservoir area of Danjiangkou Reservoir.Yangtze River,2006,37(8):26-28.[柳发忠,王洪正,杨凯,等.丹江口水库支流库区的淤积特点与问题.人民长江,2006,37(8):26-28.]
[4]Hu Chunhong,Wang Yangui.Study on water-sediment optimum allocation in upstream basin and comprehensive measures of sediment control in Guanting Reservoir I:Reservoir sedimentation and general plan of water and sediment control.Journal of Sediment Research,2004(2):11-18.[胡春宏,王延贵.官厅水库流域水沙优化配置与综合治理措施研究I:水库泥沙淤积与流域水沙综合治理方略.泥沙研究,2004(2):11-18.]
[5]Zhao Keyu,Wang Xiaoyan.The deposition feature in branch rivers in reservoir region of XLD Project.Research of Soil and Water Conservation,2005,12(5):168-171.[赵克玉,王小艳.小浪底水库运用初期支流淤积形态分析.水土保持研究,2005,12(5):168-171.]
[6]Yan Tao.Prelininary study on sediment depostion law and prevention of confluence reach in reservoir[D].Wuhan:Wuhan University,2014.[闫涛.库区交汇河段泥沙淤积规律及防治的初步研究[D].武汉:武汉大学,2014.]
[7]Wang Zhaoyin,Li Changzhi,Wang Feixin.Effect of Tongguan's elevation on the fluvial process of the lower Weihe River.Journal of Hydraulic Engineering,2004,35(9):1-8.[王兆印,李昌志,王费新.潼关高程对渭河河床演变的影响.水利学报,2004,35(9):1-8.]
[8]Wang Yangui,Hu Chunhong.Study on Sedimentation and the mouth bar control in Guanting Reservoir.Journal of Sediment Research,2003(6):25-30.[胡春宏,王延贵.官厅水库淤积特点及拦门沙整治措施.泥沙研究,2003(6):25-30.]
[9]Miao Jilun,Mu Dewei,Zhang Xujin,et al.The in fluence of Three Georges Project running on sediment deposition at Wujiang Entrance.Journal of Chongqing Jiaotong University,2003,22(1):105-108,120.[缪吉伦,母德伟,张绪进,等.三峡水库运行对乌江河口段泥沙淤积的影响.重庆交通学院学报,2003,22(1):105-108,120.]
[10]Wu Baosheng,Deng Yue.Effects of controlled pool level in non-flood seasons on the sedimentation in Sanmenxia Reservoir.Journal of Hydroelectric Engineering,2007,26(2):93-98.[吴保生,邓玥.三门峡水库非汛期控制运用水位对库区泥沙冲淤的影响.水力发电学报,2007,26(2):93-98.]
[11]Ma Chao,Lian Jijian.Preliminary research on influence mechanism of human controlled dispatching solutions to hydrodynamics and water quality of tributaries of reservoir.Journal of Tianjin University,2011,44(3):202-209.[马超,练继建.控调度方案对库区支流水动力和水质的影响机制初探.天津大学学报,2011,44(3):202-209.]
[12]Ji Daobin,Liu Defu,Yang Zhengjian,et al.Hydrodynamic characteristics of Xiangxi Bay in Three Gorges Reservoir.Science China,2010,40(1):101-112.[纪道斌,刘德富,杨正健.三峡水库香溪河库湾水动力特性分析.中国科学:物理学力学天文学,2010,40(1):101-112.]
[13]Liu Defu,Yang Zhengjian,Ji Daobin,et al.A review on the mechanism and its controlling methods of the algal blooms in the tributaries of Three Gorges Reservoir.Journal of Hydraulic Engineering,2016,47(3):443-454.[刘德富,杨正健,纪道斌,等.三峡水库支流水华机理及其调控技术研究进展.水利学报,2016,47(3):443-454.]
[14]Peng Chengrong,Chen Lei,Bi Yonghong,et al.Effects of flood regulation on phytoplankton community structure in the Xiangxi River,a tributary of the Three Gorges Reservoir.China Environmental Science,2014,34(7):1863-1871.[彭成荣,陈磊,毕永红,等.三峡水库洪水调度对香溪河藻类群落结构的影响.中国环境科学,2014,34(7):1863-1871.]
[15]Yuan Jing,Xu Quanxi,Tong Hui.Study of sediment deposition in region of Three Gorges Reservoir after its impoundment.Journal of Hydroelectric Engineering,2013,32(2):139-145.[袁晶,许全喜,童辉.三峡水库蓄水运用以来库区泥沙淤积特性研究.水力发电学报,2013,32(2):139-145.]
