1. Geographic Review

The Mekong River is one of the world's 10th rivers in its river length and has great influences upon nature and societies of the Indo-china Peninsula. The name "MEKONG" originate in Thai language, Mae Nam Khong¹⁾. The source of the Mekong River is in Tibet mountains and is called Dza Chu River (River of Rock). After running through very narrow valley paralling Yangz Jiang and Salween River, the Mekong reach to Yung-Nan Province of China and is called Lancang Jiang (Turbulent River). Via Golden Triangle, the crossing of China, Myanmer and Laos boarder, the Mekong flow into Vientiane Plain. The term, Lower Mekong means downstream segment from the point. There are some notorious rapids for French navigation plan in colonial period before the Mekong get to Cambodia, and the last segment is the Mekong Delta in Viet Nam, which distributes grate influeces to agriculture, especially paddy fields there. According to a sketch on the right, we can see this long river with some segments hereinafter;

1) Originated from the east edge of Tibet belongs to Yung-Nan Province in China and run down to the south
2) Run through the border of Laos PDR and Myanmar
3) Continue running to the south and run through the border of Laos PDR and Thailand
4) Take some right tributaries from Thailand and then run into Cambodia
5) Take some right tributaries including Tonlesap River from Great Lake
6) Start breaking up into plural flows and form vast Mekong Delta in Viet Nam and finally run into the South-China Sea


 

This complicated flow and relationships between each country have created specific history and international relationships of the Mekong River, i.e. many kinds of problems or frictions related to economy and politics among the nations. Therefore this river is often called 'The Danube in Asia' due to its difficulty as an international river. The history of adjustment began from the Mekong River Committee that organized under ECAFE of UN in 1957. After the long war period on Indo-China nations, the committee was reorganized to interim one without Cambodia and then MRC (Mekong River Commission) undertake the task independently against UN. Present members are Viet Nam, Thailand, Cambodia, and Laos followed by China and Myanmar as observers. Now their biggest theme is sustainable developing of the Mekong River. The data²⁾ of each MRC country are below;

 

Here we can see some basic conditions concerning the Mekong River.

 

(2) Length and inclination
Below is a sketch of longitudinal figure of the Mekong River. The altitude data at each points was collected from several sources or was counted backward from its inclination in a span so this is not a rigid information. However this picture might help you understand the Mekong River's topographical figure.

 

The last and lowest point is 0m above sea level, and the first and second lower one is Can Tho City and Long Xuyen City in the Mekong Delta, Viet Nam. These areas on the Delta only have 1.0-3.0m in height and this values also indicate that the most parts of the Mekong Delta is very vulnerable to the influence of tide which has some 4.0m differences between flood tide and ebb tide in maximum.
From its origin, Tibet Mountains, to north Yung-Nan Province has an inclination of 1/290. And at the Luang Prabang Basin, the inclination shows 0.19/1,000 followed by 0.24-0.39/1,000 at the downstream valley³⁾. From this segment to Laos, the slope turns gentler little by little and after running through the Vientiane Plan and Corn Fall located southern Laos, it is no longer make counter line on the map and finally reaches to the Mekong Delta and the South China Sea.