Chuma’er River in Yushu, Qinghai

The Chuma’er River (楚玛尔河), also known as the Qumalai River (曲麻莱河), is the northern source of the Yangtze River, located in the western part of Yushu Tibetan Autonomous Prefecture (玉树藏族自治州), Qinghai Province, China. Originating from the southern foothills of Kekexili Mountain (可可西里山), the river is known for its harsh environment and unique hydrological features. In Tibetan, “Chuma’er” translates to “Red Water River,” and the river also has other names, including Qumalai River and Quma River.

The river flows through one of China’s most remote regions and serves as a vital water source for both wildlife and the local communities. It is also an essential part of the Yangtze River’s ecosystem.

Geographic Location and Basin Features

  • Location: Western Yushu Tibetan Autonomous Prefecture, Qinghai Province, China

  • Source: Southern foothills of Kekexili Mountain, Black Ridge (海拔5432米)

  • Basin Area: 20,800 km²

  • River Length: 515 km

  • Altitude: 5000–5150 meters above sea level

  • Adjacent Features: The river flows near West Jinwulan Lake (西金乌兰湖) and Kekexili Lake (可可西里湖), with surrounding hills and desert-like landscapes.

The Chuma’er River basin is narrow and elongated, situated in the northern region of the Yangtze River source area. It collects water from the southern slopes of the Kunlun Mountains (昆仑山) and merges into the Tongtian River (通天河). The region is characterized by vast, dry river valleys, sand dunes, and scattered salt lakes, with vegetation being sparse due to the dry climate.

River Sources and Flow

The Chuma’er River has two main sources: the northern source and the western source.

Northern Source:

  • Location: Originates from the eastern part of Kekexili Mountain at an altitude of 5301 meters.

  • Flow: It flows southwestward and then turns south, merging with the western source at an elevation of 4780 meters.

Western Source:

  • Location: Begins at the southern foot of Black Ridge (海拔5432米) in Kekexili.

  • Flow: After flowing southward, the river passes through salt lakes before merging with the northern source near Ye Lusuo Lake (叶鲁苏湖).

The river’s main stream continues to flow eastward, passing through several smaller rivers and lakes, including the Duorigaicuo (多尔改错) lake, before merging with the Tongtian River.

Hydrological Characteristics

Water Flow and Seasonal Variations:

  • Average Flow: 8 cubic meters per second, with a peak flow of 42.5 cubic meters per second.

  • Seasonal Flow: The river experiences a significant increase in flow during the wet season (June to October), contributing to approximately 87.5% of the annual runoff.

  • Flow Changes: In certain areas, the river splits into multiple channels during high water periods and narrows during the dry season.

Climate and Environmental Conditions:

  • Precipitation: Average annual precipitation is very low, ranging from 240 to 273 mm, with the highest rainfall occurring in July (near 40 mm).

  • Evaporation: The evaporation rate is significantly higher, with an average of 1410 mm annually.

  • Temperature: The area is one of the coldest in China, with average temperatures reaching -16.9°C in January and 5.5°C in July. The region also experiences extreme temperature fluctuations, with the lowest recorded temperature at -33.2°C.

Landscape and Ecosystem

Sand Dunes and Geomorphology:

The Chuma’er River is surrounded by expansive sand dunes and a landscape shaped by wind erosion. The “crescent-shaped sand dunes” (新月形沙丘) along the riverbanks are some of the tallest in the world, with heights reaching up to 50 meters.

The river’s basin, despite its high altitude, supports several salt lakes, marshes, and seasonal streams. The presence of glaciers and snowmelt from the surrounding mountains contributes to the river’s water supply.

Wildlife:

The Chuma’er River region is a critical habitat for several rare and endangered species, including:

  • Tibetan Antelope (藏羚羊)

  • Wild Yaks (野牦牛)

  • Tibetan Wild Asses (藏野驴)

  • White-lipped Deer (白唇鹿)

  • Wolves

The river is part of the migration path for Tibetan antelope, which travel through the area from June to August each year. The construction of the Chuma’er River Bridge (楚玛尔河大桥) has made it easier for wildlife to migrate across the area.

Water Resource Management and Development

Water Usage:

The Chuma’er River is an essential water source for local wildlife and serves as a lifeline for the surrounding ecosystems. In addition to receiving snowmelt and underground water from the Kunlun Mountain range, the river also sustains the rare animal species in the region.

Hydrological Development:

The river is strategically located near several important hydrological sites, such as the Chuma’er River Hydrological Station (楚玛尔河沿水文站), which monitors the flow and water quality. This station, along with the nearby wildlife corridors and bridges, plays a significant role in supporting both conservation and human activity in the area.