PROGRESS IN GEOGRAPHY ›› 2015, Vol. 34 ›› Issue (3): 364-372.doi: 10.11820/dlkxjz.2015.03.011

• Hydrology andWater Resource • Previous Articles     Next Articles

Runoff generation in the headwater of Amu Darya, Central Asia

Xiaolei WANG1,2, Lin SUN1, Yiqing ZHANG1,2, Yi LUO1()   

  1. 1. Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    2. University of Chinese Academy of Science, Beijing 100049, China
  • Received:2014-04-01 Revised:2014-12-01 Online:2015-03-25 Published:2015-03-25


Amu Darya is the largest river in Central Asia that provides water resources to downstream water users and flows into the Aral Sea. Runoff of the Amu Darya River is dominated by snowmelt and glacier melt originating from the alpines. Quantification of snowmelt and glacier melt contribution to the runoff is important for understanding the dynamic characteristics of the streamflow. This study investigates the glacier and snow melt processes in the headwaters of Amu Darya by using a glacier-enhanced SWAT model. The simulations were run through 1951 to 2005. The results indicate that the SWAT-RSG model could well estimate the monthly streamflow process of the Amu Darya River Basin, and the efficiency coefficient and absolute value of PBIAS in the calibration period (1961-1975) and validation period (1976-1985) could be higher than 0.6 and lower than 25%, respectively. Snowmelt and glacier melt contributed 67% and 15% of the annual runoff. The Amu Darya River is mainly supplied by melting high-mountain snow and glaciers, which was concentrated in March to July and June to September, respectively. Owning to the combined effect of rainfall, snowmelt, and glacier melt, the runoff is concentrated in April to September, accounting for 83% to the total runoff, and the peak occurred in July. The results of Mann-Kendall trend analysis indicate that precipitation showed a significant decreasing trend and temperature showed a significant increasing trend from 1951 to 2005, and experienced a sudden jump in 1995. Due to the change of temperature and precipitation, snowmelt showed a decreasing trend and the value during 1996 to 2005 (Period Ⅱ) was 20% lower compared to that in 1951 to 1995 (Period Ⅰ). Due to the shrink of glacier area and reduction of precipitation, glacier melt showed a non-significant decreasing trend between 1951 and 2005 and the annual glacier melt in Period Ⅱ was 4% less than that in Period Ⅰ. Despite that the rainfall had slightly increased, the rain runoff was reduced by 35% as a result of the increased evapotranspiration. Consequently, the streamflow was reduced by about 260 million m3 each year from 1951 to 2005. The runoff showed a 21% reduction from Period Ⅰ to Period Ⅱ. The study of runoff generation characteristics in the headwaters of the Amu Darya River can provide references for the water resource management in the Amu Darya River Basin and Central Asia.

Key words: SWAT-RSG model, Amu Darya River, snow runoff, glacier runoff