藏西南典型危险性冰湖监测与泥石流溃决模拟  

Typical Monitoring of Dangerous Glacial Lakes in Southwestern Tibet,China and Simulation of GLOF Debris Flow

作　　者：王翔[1] 陈果 戴晓爱[1] 陈永俊[3] 张诗琪 WANG Xiang;CHEN Guo;DAI Xiaoai;CHEN Yongjun;ZHANG Shiqi(College of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China;College of Ecology and Environment,Chengdu University of Technology,Chengdu 610059,China;School of Resources and Safety Engineering,Central South University,Changsha 410083,China)

机构地区：[1]成都理工大学地球科学学院,成都610059 [2]成都理工大学生态环境学院,成都610059 [3]中南大学资源与安全工程学院,长沙410083

出　　处：《山地学报》2021年第5期687-700,共14页Mountain Research

基　　金：成都理工大学“珠峰科学研究计划”(80000-2020ZF11410);青藏高原及其东缘人文地理研究中心开放基金(RWDL2021-ZD003)。

摘　　要：藏西南地区位于喜马拉雅山脉中段,是我国冰湖溃决泥石流频发的重灾区之一。冰湖溃决泥石流数值模拟有助于认识灾害机理和评估灾害风险。冰湖溃决研究大多关注溃决洪水,针对青藏高原冰湖溃决泥石流的仿真模拟较少。本文基于1976—2018年Landsat系列遥感影像、野外调查和FLO-2D水文动力学模型等数据与方法,对藏西南地区典型冰湖强宗克措和吉莱普措开展动态变化分析、地貌调查和溃决泥石流模拟。结果表明:(1)气候变暖使得冰川不断退缩,致使典型冰湖规模持续扩张,强宗克措与吉莱普措的规模在近40 a分别增长了0.61 km^(2)和0.26 km^(2);(2)触发冰湖溃决的地貌环境充分发育,冰湖发生溃决的潜在可能性增大,其中强宗克措尤为明显。因此,需进一步加强对强宗克措等典型冰湖的监测、预防和溃决灾害的治理;(3)FLO-2D模型可有效模拟复杂的冰湖溃决泥石流,有助于评估冰湖溃决灾害对下游的影响,模拟结果可作为制定下游地区灾害防治措施的依据。Southwest Tibet is one of the hardest hit areas in the middle of the Himalayas of China haunted by debris flows relevant to glacial lake outburst flood(GLOF).Most of the studies on GLOF were merely concerned with flood themselves,but few attentions were paid to the simulations on debris flow mobilization caused by GLOF in the Qinghai-Tibet Plateau,China.It is quite believed that numerical simulation is an appropriate approach to interpretation of the mechanism of GLOF-related debris flow and assess their risks.In this study,it addressed typical glacial lakes,Qiangzongkeco and Gelhaipuco in southwest Tibet as case study.Investigation on dynamic change of glacial lake,simulation of GLOF-related debris flow was organized by field survey,analysis of Landsat series remote sensing images from 1976 to 2018 and FLO-2D hydrodynamic modelling.The results are those:(1)Climate warming caused glaciers to retreat continuously,resulting in the continuous expansion of typical glacial lake.The scales of Qiangzongkeco and Gelhaipuco in past 40 years had increased by 0.61 km^(2) and 0.26 km^(2),respectively;(2)Southwest Tibet is a fully developed periglacial goe-environment favorable to glacial lake outburst.The potential to GLOF had been increasing,especially at Qiangzongkeco and Gelhaipuco.The retreat area of the parent glaciers at Qiangzongkeco and Gelhaipuco reached about 1 km 2,and the average annual retreat rate reached 17%at Gelhaipuco and 13%at Qiangzongkeco,respectively.Therefore,it is necessary to further strengthen the monitoring,prevention,and management of outburst disasters in typical glacial lakes such as Qiangzongkeco;(3)FLO-2D model could properly simulate the complicated GLOF-related debris flow,to evaluate the impacts of GLOF-related disasters on the downstream.According to our simulation,GLOF-relate debris flow at Gelhaipuco had the maximum flow velocity in the channel was about 14.1 m/s,with an average flow velocity 2.8 m/s and inundation depth 11.6 m.The whole inundation area was 4.9 km 2.Our research achievem

关 键 词：藏西南 冰湖溃决 遥感监测 数值模拟 

分 类 号：P954[天文地球—自然地理学]