Climate Change and Water Manage to the Oasification and Aeolian Desertification in Arid Region of China

Abstract

The temperature in arid region of China has been volatile risen over the past 60 years, with the warming range as high as 0.34℃/10a, nearly three times that of the global average.  There were seasonal and spatial differences in the amplitude of temperature variation.  The warming is the most obvious at 0.50℃/10a in winter and the smallest at 0.27℃/ 10a in spring. During  the last 60 years, the annual precipitation has shown a weak upward trend, which the increase in summer was the largest at 2.50 mm/10a and in winter was the smallest at 1.20 mm/10a.  Inland river flow is a barometer of climate change, which accounting for more than 85% of the total water resources in arid region of China.  The changes of climate warming, glacier retreat and melting of ice and snow have an important impact on the spatial and temporal changes of river flow, brought about the mountainous runoff raised.  Along with the better water supply conditions, the positive result is the expansion of artificial oasis (oasification) and the negative result is the aeolian desertification development.

Oasification is the transition process from desert to oasis in arid region resulted from human and natural factors.  Aeolian desertification is land degradation through wind erosion mainly resulted from the human impacts in arid, semiarid and sub-humid regions of China.  The expansion of aosification is always along with the menace of aeolian desertification.  There are 65% of the aosification transformed from no-aosis area and 35% came from natural oasis by cultivation, which means that the aosification is the process of reclaim desert land and natural oasis changed to artificial oasis.  The area of aeolian desertification mainly distribute over the periphery of oasis-desert and the middle and lower reaches of endorheic river.  It can be said that the aosification is the development process from natural ecosystems to artificial ecosystems which extended the living space to human being.  However, the low level or disorder aosification management can decrease the stability of the oasis and cause oasis degradation with the reduction or loss of land productivity, often can trigger a series of ecological problems such as river break, lakes shrinking, vegetation degradation, soil erosion and aeolian desertification.  Oasification enlarged and intensively managed areas of farming land mostly, which needs more and more water resources, so that some areas of transitional zone of oasis-desert and of lower reaches of endorheic river evolved into aeolian desertification because of the water shortage.  

Finally, we propose a suitable dimensions of oases with different water consumption characteristics based on the construction of multi-objective balance methods and mathematical models for healthy development of aosification and prevention of aeolian desertification in arid region of China.

Keywords: Water Manage, Oasification, Aeolian Desertification, Arid region of China