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1 Quaternary International 244 (2011) 264e271 Contents lists available at ScienceDirect Quaternary International journal homepage: Desiccation of the Tarim River, Xinjiang, China, and mitigation strategy Yaning Chen a, *, Zhaoxia Ye a, Yanjun Shen b a Key Laboratory of Oasis Ecology and Desert Environment, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, South Beijing Road 40-3#, Urumqi, Xinjiang , China b Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Chinese Academy of Sciences, Shijiazhuang , China article info abstract Article history: Available online 13 February 2011 Desiccation of the Tarim River is increasingly severe, as shown by the increases in length affected and time of desiccation. If the tendency is not constrained, the difficulty in water transfer to the lower reach of the Tarim River will be greatly increased, and the ecological security in the river basin and the downstream Green Corridor protection will be severely impacted. This paper analyses the desiccation tendency and hydrological regime of the Tarim River, discusses the causes of this condition, the point of zero flow movement, and the influence on the ecological security in the Tarim River basin that may be caused by the further development of desiccation. The relationship between soil and water resource management and hydrological regime change in the Tarim River basin and river desiccation is analyzed. The main causes of the river desiccation were the increase in irrigated area of the headstream section in the upstream region, the rise in water consumption in the upper and middle reaches, and the construction of reservoirs in the mountain areas. Accordingly, possible countermeasures and ideas for mitigating the desiccation tendency are suggested, so as to provide decision-making references for water resource management and sustainable and healthy social, ecological and economic development in the Tarim River basin. Ó 2011 Elsevier Ltd and INQUA. All rights reserved. 1. Introduction Increasing global climate change and human activity intensity have altered the hydrological regime along with water resource conditions, which have led to the variation of ecological and hydrological processes in river basins (Page et al., 2005). In the arid and semi-arid regions, due to soaring population and unreasonable exploitation, the mainstreams and tributaries of many rivers are deprived of water and the rivers are drying up. As a result, a series of ecological and environmental problems arise in the downstream areas of the desiccated rivers, such as lowering of ground water level, degradation of desert vegetation, destroyed habitats, and decreased biodiversity (Liu and Xia, 2004; Feng et al., 2005). The Tarim River is the longest inland river in China, and is located in the arid region of the northwest. For more than half a century, during large-scale soil and water resource exploitation, the contradiction between production and ecological conservation has become increasingly conspicuous in the Tarim River basin. Due to the highintensity of water resource utilization in the upper reach of the river basin, the downstream 321 km of the river dried up, the * Corresponding author. address: chenyn@ms.xjb.ac.cn (Y. Chen). terminal lakes of the Tarim River (Lop Nor Lake and Taitema Lake) dried up respectively in 1970 and 1972, and the ground water level was greatly lowered. Thus, the desert riparian forest vegetation has degraded severely, the lives of which are supported by the ground water. Wind erosion and desertification have been enhanced, the biodiversity has been damaged heavily, and the Green Passage at the lower reach of the Tarim River, between the Taklimakan Desert and the Kuruk Desert, is on the verge of disappearance. The ecological crisis in the regions along the lower reach of the Tarim River has attracted the attention of the China Central Government, which plans to invest RMB Yuan in the comprehensive treatment of the Tarim River basin. In 2000, the eco-water transfer project for the regions along the lower reach of the Tarim River, the purpose of which is to resume the ecological environment and to save the Green Passage, was implemented by transferring water from Bosten Lake. Owing to the intermittent water transfer in the past several years, the ecological environment in the regions along the lower reach of the Tarim River was preliminarily improved (Chen et al., 2004). However, the tendency of the increase in desiccation of the Tarim River, both in length and time, is still developing, and the desiccation situation is becoming increasingly severe. This makes it much more difficult to transfer water to the lower reach of the Tarim River, and has greatly threatened the ecological security in the river basin /$ e see front matter Ó 2011 Elsevier Ltd and INQUA. All rights reserved. doi: /j.quaint

2 Y. Chen et al. / Quaternary International 244 (2011) 264e Many researchers have analyzed the desiccation of the Yellow River in China along with the subsequent ecological problems, and presented the relationship between the runoff and the desiccation of the Yellow River, and the relevant mechanism of the desiccation. These researchers analyzed the changes in runoff sequence in the Yellow River basin and the influence of the desiccation of the lower reach on ground water formation and exploitation along the river (Liu and Xia, 2004; Cao et al., 2008). Also, many researchers reported the desiccation of the Heihe River in China, and the subsequent ecological problems it caused (Qi and Luo, 2005). The Tarim River basin in Xinjiang, China, occupies the entire southern region in Xinjiang: its area is respectively 1.4 and 8 times the areas of the Yellow River basin and the Heihe River basin. In the plain area in the Tarim River basin the precipitation is little, the arid climate characteristics are prominent, and the extremely weak ecosystem is a unique freshwater ecosystem spatially close to China s largest shifting desert, the Taklimakan Desert. Therefore, the river desiccation and the subsequent ecological and environmental problems are quite conspicuous due to these conditions. This paper considers the main causes of the desiccation of the Tarim River according to the analysis and calculation of the desiccation process and tendency and hydrological regime of the river. Based on the analysis of the existing problems in the management of the river basin, countermeasures and suggestions for mitigating the desiccation tendency are offered, so as to provide references for decision-making for water resource management and sustainable and healthy social, ecological and economic development in the Tarim River basin. Fig. 1. Distribution of the river system in the Tarim River Basin.

