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Progress on research and mitigation of wind-blown sand risk in Dunhuang Singing Sand Mountain and Crescent Spring Scenic area,China

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Research in Cold and Arid Regions 2023年第3期15卷 113-121页

作者： BenLi Liu KeCun Zhang jianjun qu HaiJiang Li QingHe Niu ZhiShan An YingJun Pang LiHai Tan GenSheng Yang Laboratory of Ecological Safety and Sustainable Development in Arid Lands/Research Station of Gobi Desert Ecology and Environment in Dunhuang Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) GuangzhouGuangdong 51145China Administrative Office of the Dunhuang Singing Sand Mountain and Crescent Spring National Scenic Spot DunhuangGansu 736200China Institute of Desertification Studies Chinese Academy of ForestryBeijing 100091China

The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang,Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global *** scenic area underwent a 30-year transformation,i.e.,from a severe sand risk with spring water threatened by sand burial due to dune deformation,to restoration of the original sand flow field and mitigation of the sand burial *** current paper summarizes the research on the intensive monitoring of the dynamic change of star dunes near the spring,observation of wind and sand flow movement,and then restoring the harmonic vibration of the sand particles(singing sand)that were previously *** existing and prospective impacts of anthropogenic and natural forces on the deformation of the sand dunes are investigated by integrated methods,guiding the implementation of mitigating measures with significant ameliorative *** to common sand control practices that aim to reduce wind speed and stop blown sands,our research highlights the importance of maintaining the natural wind flow field in stabilizing surrounding *** mitigation measures consist of removing excessive vegetation and newly constructed buildings to recover the original wind flow field and sand transport *** research and mitigation efforts ensure the scientific protection and restoration of the special desert landform,and contribute to the mutual enhancement of the conservation and exploitation of this desert scenic spot and similar sites.

关键词： Singing Sand Mountain Crescent Spring Wind-blown sand problem Wind flow field Star dune

基于大机捣固模式的轨道质量保质期预测方法研究

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铁道学报 2019年第8期41卷 117-122页

作者：曲建军中国铁道科学研究院集团有限公司基础设施检测研究所

以提升大型捣固机械(以下简称大机)维修的经济化、效率化应用为目标,基于大量轨道几何历史检测和维修数据,提出一种预测不同捣固模式轨道质量保质期的方法。分析捣固前、后的大机捣固质量指数MTQI在不同大机捣固模式下的函数关系,得到... 详细信息

以提升大型捣固机械(以下简称大机)维修的经济化、效率化应用为目标,基于大量轨道几何历史检测和维修数据,提出一种预测不同捣固模式轨道质量保质期的方法。分析捣固前、后的大机捣固质量指数MTQI在不同大机捣固模式下的函数关系,得到系列捣固效果函数。利用灰色GM(1,1)预测技术建立MTQI随通过时间及通过总重发展的非线性预测模型,将其与捣固效果函数结合,可应用于不同大机捣固模式下轨道质量保质期的预测和捣固模式的比选。既有线及重载线路的实例证明,本文提出的轨道质量保质期预测方法有助于轨道维修部门比选最佳捣固维修模式,可为我国有砟轨道捣固维修计划选择提供科学、经济的决策参考。

关键词：轨道几何检测数据预防性维修捣固模式捣固效果函数 GM(1,1)预测理论捣固保质期

Analyses on the Types,Distributions and Characteristics of Vegetation and Soil along Qinghai-Tibet Railway

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Meteorological and Environmental Research 2013年第9期4卷 15-18页

作者： Shengbo Xie jianjun qu Key Laboratory of Desert and Desertification/Dunhuang Gobi and Desert Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Gansu Center for Sand Hazard Reduction Engineering and Technology

[Objeective] The research aimed to study the types, distributions and characteristics of vegetation and soil along Qinghai -Tibet Rail- way. [ Method]Types, distributions and characteristics of vegetation and soil along Qinghai -Tibet Railway were studied by field investigation meth- od. [Result] The vegetation along Qinghai -Tibet Railway was dominated by alpine grassland and meadow, while the soil was dominated by alpine steppe soil and meadow soil corresponding along the railway. They both concentrated distnbutions at the section from Kunlun Mountain to Nyainqen- tanglha Mountain. [ Conclusion] The research could provide the basis for disaster control and resource development of Qinghai-Tibet Railway.

关键词： Qinghai-Tibet Railway Vegetation Soil China

Sheltering effect of punched steel plate sand fences for controlling blown sand hazards along the Golmud-Korla Railway:Field observation and numerical simulation studies

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Journal of Arid Land 2022年第6期14卷 604-619页

作者： ZHANG Kai TIAN Jianjin qu jianjun ZHAO Liming LI Sheng College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Sand fences made of punched steel plate(PSP)have recently been applied to control wind-blown sand in desertified and Gobi areas due to their strong wind resistance and convenient in situ ***,few studies have assessed the protective effect of PSP sand fences,especially through field *** study analyzes the effects of double-row PSP sand fences on wind and sand resistance using field observations and a computational fluid dynamics(CFD)numerical *** results of field observations showed that the average windproof efficiencies of the first-row and second-row sand fences were 79.8%and 70.8%,***,the average windproof efficiencies of the numerical simulation behind the first-row and second-row sand fences were 89.8%and 81.1%,*** sand-resistance efficiency of the double-row PSP sand fences was 65.4%.Sand deposition occurred close to the first-row sand fence;however,there was relatively little sand on the leeward side of the second-row sand *** length of sand accumulation near PSP sand fences obtained by numerical simulation was basically consistent with that through field observations,indicating that field observations combined with numerical simulation can provide insight into the complex wind-blown sand field over PSP sand *** study indicates that the protection efficiency of the double-row PSP sand fences is sufficient for effective control of sand hazards associated with extremely strong wind in the Gobi *** output of this work is expected to improve the future application of PSP sand fences.

关键词： punched steel plate sheltering effect field observations computational fluid dynamics numerical simulation windproof efficiency

Glacier extraction based on ASAR,DEM and texture feature of ASAR using SVM in the Western Qilian Mountains,Northwest China

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Research in Cold and Arid Regions 2012年第3期4卷 195-200页

作者： JunZhan Wang jianjun qu WeiMin Zhang Dunhuang Gobi and Desert Ecology and Environment Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China Gansu Center for Sand Hazard Reduction Engineering and Technoogy Lanzhou Gansu 730000 China

This paper is focused on the method for extracting glacier area based on ENVISAT ASAR Wide Swath Modes （WSM） data and digital elevation model （DEM） data, using support vector machines （SVM） classification method. The digitized result of the glaci- er coverage area in the western Qilian Mountains was extracted based on Enhanced LandSat Thematic Mapper （ETM＋） imagery, which was used to validate the precision of glacier extraction result. Because of similar backscattering of glacier, shadow and wa- ter, precision of the glacier coverage area extracted from single-polarization WSM data using SVM was only 35.4%. Then, texture features were extracted by the grey level co-occurrence matrix （GLCM）, with extracted glacier coverage area based on WSM data and texture feature information. Compared with the result extracted from WSM data, the precision improved 13.2%. However, the glacier was still seriously confused with shadow and water. Finally, DEM data was introduced to extract the glacier coverage area. Water and glacier can be differentiated because their distribution area has different elevations; shadow can be removed from the classification result based on simulated shadow imagery created by DEM data and SAR imaging parameters; finally, the glacier coverage area was extracted and the precision reached to 90.2%. Thus, it can be demonstrated that the glacier can be accurately semi-automatically extracted from SAR with this method. The method is suitable not only for ENVISAT ASAR WSM imagery, but also for other satellite SAR imagery, especially for SAR imagery covering mountainous areas.

关键词： glacier ASAR DEM texture feature

Overall efficiency of a V-shaped nylon net fence in preventing sand damage to the Mogao Grottoes

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Research in Cold and Arid Regions 2012年第2期4卷 163-174页

作者： GuoShuai Li jianjun qu WanFu Wang Wei Yang Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhouGansu 730000China The Conservation Institute of Dunhuang Academy DunhuangGansu 736200China The Economic Research Institute of Hong Kong and Macao Special Administrative Region Jinan UniversityGuangzhouGuangdong 510632China

A V-shaped nylon net fence installed in 1990 on top of the Mogao Grottoes is shown to be effectively resisting aeolian sand damage to the grottoes. The structure guides and causes deposition of sand from westerly wind （the primary hard wind）, but to some extent hinders the inverse function of easterly wind carrying sand away from the grottoes toward Mount Mingsha. The gobi side by the fence experiences higher wind speed, so that on which are easily formed undercutting pits, and the deposited sands on it generally form double-peak structures due to abundant sand sources. If the earth surface characteristics in gobi areas by both sides of the fence are quite varied, the erosion and deposition features of the accumulating sand section are similar in different seasons; however, if the earth surface characteristics are similar, the features become irregular in different seasons. Sand depositions with long slope feet are formed along the south and north sides of V-shaped nylon net fence. Disrupted by strong westerly wind and northwesterly wind, sand accumulations by north of the fence are in form of single peaks. Although the operation duration of the V-shaped nylon net fence has exceeded its design life （10 years）, our observations indicate that it is still effective in reducing wind-driven sand damages to the Mogao Grottoes, so it should not be withdrawn.

关键词： nylon net sand prevention gobi Mogao Grottoes

Formation and ecological response of sand patches in the protection system of Shapotou section of the Baotou-Lanzhou railway,China

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Journal of Arid Land 2024年第2期16卷 298-313页

作者： DUN Yaoquan qu jianjun KANG Wenyan LI Minlan LIU Bin WANG Tao SHAO Mei Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environmental Sciences Northwest UniversityXi'an 710100China Zhongwei Works Section of China Railway Lanzhou Bureau Group Company Limited Zhongwei 755000China

The development of bare patches typically signifies a process of ecosystem *** the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses a threat to both stability and ***,there is limited knowledge regarding the morphology,dynamic changes,and ecological responses associated with these sand ***,we analyzed the formation and development process of sand patches within the protection system and its effects on herbaceous vegetation growth and soil nutrients through field observation,survey,and indoor analysis *** results showed that sand patch development can be divided into three stages,i.e.,formation,expansion,and stabilization,which correspond to the initial,actively developing,and semi-fixed sand patches,*** average dimensions of all sand patch erosional areas were found to be 7.72 m in length,3.91 m in width,and 0.32 m in *** actively developing sand patches were the largest,and the initial sand patches were the *** the stage of formation and expansion,the herbaceous community composition changed,and the plant density decreased by more than 50.95%.Moreover,the coverage and height of herbaceous plants decreased in the erosional area and slightly increased in the depositional lobe;and the fine particles and nutrients of soils in the erosional area and depositional lobe showed a decreasing *** the stabilization phases of sand patches,the area from the inlet to the bottom of sand patches becomes initially covered with *** and 0-2 cm surface soil condition improved in the erosional area,but this improvement was not yet evident in the depositional *** such as disturbance,climate change,and surface resistance to erosion exert notable influences on the formation and dynamics of sand *** results can provide evidence for the future treatment of sand patches and the management of the pro

关键词： railway protection system sand patch morphology vegetation characteristic soil property

Methods for calculating glacier area and length in a mountainous area based on remote-sensing data and a digital elevation model

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Research in Cold and Arid Regions 2010年第4期2卷 298-304页

作者： JunZhan Wang YouJing Zhang WeiMin Zhang jianjun qu Chen Chen Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China School of Earth Sciences and Engineering HoHai University Nanjing Jiangsu 210098 China Institute Geological Survey of Jiangsu Province Nanjin Jiangsu 210018 China

In a mountainous region, the glacier area and length extracted form the satellite imagery data is the projected area and length of the land surface, which can’t be representative of the reality; there are always some errors. In this paper, the methods of calculating glacier area and length calculation were put forward based on satellite imagery data and a digital elevation model (DEM). The pure pixels and the mixed pixels were extracted based on the linear spectral un-mixing approach, the slop of the pixels was calculated based on the DEM, then the area calculation method was presented. The projection length was obtained from the satellite imagery data, and the elevation differences was calculated from the DEM. The length calculation method was presented based on the Pythagorean theorem. For a glacier in the study area of western Qilian Mountain, northwestern China, the projected area and length were 140.93 km2 and 30.82 km, respectively. This compares with the results calculated by the methods in this paper, which were 155.16 km2 and 32.11 km respectively, a relative error of the projected area and length extracted from the LandSat Thematic Mapper (TM) image directly reach to -9.2 percent and -4.0 percent, respectively. The calculation method is more in accord with the practicality and can provide reference for some other object’s area and length monitoring in a mountainous region.

关键词： area length remote sensing glacier

Mechanisms of the formation of wind-blown sand hazards and the sand control measures in Gobi areas under extremely strong winds along the Lanzhou-Xinjiang high-speed railway

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Science China Earth Sciences 2023年第2期66卷 292-302页

作者： jianjun qu Tao WANG Qinghe NIU Benli LIU Lihai TAN Qingjie HAN Yang GAO Jianhua XIAO Key Laboratory of Desert and Desertification/Dunhuang Gobi and Desert Ecology and Environment Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou511458China

The Lanzhou-Xinjiang high-speed railway(HSR)traverses areas of the Gobi Desert where extremely strong winds are *** strong winds cause sand/gravel hazards,an unaddressed issue that often seriously compromises the safe operation of the *** paper studies the mechanisms leading to wind-blown sand hazards and the outcomes of sand control projects in these *** main findings are as follows:(1)Cold northern airflows over the Tian Shan mountain range are accelerated by the wind tunnels and downslope effect as they pass over complex terrain comprising passes,gullies,and proluvial ***,the wind intensity often increases two-to threefold,creating frequent high-speed winds that lead to severe sand damage along the HSR.(2)In the Gobi areas with extremely strong winds,sand grains can be lifted as high as 9 m from the ground into the air,far higher than in other areas of the *** sand transport rate decreases exponentially with increasing *** wind speed and particle size determine saltation *** particles and stronger winds provide the particles with a higher kinetic energy as they collide with the *** the wind zones of Baili and Yandun,the analysed study areas,the saltation layer height of wind-blown sand/gravel exceeds 3 and 2 m,respectively.(3)Based on the above findings,recently emerging sand control materials,suitable for the areas of interest,were screened and ***,under the proposed principle of‘supplementing blocking with trapping’,a comprehensive sand control measure was established,featuring sandblocking belts comprised of multiple rows,and high,vertical sand-trapping installations with a large grids *** installed system showed a high efficacy,reducing sand transport rate by 87.87%and significantly decreasing the deposition of sand along a trial section of the HSR.

关键词： Gobi areas with extremely strong winds Wind-blown sand hazards Complex terrain Sand/gravel flow Wind-blown sand control

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