Changchun Xu

Progress, Challenges and Prospects of Eco-Hydrological Studies in the Tarim River Basin of Xinjiang, China

Eco-hydrological research in arid inland river basins has been a focus of geologists and ecologists as it is crucial for maintaining the sustainable development of socio-economy, particularly in ecologically vulnerable areas. Based on the research work carried out in the Tarim River basin of Xinjiang, northwestern China, this paper summarizes synthetically the climate change and associated responses of water resources in the mountainous area, land use and land cover in the oasis, and plants responding to environmental stresses in the desert area of the river basin. Research gaps, challenges, and future perspectives in the eco-hydrological studies of the Tarim River basin are also discussed.

Responses of Surface Runoff to Climate Change and Human Activities in the Arid Region of Central Asia: A Case Study in the Tarim River Basin, China

Based on hydrological and climatic data and land use/cover change data covering the period from 1957 to 2009, this paper investigates the hydrological responses to climate change and to human activities in the arid Tarim River basin (TRB). The results show that the surface runoff of three headstreams (Aksu River, Yarkant River and Hotan River) of the Tarim River exhibited a significant increasing trend since 1960s and entered an even higher-runoff stage in 1994. In the contrary, the surface runoff of Tarim mainstream displayed a persistent decreasing trend since 1960s. The increasing trend of surface runoff in the headstreams can be attributed to the combined effects of both temperature and precipitation changes during the past five decades. But, the decreasing trend of surface runoff in the mainstream and the observed alterations of the temporal and spatial distribution patterns were mainly due to the adverse impacts of human activities. Specifically, increasingly intensified water consumption for irrigation and the associated massive constructions of water conservancy projects were responsible for the decreasing trend of runoff in the mainstream. And, the decreasing trend has been severely jeopardizing the ecological security in the lower reaches. It is now unequivocally clear that water-use conflicts among different sectors and water-use competitions between upper and lower reaches are approaching to dangerous levels in TRB that is thus crying for implementing an integrated river basin management scheme.

Assessment of meteorological disasters based on information diffusion theory in Xinjiang, Northwest China

Data of flood, drought, hailstorms, and low temperature events in Xinjiang from 1949 to 2012 were analyzed with the diffusion method to assess the risk of the most common types of disasters in Xinjiang. It was proved that the frequency and intensity of meteorological disasters of the study area showed an increasing trend associated with global warming. Among the four types of disasters, surpass probability of drought was the largest, followed by hailstorm, low temperature and flood in turn. Moreover, the wavelet method analysis revealed that greater oscillations had occurred since 2000, which may be associated with the occurrence of extreme climatic changes. The spatial distribution of frequencies reveals that the northern slope of Tianshan Mountains is a multiple disaster area, the southern slope of Tianshan is the area where more floods and hailstorms occur, and the west of Turpan-Hami Basin is the area wind is prevalent. The relationships between disaster-affected areas and corresponding meteorological and socio-economic indexes were also analyzed. It indicated that there were significant positive correlations between the areas affected and the most meteorological and socio-economic indicators except the grain acreage.

Climate System in Northwest China

A comparative analysis for detecting temperature and precipitation changes in the period 1960–2010 was conducted using data from 74 meteorological stations in China’s arid northwest. Significant increasing trends (P < 0.01) were revealed through the investigation, showing rates of 0.343 °C/10a and 6.07 mm/10a, which is higher than the global average. The winter temperature rate increased 0.486 °C/10a, while the summer temperature changed at a rate of 0.232 °C/10a. However, although precipitation increased 2.51 mm/10a in summer, it slowed in winter to a rate of 1.16 mm/10a. Regionally, the highest increasing rates of temperature and precipitation occurred in northern Xinjiang, and the lowest rates were recorded in southern Xinjiang and the Hexi Corridor. We found that, among the four seasons, winter saw the greatest temperature changes. We also found that the winter temperature in this region had a strong association with the Siberian High (correlation coefficient: R = − 0.715) and greenhouse gas emissions (R = 0.51).