3 266 Y. Chen et al. / Quaternary International 244 (2011) 264e Study area and relevant data 2.1. Overview of study area The Tarim River is the largest inland river in China, and is also one of the most famous inland rivers in the world. The Tarim River basin, which has an area of 1.02 million km 2, includes 114 rivers that belong to nine river systems: the Aksu River, the Hotan River, the Yarkand River, the Qarqan River, the Keriya River, the Dina River, the Kaxgar River, the Kaidu-Konqi River, and the Weigan River. The long-term average annual natural runoff of surface water is 39.8 billion m 3, which is mainly replenished through ice and snow melting from high mountain regions and precipitation. In terms of hydrology, the Tarim River basin is a closed catchment area, and is also a unique freshwater ecosystem spatially close to the Taklimakan Desert. In the past fifty years, due to large-scale agriculture reclamation and high-intensity water resource exploitation in the Tarim River basin, the water flowing from the headstream area into the mainstream of the Tarim River decreased constantly. Further, many tributaries have been successively disconnected from the surface water of the mainstream of the Tarim River, and currently there are only three headstreams converging at Xiaojiake and flowing into the Tarim River: the Aksu River, the Hotan River and the Yarkand River (Fig. 1) (Zuo et al., 2004). Out of the three headstreams converging into the mainstream of the Tarim River, the Aksu River is the main source of water supply for the mainstream of the Tarim River, representing 73.2% of the total supply, while the Hotan River and the Yarkand River supply 23.2% and 3.6% respectively (Chen et al., 2003). The Tarim River is a typical inland river in an arid area (Fig. 2). The mainstream of the Tarim River has an overall length of 1321 km. The upper reach extends from Xiaojiake, the convergence of the three headstreams, to the Yenbazar section and its length is 495 km. The middle reach is from the Yenbazar section to the Qiala section and its length is 398 km. The lower reach is from the Qiala section down to the Taitema Lake and its length is 428 km. The area of the river basin is 17,600 km 2. The mainstream of the Tarim River does not generate water flow: the water is all supplied from the three headstreams, thus making the Tarim River a dissipation-only inland river. Therefore, the water source from the upstream/headstream area directly maintain the water flow in the mainstream of the Tarim River, consequently, the 1321 km of mainstream of the Tarim River will become a desiccation riverbed if there is no supply from the three headstreams Data sources The data used for this study were collected from the hydrological stations at the mountain passes of the three headstreams, the Kaqung Hydrological Station for the Yarkand River, Xehera Hydrological Station and Sharikilank Hydrological Station for the Aksu River, and Tongguzlok Hydrological Station and Wruwat Hydrological Station for the Hotan River. The hydrological stations are located above the mountain passes through which the rivers flow. In these particular areas, the runoffs of the rivers are scarcely disturbed by human factors, and thus any runoff change can be considered to be caused by climate change. The data for the water discharge from the three headstreams into the mainstream of the Tarim River were obtained by the Aral Hydrological Station through monitoring. The locations and important parameters of the hydrological stations are shown in Fig. 1 and Table Analysis of the desiccation process and tendency of the Tarim River 3.1. Desiccation development process of the Tarim River For more than 50 years, the Tarim River basin has experienced large-scale soil and water exploitation. The area under cultivation in the Tarim River basin increased from 349,820 ha in 1949 to 607,050 ha in 1995, and the total irrigated area in the river basin exceeded 1.63 million hectares in The water amount for irrigation in the river basin increased from 5 billion m 3 in the 1950s to 20.2 billion m 3 in 2008 (Zheng et al., 2006). In the 1950se1960s, the water in the Tarim River flowed to Taitema Lake and Lop Nor Lake, and the length of the Tarim River was about 1321 km. Lop Nor Lake is the largest lake in Xinjiang. Its area was about 3000 km 