Muddy Mekong (6)
|Part of the enormous Mekong Delta region. This shows just how much sediment is being carried down from the Himalayan Mountains all the way down to the sea. This river flows though many countries and is one of the longest in the world. Workshop has a map of the Mekong.|
The river's source, and therefore its exact length, is uncertain, due to the existence of several tributaries in an inaccessible environment. Chinese researchers believe that the source is located in the Jifu Mountains in Zaduo (杂多) County, Yushu (玉樹) Tibet Autonomous Prefecture of northwest China's Qinghai Province, which is some 5,200 meters above sea level. An earlier expedition, led by Michel Peissel, placed the source at the head of the Rupsa-La pass (further west, at an altitude of 4975 meters). Figures for the river's total length therefore vary between 4350 and 4909 km.
Approximately half the river's length is in China, where it is called the Dza Chu in Tibetan in its upper course in Tibet (Chinese: 扎曲; Pinyin: Zá Qū), and more generally the Lancang in Chinese (Simplified Chinese: 澜沧江; Traditional Chinese: 瀾滄江; Pinyin: Láncāng Jiāng), meaning the "turbulent river". Much of this stretch consists of deep gorges, and the river leaves China at an altitude of only 500 meters. The entire river is known as the Meigong in Chinese (Chinese: 湄公河; Pinyin: Méigōng Hé).
The river next forms the border between Myanmar and Laos for 200 km, at the end of which it meets the tributary Ruak River at the Golden Triangle. This point also marks the division between the Upper and Lower Mekong.The river then divides Laos and Thailand, before a stretch passing through Laos alone. It is known as Maè Nam Khong (Mother of all rivers) in both Lao and Thai (แม่น้ำโขง). The Lao stretch is characterised by gorges, rapids and depths of as little as half a meter in the dry season. It widens south of Luang Prabang, where it has been known to flood to 4 km in width and reach 100 meters in depth, although its course remains extremely inconsistent. The endangered Giant Mekong Catfish was traditionally caught in this region once yearly, following auspicious rites officiated by the quondam royal family.
The river again marks the Lao-Thai border in the stretch which passes Vientiane, followed by a short stretch through Laos alone. This includes the Si Phan Don (four thousand islands) region above the Khone Falls near the Cambodian border, where endangered dolphins can be viewed. The falls are all but impassable to river traffic.
In Cambodia, the river is called the Mékôngk or Tonle Thom (great river). The Sambor rapids above Kratie are the last to impede navigation. Just above Phnom Penh is the confluence with the Tonle Sap, the main Cambodian tributary. Below Phnom Penh, it divides into the Bassac and the Mekong proper, which both flow into the Mekong Delta in Vietnam.
In Vietnamese, the river as a whole is known as Mê Kông. The part flowing through Vietnam, known as Sông Cửu Long (river of nine dragons), divides into two major branches, the Tiền Giang (Front River) and Hậu Giang (Back River). These in turn enter the sea through nine estuaries, thus the Vietnamese name.
About 90 million people rely on the river. The area they live in, known as the Greater Mekong Subregion (GMS), is comprised of Yunnan Province in China, Myanmar, Lao PDR, Thailand, Camdodia, and Vietnam.The main livelihood of the people of the GMS is rice production. Approximately 14 million hectares of rice are grown in the GMS.A huge number of rice varieties are grown along the Mekong. Of approximately 100,000 rice accessions in the Rice Gene Bank of the International Rice Research Institute (IRRI), about 40,000 come from the GMS.