澜沧江(湄公河)正源及其源头的再确定

澜沧江发源于我国青海省,流经云南省南阿河口以下改称湄公河,它是我国乃至世界上重要的国际河流之一。通过对澜沧江源头地区水文、地貌、冰川及河流特征的实地考察,并利用全球定位系统(GPS)、地理信息系统(GIS)和卫星遥感系统(SRS)等技术来确定澜沧江(湄公河)的正源及其源头。依据以河流的长度为主,并参照集水面积、河流水量等要素,确定了澜沧江的正源为扎阿曲,发源于中国青海省玉树藏族自治州杂多县扎青乡海拔5514m的果宗木查山。果宗木查山上的冰川面积为067km²,冰川末端的地理位置是东经94°41’44”、北纬33°42’31”,其海拔高度为5224m

The source of Lancangjiang (Mekong) River

Comprehensive survey and analysis of the headwaters of the Mekong River by use of GPS, GIS and SRS show that the source of the Mekong River is the Zha'aqu River which starts from the terminal of a small glacier on the Guozongmucha Mountain in Zaduo County, Qinghai Province.The altitude of the source is 5 244m, lying between 94°41′44″E and 33°42′31″N. 　　The Mekong River flows through six Asian countries and ranks as the 12th largest river in the world.From the source to its first convergence of bigger tributaries of Zha'aqu River and Zha'naqu River, Ganasongduo ( 94°36′40″E and 33°12′33″N ), the Zha' aqu River has a length of 101.1km, a drainage area of 2634.0km2 and a discharge of 117.4m3 /s which was measured on July 12, 1999.From Zhanahuohuozhudi ( 93°52.926′E and 33°16.534′N ) to Ganasongduo, the Zha'naqu River has a length of 93.0km, a drainange area of 1999.3km2 and a discharge of 32.3m3/s which was measured on July 12, 1999.At the joint ( Ganasongduo ), the current direction of the Zha'naqu River is from west to east and the Zha'aqu River is from north to south. After jointing, the river is called Zaqu River and It's current direction is nearly from north to south.The run of the Zha'aqu River is similar to that of the Zaqu. 　　From Ganasongduo to Changdu in Tibet Autonomous Region, the Zaqu River is 518 km in length.Down from Changdu to the outlet of the river inside China, the river is called Lancangjiang River, which has a drainage area of 167487km2, a length of 2161km and a mean annual discharge of 2180m3/s..