[16]Li Wenjie,Yang Shengfa,Fu Xuhui,et al.Sedimentation characteristics in the Three Gorges Reservoir during the initial operation stage.Advances in Water Science,2015,26(5):676-685.[李文杰,杨胜发,付旭辉,等.三峡水库运行初期的泥沙淤积特点.水科学进展,2015,26(5):676-685.]
[17]Zhang Yu,Liu Defu,Ji Daobin,et al.Effects of Intrusions from Three Gorges Reservoir on nutrient supply to Xiangxi Bay.Environmental Science,2012,33(8):2621-2627.[张宇,刘德富,纪道斌,等.干流倒灌异重流对香溪河库湾营养盐的补给作用.环境科学,2012,33(8):2621-2627.]
[18]Dong Bingjiang,Chen Xianwei,Xu Quanxi.Investigations and considerations on peak sediment regulation of Three Georges Reservoir.Yangtze River,2014,45(19):1-5.[董炳江,陈显维,许全喜.三峡水库沙峰调度试验研究与思考.人民长江,2014,45(19):1-5.]
[19]Liu Huiying,Lu Xianghui,Zhang Pingcang,et al.Variation of runoff and sediment discharge and its driving factors in Xiangxi River watershed in Three Gorges Reservoir Area.Bulletin of Soil and Water Conservation,2015,35(5):17-21.[刘惠英,鲁向晖,张平仓等.三峡库区香溪河流域水沙关系变化及其驱动因素.水土保持通报,2015,35(5):17-21.]
[20]Sun Rong,Yuan Xingzhong,Liu Hong,et al.Influence of cascaded exploitation of small hydropower on riparian plant communities in Modaoxi River.Advances in Water Science,2011,22(4):561-567.[孙荣,袁兴中,刘红,等.磨刀溪梯级水电开发对河岸植物群落的影响.水科学进展,2011,22(4):561-567.]
[2]Zhang Junhua,Chen Shukui,Li Shuxia,et al.Sediment transport and morphological changes of the Xiaolangdi Reservoir in early sediment impoundment period.Journal of Hydraulic Engineering,2007,38(9):1085-1089.[张俊华,陈书奎,李书霞等.小浪底水库拦沙初期泥沙输移及河床变形研究.水利学报,2007,38(9):1085-1089.]
[3]Liu Fazhong,Wang Hongzheng,Yang Kai,et al.Characteristics and problems of siltation in the tributary reservoir area of Danjiangkou Reservoir.Yangtze River,2006,37(8):26-28.[柳发忠,王洪正,杨凯,等.丹江口水库支流库区的淤积特点与问题.人民长江,2006,37(8):26-28.]
[4]Hu Chunhong,Wang Yangui.Study on water-sediment optimum allocation in upstream basin and comprehensive measures of sediment control in Guanting Reservoir I:Reservoir sedimentation and general plan of water and sediment control.Journal of Sediment Research,2004(2):11-18.[胡春宏,王延贵.官厅水库流域水沙优化配置与综合治理措施研究I:水库泥沙淤积与流域水沙综合治理方略.泥沙研究,2004(2):11-18.]
[5]Zhao Keyu,Wang Xiaoyan.The deposition feature in branch rivers in reservoir region of XLD Project.Research of Soil and Water Conservation,2005,12(5):168-171.[赵克玉,王小艳.小浪底水库运用初期支流淤积形态分析.水土保持研究,2005,12(5):168-171.]
[6]Yan Tao.Prelininary study on sediment depostion law and prevention of confluence reach in reservoir[D].Wuhan:Wuhan University,2014.[闫涛.库区交汇河段泥沙淤积规律及防治的初步研究[D].武汉:武汉大学,2014.]
[7]Wang Zhaoyin,Li Changzhi,Wang Feixin.Effect of Tongguan's elevation on the fluvial process of the lower Weihe River.Journal of Hydraulic Engineering,2004,35(9):1-8.[王兆印,李昌志,王费新.潼关高程对渭河河床演变的影响.水利学报,2004,35(9):1-8.]
[8]Wang Yangui,Hu Chunhong.Study on Sedimentation and the mouth bar control in Guanting Reservoir.Journal of Sediment Research,2003(6):25-30.[胡春宏,王延贵.官厅水库淤积特点及拦门沙整治措施.泥沙研究,2003(6):25-30.]
