Potential risks and challenges of climate change in the arid region of northwestern China

In the arid region of northwestern China(ARNC),water resources are the most critical factor restricting socioeconomic development and influencing the stability of the area’s ecological systems.The region’s complex water system and unique hydrological cycle show distinctive characteristics.Moreover,the intensified hydrological cycle and extreme climatic and hydrological events resulting from global warming have led to increased uncertainty around water resources as well as heightened conflict between water supply and water demand.All of these factors are exerting growing pressures on the socioeconomic development and vulnerable ecological environment in the region.This research evaluates the impacts of climate change on water resources,hydrological processes,agricultural system,and desert ecosystems in the ARNC,and addresses some associated risks and challenges specific to this area.The temperature is rising at a rate of 0.31
C per decade during 1961–2017 and hydrological processes are being significantly influenced by changes in glaciers,snow cover,and precipitation form,especially in the rivers recharged primarily by melt water.Ecosystems are also largely influenced by climate change,with the Normalized Difference Vegetation Index(NDVI)of natural vegetation exhibited an increasing trend prior to 1998,and then reversed in Xinjiang while the Hexi Corridor of Gansu showed the opposite trends.Furthermore,the desert-oasis transition zone showed a reduction in area due to the warming trend and the recent rapid expansion of irrigated area.Both the warming and intensified drought are threatening agriculture security.The present study could shed light on sustainable development in this region under climate change and provides scientific basis to the construction of the“Silk Road Economic Belt”.

Upper mantle convection beneath northwest China and its adjacent region driven by density anomaly

We assume that the density anomalies, which are transformed from seismic tomography data, are corresponding to temperature distribution in a convective mantle. We take density anomalies as the driving force for mantle convection and solve the basic equation with given boundary conditions in a wave-number domain by using the FFT arithmetic. Using the physical model of upper mantle convection and the seismic tomography data supplied by XU et al, we calculated upper mantle convection beneath northwestern China and adjacent region. The flow patterns in the upper mantle show that there are upward and divergent flows in the basin regions, such as Tarim, Qaidam, Junggar and Kazakhstan, where the lithosphere is thin. There are downward and convergent flows in the mountain regions, such as Tianshan, Kunlun and Qilian, where the lithosphere is thick. In addition, because of the divergent flow under the Tarim Basin the upper mantle material in this region is driven southward to the north part of Tibetan Plateau and northward to Tianshan Mountain. Maybe, it is one of the reasons for the recent uplift of the Tianshaa Mountain.

Modeling demand/supply of water resources in the arid region of northwestern China during the late 1980s to 2010

Water demand increases continuously with an increasing population and economic development. As a result, the difference between water supply and demand becomes a sig- nificant issue, especially in arid regions. To figure out the utilization of water resources in the arid region of northwestern China （ARNWC）, and also to provide methodologies to predict the water use in future, three models were established in this study to calculate agricultural irri- gation, industrial and domestic water use in the ARNWC from the late 1980s to 2010. Based on river discharges in the region, the supply and demand of water resources at the river basin level were analyzed. The results indicated that agricultural irrigation demand occupies more than 90% of the total water use in the ARNWC. Total water demand increased from 31.97 km3 in the late 1980s to 48.19 km3 in 2010. Most river basins in this arid region were under me- dium and high water stress. Severe-risk river basins, such as the Shiyang river basin and the eastern part of the northern piedmont of the Tianshan Mountains, were found in this region. It was revealed that the water supply became critical from April to May, which was the season of the lowest water supply as determined by comparing monthly water consumption.

Quantifying the impact of mountain precipitation on runoff in Hotan River, northwestern China

It is of great significance to quantitatively assess the impact of mountain precipitation on inland river runoff in data scarce regions.Based on the corrected TRMM precipitation and runoff data,a variety of statistical methods were used to identify which areas of precipitation have an important impact on runoff in the Hotan River Basin,and to evaluate the effects that precipitation changes have on runoff at low,mid,high,and extremely high altitudes of mountainous areas.The results showed that:1)From 1998 to 2015,the annual runoff showed a fluctuating upward trend with a rate of 11.21×10^8 m^3/10 a(P<0.05).Runoff in every season also had an increasing trend,with summer runoff the most significant at a rate of 6.09×10^8 m^3/10 a.2)The annual runoff and precipitation changes had certain synchronization,with a correlation coefficient of 0.45(P<0.05).Among them,the correlations between precipitation and runoff changes were highest at low and mid-altitudes,with coefficients of 0.62 and 0.55,respectively(P<0.05).3)65.95%of the regional precipitation at low altitudes and 48.34%at high altitudes were significantly correlated with runoff(P<0.05),while only 38.84%and 26.58%of regional precipitation levels at mid-and extremely high altitudes were significantly correlated with runoff.4)The annual precipitation change in the basin was 1%,which would cause the annual runoff to change by 0.24%.In 1998-2015,the change of annual runoff caused by precipitation change at high altitudes was largest at a rate of−6.01%;the change rates of annual runoff caused by precipitation change in the low,mid-,and extremely high altitudes were−3.66%,−3.62%,and−3.67%,respectively.The results have significant scientific guidance for water resource management in arid basins.

Forest Fires and Prevention Strategies in Northwestern Region of China

The paper described the natural conditions and forest types in Northwestern Region of China. Most forests in the region are distributed in subalpine areas. It is important to protect the existent forests in the region for maintaining ecological balance. According to the statistics results of 1991~2000, the paper analyzes the forest fires distribution and fire severity. Annually the numbers of forest fires range from 52 to 240. The incidence rate of forest fires in Northwestern Region is under 0.33 per t...

The Largest Copper, Aluminum Wire and Cable Production Enterprise in the Northwestern Region Lands in Qinghai

The largest wire and cable production enterprise in the northwestern region-Qinghai Xingming Electric Power Material Co.,Ltd.has been officially put into production,meaning that Qinghai will be able to selfproduce medium and high voltage or even EHV crosslinked power cables and develop and produce differentiated new products such as high-altitude cold-resistant photovoltaic