基于W_(it)指数的冰川型泥石流的年轮定灾方法  

New Reconstruction of Glacier Debris Flows Based on Tree Ring Response

作　　者：皋子琪 吕立群 周冠宇 黄锋 马超[1] 陶正想 梁锦杭 王兆印[2] Gao Ziqi;Lv Liqun;Zhou Guanyu;Huang Feng;Ma Chao;Tao Zhengxiang;Liang Jinhang;Wang Zhaoyin(College of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Hydrology and Sediment Science,Tsinghua University,Beijing 100084,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《地球科学》2025年第2期752-762,共11页Earth Science

基　　金：第二次青藏高原综合科学考察(Nos.2019QZKK0903,2019QZKK0902).

摘　　要：冰川型泥石流在瓤打曲流域频发,对当地安全造成了严重威胁,重建泥石流的暴发历史、流动范围和成因,可以为工程建设提供防灾减灾参数.基于树木年轮的愈伤组织和生长抑制响应,给出了年轮生长抑制的评判阈值和年轮定灾的W_(it)指数的新计算方法,并重建了1890—2021年的泥石流的暴发时间和流动范围;用泥石流实际暴发时间验证了年轮生长抑制的评判阈值和W_(it)新计算方法的合理性.结果表明:(1)冰川活跃区年轮生长抑制的阈值修订为25%;(2)W_(it)指数计算需要排除生长释放因子,利用年轮的创伤组织和生长抑制会增大泥石流灾害事件的定年准确率.Glacial debris flows occur frequently in the Rangdaqu River Basin,posing a serious threat to local safety.Reconstructing the eruption history,flow range,and causes of debris flows can provide disaster prevention and mitigation parameters for engineering construction.Based on the cambial injury tissue and growth inhibition response of trees,this study provides a new calculation method for the evaluation threshold of growth inhibition in tree rings and the W_(it)index of debrisflow identification in tree rings,and reconstructs the outbreak time and flow range of debris flows from 1890 to 2021.The results show that:(1)the threshold for growth inhibition in the active zone of glaciers has been revised to 25%;(2)the calculation of the W_(it)index needs to exclude growth release factors,and the use of traumatic tissue and growth inhibition in tree rings can improve the accuracy of dating debris flow events.

关 键 词：泥石流 冰川 愈伤组织 生长抑制 灾害重建 工程地质 

分 类 号：P642.23[天文地球—工程地质学]