2 in the 1930s, reaching 5000 km 2 after an extraordinary flood in 1958 (Zhou, 2009). After the Daxihaizi Reservoir was built in the early 1970s on the Tarim River, the 321 km of river downstream of the reservoir started to desiccate. Because of this, Lop Nor Lake and Taitema Lake dried up in 1972 and 1974, respectively. In the 1990s, the point of zero flow moved upstream to the Qiala section on the lower reach of the Tarim River. The desiccation river length increased from 321 km in the 1970s to 428 km. Entering the 21st century, the length of the desiccation of the river continues to increase along with the point of zero flow. In 2001, desiccation occurred at the Yenbazar section on the middle reach of the mainstream of the Tarim River. Although there was water flowing through the section in 2002 and 2003, in the nonflood season, desiccation occurred during three successive years (2004e2006). During this time, the desiccated river length increased to 826 km. Intermittent desiccation occurred at the Xinquman section on the upper reach of the mainstream of the Tarim River in Desiccation also occurred at the Xinquman section over 14 successive days in 2008, during which time the desiccated river length increased to 1100 km. The point of zero flow moved to above the Xinquman section in 2009, and the desiccated river length increased to 1200 km. In the past 20 years, the point of zero flow in the Tarim River moved from the Qiala section on the lower reach to the Yenbazar section on the middle reach, and then further moved upstream to the Xinquman section on the upper reach. Thus, the point of zero flow moved upstream about 770 km (Fig. 3). Fig. 2. Sketch map of the Tarim River.

4 Y. Chen et al. / Quaternary International 244 (2011) 264e Table 1 Important parameters of hydrological station in the headstreams of the upper reaches of the Tarim River. River Hydrological station Catchment Altitude/m Observation area/km 2 period of time Aksu Kumalak Xehera e2008 River River Tuoshigan Sharikilank e2008 Hotan Kalakash Wruwat e2008 River River Yulongkash Tongguzlok e2008 River Yarkand Kaqung e2008 River Converge spot Aral 1958e2008 Fig. 4. Desiccation time per year in Qiala section since As the point of zero flow moves up and the desiccated river length increases, the desiccation time of the Tarim River rises significantly. Since the beginning of the 1990s, when desiccation occurred at the Qiala section on the lower reach of the Tarim River, desiccation time had increased constantly from 16 days in 1990 to 67 days in 1995 and then to 127 days in The average desiccation time in the 1990s was up to 70 days per year. The number of desiccation days continued to increase after the year 2000, and reached 269 in Currently, the desiccation time at the Qiala section is at 302 days (Fig. 4). The desiccation time has increased constantly at the Yenbazar section on the middle reach of the Tarim River since 2001, when the desiccation first started to occur. The desiccation times were 66 days, 81 days, 25 days, 188 days and 228 days, respectively, in the years 2004 through In 2009, the hydrologic regime in the river grew worse: water has been intermittently flowing through the Yenbazar section only since the beginning of August, when the desiccation time exceeded 230 days Analysis of the desiccation tendency of the Tarim River Water volumes in the headstreams and mainstream The volume of water flowing into the mainstream of the Tarim River from the three headstreams, the Aksu River, the Hotan River and the Yarkand River, was approximately 6.1 billion m 3 in the 1950se1960s, and decreased to 4.4 billion m 3 in the end of 1990s. This is a decrease of 1.7 billion m 3 in 40 years, with an average annual decrease of million m 3. In addition, the water consumption increased continually due to the uncontrolled water utilization along the upper and middle reaches. Therefore, the amount of water reaching the Qiala section on the lower reach decreased increasingly, from 1.27 billion m 3 in the 1950se1960s to billion m 3 by the end of the 1990s. The average annual incoming water flow into the headstream area from the 1950s to the end of the 1990s was about 18.0 billion m 3, and the average annual volume of water flowing into the mainstream of the Tarim River was approximately 4.65 billion m 3. Entering into