The Middle Reaches Of The Yarlung Zangbo River Dry Tributary Hydrological Features And Glacial Lake Outburst Flood Analysis

The hydrological situation of Qinghai-Tibet highland is very complicated. Because the natuel condition of study is severe, human activity is few there, and the region is low-level developed, the metrohydrological study of Qinghai-Tibet highland is few. The purpose of this paper is to get some deeper study result and new knowledge in metrohydrological character of main stream and important tributaries of the middle reach of the Yalu-znagbu River, through some field investigation and study. Also to get some new conclusion of glacial lakes burst floods, in possibility study of glacial lake burst, and in qualitified study of the safety of the glacial lakes.The first character of this paper introduce the background of this paper, set the goal, content and methodlogy of the study work in this paper. The second chapter of this paper focuses on the meterological character, runoff composition character, why not correspondency of ratio of rainfall and runoff in same period to annual value for Nianchu River, Lasha River, Niyang River and the middle reach of Yalu-zangbu River. The regime in runoff varying between years, and the regime of distribution of runoff depth of some tributaries of these rivers are studied too. The regime of the floods and flood parameters of these rivers are also studied in this paper. The third chapter of this paper focuses on the character of glacial lake of the highland. By studying the investigation and observation data of bursted glacial lakes, analyze and seek a qualifying way of description of the degree of dangerous of the glacial lakes, analysing the meterological condition that made glacial lake to be more dangerous. The periodic character is studied too. The further main result is devolopeing a way to calculate the glacial burst lake.