Analysis Of The Types And Characteristics Of Mountain Disaster Chains In The Qinghai-Tibet Platea

The Qinghai-Tibet Plateau,as a key region with frequent occurrences of mountain hazards in China,is characterized by well-developed fault structures,intense neotectonic activities,complex and diverse lithology,and strong weathering and erosion effects.Against the backdrop of global warming,various extreme climates have emerged successively in the region,leading to the widespread occurrence of earthquakes,collapses,landslides,debris flows,glacial lake outburst floods,and floods,among other hazards.Moreover,these hazards often occur in the form of a chain reaction,amplifying and prolonging the effects of the original hazards.As a result,they have caused unimaginable huge human casualties and economic losses to China and neighboring regions.In this study,the Qinghai-Tibet Plateau was selected as the research area to comprehensively understand the types and characteristics of mountain hazard chains in the region.A large amount of literature data was collected,and the research achievements of previous scholars were summarized and summarized.Fifteen representative major mountain hazard chains that have occurred in the Qinghai-Tibet Plateau since the 20 th century were statistically analyzed through field investigations,literature analysis,and remote sensing interpretation,among other methods.The occurrence process and main controlling factors of typical mountain hazard chains in the Qinghai-Tibet Plateau were analyzed from different angles,and the classification method of mountain hazard chain types was thoroughly discussed.Finally,the types and characteristics of mountain hazard chains in the Qinghai-Tibet Plateau were summarized and concluded.The research achievements of this paper are as follows:(1)Established a database of mountain hazard chains in the QinghaiTibet Plateau,including the time,geographic location,climatic conditions,main triggering factors,disaster processes,disaster areas,and general overview of the hazard chains.(2)Revealed the spatial-temporal distribution characteristics of mountain hazard chains in the Qinghai-Tibet Plateau.In terms of spatial distribution,typical historical major mountain hazard chains in the Qinghai-Tibet Plateau are distributed along rivers and valleys,controlled by topography,geomorphology,and geological structures,showing a zonal distribution pattern.Overall,they are mainly distributed in the eastern and southern margins of the Qinghai-Tibet Plateau,such as the eastern and southern edges.In terms of temporal distribution,the occurrence of hazard chains is mostly concentrated in July and August,showing seasonal,periodic,and long-term cyclic characteristics.(3)It was found that mountain hazard chains exhibit a superposition and amplification effect of multiple hazard types during their evolution process.In addition,due to the large elevation differences in the QinghaiTibet Plateau,mountain hazard chains can affect downstream areas hundreds or even thousands of kilometers away,showing the characteristic of transboundary hazards.(4)Following the principle of selecting typical hazard chains,considering that mountain hazard chains in the Qinghai-Tibet Plateau are mostly distributed in the Yarlung Zangbo River Basin,the Yigong hazard chain,Guxianggou hazard chain,and Tianmo gou hazard chain in the middle and lower reaches of the Yarlung Zangbo River Basin were selected for comparative studies.Through analyzing the general characteristics and developmental features of these three hazard chain cases,the types of mountain hazard chains in the Qinghai-Tibet Plateau were preliminarily classified based on their triggering factors,including rainstorm-induced mountain hazard chains,multi-process-induced mountain hazard chains,and earthquake-induced mountain hazard chains.Subsequently,these three types of mountain hazard chains were further subdivided based on their different chain-generating modes and formation processes,and matched with other cases of hazard chains.(5)A preliminary summary of the main controlling factors of mountain hazard chains in the Qinghai-Tibet Plateau reveals that the occurrence of mountain hazard chains in the Qinghai-Tibet Plateau is the result of multiple factors acting in conjunction,primarily driven by the continuous uplift of the Qinghai-Tibet Plateau and climate warming.However,the most significant controlling factors are earthquakes and extreme climatic events.