the 21st century, the Tarim River basin experienced a period with relatively rich water flow, owing to the influence of global climate change. The average annual incoming water amount in the nine years from 2000 to 2008 was about billion m 3, increased by about 15% compared with that in the previous 40 years. However, the amount of water flowing into the mainstream of the Tarim River decreased to less than 4.3 billion m 3. Especially in 2007 and 2008, the incoming water amount into the three headstreams was 3% and 9.9%, respectively, more than the long-term average annual incoming water amount. However, the amount of water flowing into the mainstream of the Tarim River was only 3.15 billion m 3 and 2.8 billion m 3 respectively, 29% and 37% less than the long-term average annual water amount respectively. In 2002, 2005 and 2006, the water amount in the mainstream increased because the incoming water into the three headstreams increased, compared with the previous years. However, the amount of water flowing into the mainstream shows an overall decreasing tendency. The volume flowing into the mainstream decreased before the 1990s, fluctuated at the beginning stage of the 21st century, and decreased again from In addition, the ratio of the amount of water supplied into the mainstream from the three headstreams to the total incoming water into the headstreams decreased from the long-term average annual value of 24e16.4% in 2007 and 13.7% in 2008 (Fig. 5). In 2009, the incoming water into the headstream area was reduced, so the water flowing into the mainstream of the Tarim River was less. The incoming volume from the three headstreams in July 2009 was Fig. 3. Length of desiccation riverway of the Tarim River since 1970 s. Fig. 5. Amount of water flowing into the mainstream and the ratio of the amount of water supplied into the mainstream from the three headstreams to the total incoming water into the headstreams.

5 268 Y. Chen et al. / Quaternary International 244 (2011) 264e271 Fig. 6. Percentage departure of the actual measured annual runoff by the Aral Hydrological Station to the long-term average annual value for the three headstreams of the Tarim River. decreased by billion m 3 compared with the long-term value for July. Specifically, the incoming water from the Hotan River, the Yarkand River and the Aksu River decreased by 42%, 40%, and 28%, respectively. By August 2009, only the Aksu River had supplied billion m 3 of water into the mainstream of the Tarim River. Fig. 6 shows the percentage departure of the actual measured annual runoff by the Aral Hydrological Station from the long-term average annual value for the three headstreams of the Tarim River. The average values in all years until the 1980s were less than the long-term average annual value. After the 1990s, the annual runoff was more than the long-term average annual value in all years except 2004, and had an increasing tendency. The annual amount of water flowing from the three headstreams into the mainstream of the Tarim River had a significant decreasing tendency, especially in 2007 and 2008, decreasing by an astonishing 29.3% and 37.2% of the long-term average annual value. Through thorough analysis of the hydrological regime of the Tarim River, since the year 2000, although the amount of incoming water into the three headstreams of the Tarim River showed little difference in the past nine years, the amount of water actually flowing into the mainstream showed large differences among these years, related to the peak, volume and duration of floods flowing into the mainstream of the Tarim River. Through statistical analysis of peak, volume and duration of different floods at the Aral Hydrological Station from 2000 to 2008 (Fig. 7), both the volume and duration of floods in 2007e2008 greatly deceased, compared with the previous several years. Without a definitely high discharge and duration of water flow at the convergence of the headstreams into the mainstream of the Tarim River, the water from the upper reach cannot be ensured to flow into the lower reach of the mainstream river in sufficient amounts. Flood peaks >800m 3 /s occurred in almost every year from 2000 to 2006, and those Fig. 7. Duration of different floods at the Aral Hydrological Station at the convergence of the three headstreams from 2000 to 2008.