[9]Miao Jilun,Mu Dewei,Zhang Xujin,et al.The in fluence of Three Georges Project running on sediment deposition at Wujiang Entrance.Journal of Chongqing Jiaotong University,2003,22(1):105-108,120.[缪吉伦,母德伟,张绪进,等.三峡水库运行对乌江河口段泥沙淤积的影响.重庆交通学院学报,2003,22(1):105-108,120.]
[10]Wu Baosheng,Deng Yue.Effects of controlled pool level in non-flood seasons on the sedimentation in Sanmenxia Reservoir.Journal of Hydroelectric Engineering,2007,26(2):93-98.[吴保生,邓玥.三门峡水库非汛期控制运用水位对库区泥沙冲淤的影响.水力发电学报,2007,26(2):93-98.]
[11]Ma Chao,Lian Jijian.Preliminary research on influence mechanism of human controlled dispatching solutions to hydrodynamics and water quality of tributaries of reservoir.Journal of Tianjin University,2011,44(3):202-209.[马超,练继建.控调度方案对库区支流水动力和水质的影响机制初探.天津大学学报,2011,44(3):202-209.]
[12]Ji Daobin,Liu Defu,Yang Zhengjian,et al.Hydrodynamic characteristics of Xiangxi Bay in Three Gorges Reservoir.Science China,2010,40(1):101-112.[纪道斌,刘德富,杨正健.三峡水库香溪河库湾水动力特性分析.中国科学:物理学力学天文学,2010,40(1):101-112.]
[13]Liu Defu,Yang Zhengjian,Ji Daobin,et al.A review on the mechanism and its controlling methods of the algal blooms in the tributaries of Three Gorges Reservoir.Journal of Hydraulic Engineering,2016,47(3):443-454.[刘德富,杨正健,纪道斌,等.三峡水库支流水华机理及其调控技术研究进展.水利学报,2016,47(3):443-454.]
[14]Peng Chengrong,Chen Lei,Bi Yonghong,et al.Effects of flood regulation on phytoplankton community structure in the Xiangxi River,a tributary of the Three Gorges Reservoir.China Environmental Science,2014,34(7):1863-1871.[彭成荣,陈磊,毕永红,等.三峡水库洪水调度对香溪河藻类群落结构的影响.中国环境科学,2014,34(7):1863-1871.]
[15]Yuan Jing,Xu Quanxi,Tong Hui.Study of sediment deposition in region of Three Gorges Reservoir after its impoundment.Journal of Hydroelectric Engineering,2013,32(2):139-145.[袁晶,许全喜,童辉.三峡水库蓄水运用以来库区泥沙淤积特性研究.水力发电学报,2013,32(2):139-145.]
[16]Li Wenjie,Yang Shengfa,Fu Xuhui,et al.Sedimentation characteristics in the Three Gorges Reservoir during the initial operation stage.Advances in Water Science,2015,26(5):676-685.[李文杰,杨胜发,付旭辉,等.三峡水库运行初期的泥沙淤积特点.水科学进展,2015,26(5):676-685.]
[17]Zhang Yu,Liu Defu,Ji Daobin,et al.Effects of Intrusions from Three Gorges Reservoir on nutrient supply to Xiangxi Bay.Environmental Science,2012,33(8):2621-2627.[张宇,刘德富,纪道斌,等.干流倒灌异重流对香溪河库湾营养盐的补给作用.环境科学,2012,33(8):2621-2627.]
[18]Dong Bingjiang,Chen Xianwei,Xu Quanxi.Investigations and considerations on peak sediment regulation of Three Georges Reservoir.Yangtze River,2014,45(19):1-5.[董炳江,陈显维,许全喜.三峡水库沙峰调度试验研究与思考.人民长江,2014,45(19):1-5.]
[19]Liu Huiying,Lu Xianghui,Zhang Pingcang,et al.Variation of runoff and sediment discharge and its driving factors in Xiangxi River watershed in Three Gorges Reservoir Area.Bulletin of Soil and Water Conservation,2015,35(5):17-21.[刘惠英,鲁向晖,张平仓等.三峡库区香溪河流域水沙关系变化及其驱动因素.水土保持通报,2015,35(5):17-21.]
[20]Sun Rong,Yuan Xingzhong,Liu Hong,et al.Influence of cascaded exploitation of small hydropower on riparian plant communities in Modaoxi River.Advances in Water Science,2011,22(4):561-567.[孙荣,袁兴中,刘红,等.磨刀溪梯级水电开发对河岸植物群落的影响.水科学进展,2011,22(4):561-567.]
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |