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Li G.S.,Chinese Academy of Sciences | Li G.S.,CAS Institute of Remote Sensing | Li G.S.,University of Chinese Academy of Sciences | Qu J.J.,Chinese Academy of Sciences | And 4 more authors.
Terrestrial, Atmospheric and Oceanic Sciences | Year: 2013

To study the micro-meteorological effects of different underlying surfaces of structures to protect the Mogao Grottoes, we analyzed basic meteorological measurements collected at weather stations located in front of the grottoes, on top of the grottoes and in the artificial Gobi. The results show that the shelterbelts in front of the grottoes have a heat-retaining effect. The profile of average daily solar radiation in front of the grottoes forms a sharp peak and the profile in the Gobi forms a parabola, but these patterns vary in different seasons. The artificial Gobi was more susceptible to extremes in temperature and had a faster response and wider response range to ground temperature. The average monthly air temperature, average monthly relative humidity, and the average wind speed in the artificial Gobi tend to first decrease and then increase with measurement height. Copyright © 2005 TAO All right reserved. Source


Xie S.-B.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.-J.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.-J.,Gansu Center for Sand Hazard Reduction Engineering and Technology
Tiedao Xuebao/Journal of the China Railway Society | Year: 2013

Sand-control engineering practice will result in sand deposition inevitably. How will the thermal regime of underlying permafrost change after the ground surface has been covered with sandy sediments?No significant conclusions have been drawn currently. Therefore, utilizing thermistor temperature sensors and adopting the synchronization contrast observation method in the test field of Honglianghe sand-damaging sections in permafrost regions along the Qinghai-Tibet Railway, the thermal regime of permafrost lying underneath sand sediments of different thicknesses as the results of different sand-control measures taken along the Qinghai-Tibet Railway was studied. Both sand-block engineering projects situated in the outer-edge area with thick sand sediments and sand-fixing engineering projects situated in the inner-edge area with thin sand sediments were found to be able to make the ground temperature of underlying permafrost lower, seasonal thawing depths shorter, active layers thinner, freezing layers thicker and permafrost table higher. The maximum annual mean value of the permafrost temperature drop reached 0.3°C and the permafrost table rose by 0.4 m maximally. By mechanism analysis, changes of the thermal regime of permafrost after ground surface being covered with sand sediments were attributed mainly to high reflectivity and poor heat conductivity of sand layers. It is seen that sand sediments on ground surface are beneficial to improve the permafrost table and enhance subgrade stability in permafrost sections of the Qinghai-Tibet Railway. This has reference significance to other projects in similar zones. Source


Liu B.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.,Gansu Center for Sand Hazard Reduction Engineering and Technology | Ning D.,International Research and Training Center on Erosion and Sedimentation | And 3 more authors.
Aeolian Research | Year: 2014

A grain-size study was conducted on the surface sediments found east of Kumtagh Desert and its connected geomorphic units, such as the wadi, wetland, oasis, and alluvial fan. The frequency, cumulative curves, and scatter diagrams of four grain-size parameters, namely, the mean grain size, sorting, skewness, and kurtosis, were plotted to study the grain-size characteristics of each sediment. Multiple discriminant analyses were applied to distinguish the deposition environments. Results indicated large diversities in the sediments from different environments. The aeolian sediments from the sandy desert and the gobi land show uniform characteristics or homogeneous changes. The sand resources from the eastern part of the desert can be considered as the alluvial deposits from the southern Altyn Tagh Mountain carried by several erosion gullies. Meanwhile, the western Mingsha Megadune inherited sediments from the nearby Danghe River. The discriminant functions proposed by Sahu can distinguish the deposition process. However, these functions lose their accuracy when applied to heavily eroded aeolian and gobi sediments. © 2014. Source


Liu B.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.,Gansu Center for Sand Hazard Reduction Engineering and Technology | Kang S.,State Key Laboratory of Cryospheric science
Climate Research | Year: 2016

Four general circulation models (GCMs) under the moderate Representative Concentration Pathway (RCP) 4.5 emission scenario were used to evaluate the impact of climate change on monthly scale dune activity and desertification during the near future (2015-2035) in Anduo on the Tibetan Plateau (TP) of China. Dune activity was estimated by an improved index that uses the Penman-Monteith equation to account for comprehensive climate factors, including precipitation, air temperature, wind speed, humidity, and air pressure. Lower limits were used for the evapotranspiration values and the ratio of rainfall to evapotranspiration so that it was possible to calculate a dune activity index in the cold and dry winter months in the TP. The GCM outputs were transferred by statistical functions built from the control period (1966-2005), and the overlapping period of GCM projections and observations from 2006-2014 was used for error estimation. The results show that all GCMs captured the variation in dune activity well, although large differences in values were found. The statistical transferring of GCM outputs cannot reduce estimation error. The annual dune activity index is predicted to decrease by 7 to 9% during 2015-2035, implying that sand dunes will be easily stabilized in the future, but the 4 GCMs differ in January and February. If excessive surface disturbances can be controlled, the future environment in the studied area will be suitable for the reversal of the desertification trend, recovery of degraded land, and improvement of the living conditions for local herders. © 2016 The authors. Source


Xiao J.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Yao Z.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Qu J.,Gansu Center for Sand Hazard Reduction Engineering and Technology | Sun J.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute
Journal of Renewable and Sustainable Energy | Year: 2013

Optimal site selection for desert photovoltaic power plants is important to energy output and involves a multicriteria evaluation of many factors. This paper analyzes the factors influencing desert photovoltaic power station site selection and establishes an optimal site selection model for desert photovoltaic power plants using an analytic hierarchy process and geographic information system technology. We selected a typical desert area in northwestern China as the research location to test the model. Validation results were ideal, and the model successfully displayed the optimal site for desert photovoltaic power plants, from which the most suitable site for desert photovoltaic power plants could be selected. © 2013 AIP Publishing LLC. Source

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