Development And Application Of Ice And Snow Disaster Geographic Information System In Palong Basin

The Palong River is the largest tributary of the Yarlungzangbo River,located in the Linzhi region of eastern Tibet.It also is the main traffic route for the Sichuan-Tibet and Yunnan-Tibet reservoirs.Because of the deep valleys in the Palongzangbo River and the large height difference in landforms,which provides a good potential energy condition for gravity disasters such as avalanches.Furthermore,due to the high elevation of the entire basin,there are many glaciers and glacier lakes on the snow-covered areas on both sides of the mountain.In this paper,GIS technology is used to establish a geospatial information system for the ice and snow disasters in the Palongzangbu basin.The following researches have been conducted:(1)Using Geodatabase data model,SQL Server 2008 storage mechanism,ArcSDE technology to store and manage data;using ArcEngine and program development language(C#)to develop ice and snow disaster of Parlong River information system system.(2)Establish an avalanche evaluation factors index system based on the principle of avalanche,and use AHP combined with a multi-level fuzzy comprehensive evaluation method to carry out risk partitioning of the avalanche disaster in the Parlongzangbu Basin.(3)Using the empirical formula of avalanche forming region to calculate the potential avalanche forming region in the Palongzangbu Basin,and selecting the potential avalanche forming region above the glacier lakes;using the modified avalanche formula to calculate the potential avalanche potential to determine the impact of avalanches on the risk of glacier lakes.(4)Take the Midui glacier lake as an example,use the HEC-RAS software to calculate the height of the water line at each section after the glacier lakes broke and realize the 3D display.(5)Taking the Yigong River out burst flood as an example,this paper discusses the basic idea of road construction to deal with extreme flood events.This paper provides the basis for disaster prevention and control of the Plongzangbu Basin,and also explores in advance the construction of the follow-up of the Sichuan Tibet railway and the Yunnan Tibet Railway in the future.