6 Y. Chen et al. / Quaternary International 244 (2011) 264e >1000m 3 /s occurred yearly in 6 out of these 7 years. The duration of flood peaks >400m 3 /s in every year from 2000 to 2006 (except 2004) were all higher than that in 2007 and In 2004, a dry year with low flood peak and volume, the incoming water flowing into the three headstreams of the Tarim River was significantly lower than the long-term average annual value, which was due to the low amount of water flowing into the mainstream Analysis of the departure of runoff Linear fitting for the departure of runoff in a time sequence from 1957 to 2008 at the Aral Hydrological Station was conducted by using the least square method (Fig. 8). The departure of runoff at the Aral Hydrological Station alternates between positive and negative, showing an oscillating and decreasing tendency. Fig. 8a also shows that the years with positive departure were significantly more than those with negative departure before the 1970s. However, the situation changed after the 1970s, and the years with negative departure significantly increased. This shows that the annual runoff at the Aral Hydrological Station was lower than the long-term average annual value in most years after the 1970s. In addition, from the accumulative departure (Fig. 8b), the annual runoff of the mainstream decreased continuously from 1973 to 1976, oscillated in the following 13 years (1976e1988), decreased continuously again from 1988 to 1993 to a lower level of annual runoff of m 3, and declined in a step-like manner from 1993 to 2008 with a large fluctuating annual runoff. The decline from 2006 to 2008 was especially significant, from m 3 to m 3 with a total decrease in rate of 51% in these two years. 4. Causes of desiccation of the Tarim River and mitigating countermeasures 4.1. Constant increase in irrigated area in the headstream area In the Tarim River basin, the problems between ecology and production, as well as exploitation and protection are increasingly severe and are exacerbating the water crisis in the river basin. The contradiction between the ecology and the economy is quite conspicuous with regard to water resource exploitation in the Tarim River basin. The relationship between the water for production and that for ecological conservation, and the problem of contending for water between human beings and nature has not been sufficiently addressed. There are five autonomous prefectures and 4 divisions (bureaus) of the Xinjiang Production and Construction Corps in the Tarim River basin. The water consumption relationships between the headstreams and the mainstream, the upper and lower reaches, and the Corps and the locality are complicated. There are many problems with the combined utilization of surface water and ground water, and also with the water resource allocation in the river basin. The irrigated area in the headstream region is constantly increasing, and water waste is quite severe. Therefore the problem of secondary salinization of soil in the headstream area is conspicuous, and the water transferred to the mainstream continuously decreases. In addition to the headstream area s constant decrease, water consumption at the upper and middle reaches of the mainstream area of the Tarim River increase continuously, and arbitrary water usage from the river is common, thus accelerating the desiccation process. The direct cause of river desiccation is that the irrigated area in the Tarim River basin has increased constantly. According to statistical data, the irrigated area for the four headstreams and one mainstream of the Tarim River currently exceeds the originally approved irrigated area by up to 4000 km 2. If the irrigation quota in the Tarim River basin is assumed as m 3 /ha m 2, about 5.0 billion m 3 of water is needed for the additional irrigated area. By adding the water for originally planned irrigated area to the additional 1.23 million ha m 2, a total of nearly 20.0 billion m 3 of water is needed. The greatly increasing irrigated area not only consumes reserved water from comprehensive control of the Tarim River basin, and the exploited ground water, but also consumes water for the ecological use in the original river. The complications in water utilization make it difficult to ensure that a sufficient amount of water is available for ecological use in the mainstream of the Tarim River. Therefore, the desiccation of the Tarim River and the consequent ecological crisis will become increasingly obvious, and the realization of the planning targets for the Tarim River will be greatly impacted Water consumption in the upper and middle reaches of the mainstream is constantly increasing Fig. 8. Departure and accumulative departure of runoff from 1957 to While the water from the headstream area constantly decreases, the water consumption at the upper reach of the mainstream area of the Tarim River ceaselessly increases. Thus, the desiccation tendency is accelerated in the lower reach. From Fig. 9, the water flowing into the mainstream of the Tarim River was mainly consumed in the upper and middle reaches. The annual water consumption at these two reaches rose from 40.6e m 3 in the 1950se1960s to the current m 3. The ratio of the annual water consumption at these two reaches to the total incoming water increased from 72.2 to 76.7% in the 1950se1960s to the current 96.4% (Zhou, 1998). Water flowing into the mainstream has been consumed fully at the upper and middle reaches before it travels to the lower reaches. The water consumption in the upper reaches of the mainstream of the Tarim River has been consistently increasing since the 1950s, accelerating the desiccation trend of the lower reaches of the Tarim River. Through analysis and calculation of the water transfer to the lower reach of the Tarim River and the water consumption data per unit river length for each year from 2000 to 2008, the water consumption per unit river length at the upper, middle and lower reaches is respectively m 3,

