无定河流域极端泥沙变化特征及其影响因素  

Variation Characteristics of Extreme Sediment and Its Influencing Factors in the Wuding River Basin

作　　者：李梦楠 于坤霞[1,2] 张翔 杨志 李鹏[1,2] 李占斌[1,2] LI Mengnan;YU Kunxia;ZHANG Xiang;YANG Zhi;LI Peng;LI Zhanbin(State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi’an University of Technology,Xi’an 710048;Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions,Xi’an University of Technology,Xi’an 710048;Intelligent Environmental Protection Integrated Command Center,Xi’an Bureau of Ecology and Environment,Xi’an 710018;Ningxia Soil and Water Conservation Monitoring Station,Yinchuan 750002)

机构地区：[1]西安理工大学省部共建西北旱区生态水利国家重点实验室,西安710048 [2]西安理工大学旱区生态水文与灾害防治国家林业局重点实验室,西安710048 [3]西安市智慧环保综合指挥中心,西安710018 [4]宁夏回族自治区水土保持监测总站,银川750002

出　　处：《水土保持学报》2023年第1期114-122,共9页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(52079104);宁夏区水利科技项目(SBZZ-J-2021-12);陕西省博士后科研项目(2018BSHQYXMZZ06)。

摘　　要：近几十年来,全球气候变化异常,极端水文事件频繁发生,认识极端泥沙的动态变化并探究其可能影响因素对于预防泥沙灾害具有重要的现实意义。以黄河中游无定河流域为研究对象,从量级、时间、强度和频次4个方面,构建最大1日含沙量(Sx1d)、最大5日含沙量(Sx5d)、年最大1日含沙发生时间(DSx1d)、年最大5日含沙发生时间(DSx5d)、年均含沙量(Sint)、强含沙量(S95p)、极强含沙量(S99p)、高含沙水流日数(S200)共8个极端泥沙指标,采用Mann-Kendall趋势检验、圆分布统计法分析极端泥沙指标的变化趋势及时间分布特征,基于Pettitt检验判定指标变异时间,并应用RVA法定量评价各指标的变化程度,最后探讨降雨侵蚀力和生态建设措施对极端泥沙变化的影响,以及造成极端泥沙变化的主要因素。结果表明:(1)1958—2018年,无定河流域极端泥沙指标均呈显著减小趋势(p<0.05);(2)Sx1d的发生高峰期为6月30日至8月18日,Sx5d的发生高峰期为7月11日至8月17日,比Sx1d的发生时间更为集中;(3)S200发生中度改变,Sx1d、Sx5d、Sint、S95p和S99p发生高度改变,且S95p和S99p的改变度最大,改变度达-100%,极端泥沙指标整体改变度为83.72%,属于高度改变;(4)1963—1966年,降雨侵蚀力的降低在一定程度上导致无定河流域极端泥沙的减少;1982—2018年,NDVI和年累积坝控面积(A d)与极端泥沙指标均呈显著负相关(p<0.05),且通径分析表明,A d比NDVI对极端泥沙指标的直接作用更大,是影响极端泥沙变化的主要因素。研究成果有助于增强对无定河流域极端泥沙变化的认识,为制定泥沙灾害防范策略提供一定的理论依据。In recent decades,global climate has changed abnormally and extreme hydrological events have occurred frequently.It is of great significance to understand the dynamic changes of extreme sediment and explore its possible influencing factors for preventing sediment disasters.In this study,the Wuding river basin in the middle reaches of the Yellow River was taken as the research object.From the four aspects of magnitude,time,intensity and frequency,eight extreme sediment indexes were established,including annual maximum 1-day sediment concentration(Sx1d),annual maximum 5-days sediment concentration(Sx5d),occurrence date of annual maximum 1-day sediment concentration(DSx1d),occurrence date of annual maximum 5-days sediment concentration(DSx5d),average annual sediment concentration(Sint),high sediment concentration(S95p),extremely high sediment concentration(S99p),and days of hyperconcentrated flows(S200).Mann-Kendall trend test and circular statistical approach were used to analyze the variation trend and time distribution characteristics of extreme sediment indexes.The change-point of indexes was determined based on Pettitt test,and the range of variability approach was used to quantitatively evaluate variation of each index.Finally,the influence of rainfall erosivity and ecological construction measures on extreme sediment changes are discussed.The results showed that:(1)From 1958 to 2018,all extreme sediment indexes of Wuding river basin showed a significant decreasing trend(p<0.05).(2)The rush period of Sx1d was from June 30 to August 18,and the rush period of Sx5d was from July 11 to August 17,which was more concentrated than that of Sx1d.(3)S200 reached moderate alteration,Sx1d,Sx5d,Sint,S95p and S99p reached high alteration,and S95p and S99p had the largest alteration,with alteration of-100%.The overall change of extreme sediment indexes was 83.72%,which belonged to high alteration.(4)During 1963—1966 period,the decrease of rainfall erosivity led to a reduction of extreme sediment in the Wuding river basin t

关 键 词：无定河 极端泥沙 影响因素 圆分布统计法 

分 类 号：TV145[水利工程—水力学及河流动力学]