7 270 Y. Chen et al. / Quaternary International 244 (2011) 264e271 Fig. 9. Ratio of the annual water consumption at upper, middle and lower reaches of the Tarim River m 3 and m 3. Thus, in order to cause the water head to reach the Qiala section, the Daxihaizi Reservoir and the Taitema Lake at the lower reach of the Tarim River, the required minimum discharge through the Alagan Hydrological Station is respectively m 3, m 3 and m 3. According to the amount of water flowing into the mainstream of the Tarim River from the three headstreams in the past 5 years, it would be difficult to return the river desiccation tendency to the state before the 1970s Construction of reservoirs in the mountain areas and desiccation The construction of reservoirs in the mountain areas in the Tarim River basin may bring new problems to the desiccation of the Tarim River. With the implementation of the Tarim River Control Project, a number of control reservoirs will be established in the headstream area. The reservoirs constructed will include 6 reservoirs: the Xiabandi Reservoir and the Aertashi Reservoir on the upper reach of the Yarkand River, the Wruwat Reservoir and the Yulongkash River Hydrojunction on the Kalakash River, and the Dashixia Reservoir and the Xiaoshixia Reservoir on the Aksu River. The combined reservoir capacity is billion m 3, accounting for about one-third of the incoming water. When these reservoirs are established in succession, they will have important functions for flood control, irrigation, and power generation, and bring about evident economic benefits. However, the water flowing into the mainstream of the Tarim River will be more limited. In addition, the reservoirs have the functions of storage adjustment and peak clipping, so, even if a certain extent of discharge is regulated to flow down, the expected objective to transfer water to the terminal lakes of the Tarim River will not be realized due to limited flood peak scale. For example, owing to the peak clipping function of the Wruwat Reservoir on the Kalakash River, the amount of water flowing into the mainstream of the Hotan River decreased greatly in 2007 and 2008, and the water from the Kalakash River flowing into the mainstream of the Hotan River was negligible up to August Fig. 10 shows the comparison of the discharge of flood peak in the large tributary of the Hotan River at the upper reach to the Kalakash River during the flood season at the Wruwat Hydrological Station. The longest durations of flood peaks >400 m 3 /s were 7 days and 10 days respectively in 2005 and 2006, no flood peak >400 m 3 /s occurred in 2007 and 2008, and the water flowing into the Hotan River decreased greatly. From this analysis the discharge through the Xiaojiake section at the convergence of the three headstreams must be more than 400 m 3 /s and last for at least 20 days for the water head to reach the Qiala section at the lower reach of the Tarim River. Therefore, the influence of the reservoir must be considered, and scientific evaluation must be conducted to evaluate further desiccation of the mainstream of the Tarim River due to the construction of reservoirs in the mountain areas, so as to strategically address the relationship between exploitation and protection. 5. Concluding remarks As the largest inland river in China, Tarim River plays a very important role in supporting the socio-economic system as well as supporting the vulnerable ecosystems in Xinjiang Province. However, the arid climate determines that the competition of water between natural ecosystems and human society is the basic characteristics of this inland river basin. Large-scale water exploitation in Tarim River in past decades have led to a great achievement in economic development, however, as a trade-off, the ecologic systems especially at the lower reaches of the mainstream has been largely deteriorated due to reduction, or even desiccation, of river flows. The desiccation of the Tarim River showed an accelerated trend in past 3 decades. Even though emergent ecological water diversion practices have achieved large effects in saving the severely degraded ecosystems, the huge withdrawal for irrigation at major oases of headstreams still puts great pressure on the ecological conservation in lower reaches of the mainstream. For sustainable development and a harmonized future with human and nature, water saving technologies should be widely practiced across the basin and scientifically insight of the water resources system, i.e. the basin scale hydrological cycle, are urgently needed for implementation of integrated river basin management (IRBM) in this largest inland river basin. Acknowledgments The research is supported by the National Basic Research Program of China (973 Program: 2010CB951003), Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX2-YW- Q10-3-4, KZCX2-YW-Q10-3) and West Light Foundation of The Chinese Academy of Sciences (XBBS200907). References Fig. 10. Discharge of flood peak in the large tributary of the Hotan River at the upper reach to the Kalakash River during the flood season at the Wruwat Hydrological Station from 2005 to Cao, J.F., Ye, X.Y., Wang, K.J., Jiang, J.Y., Effect of no-flow in the Lower Yellow River on groundwater formation and usage in areas along the banks. Frontiers of Earth Science in China 2 (4), 379e383. Chen, Yaning, Cui, Wangcheng, Li, Weihong, Zhang, Yuanming, Utilization of water resources and ecological protection in the Tarim River. Acta Grographica Sinica 58 (2), 215e222 (in Chinese).

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