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Journal of Arid Land 2015年第6期7卷 755-764页

作者： LI Jinchang LIU Haixia su zhizhu FAN Xiaohui State Key Laboratory of Earth surface Processes and Resource Ecology Beijing Normal University Institute of Loess Plateau Shanxi University Historical Culture School Shanxi University

Wind activity is proved to have significant impacts on aeolian desertification. Clarifying the fluctuations and change trend of wind velocity is important for understanding their influence on aeolian desertification. In this study, we used a dataset of wind velocities collected from 93 meteorological stations across northern China from 1957 to 2011 to analyze the changes in wind activity during this period. We tested the monotonic and step（abrupt） trends for annual and seasonal data of mean wind velocity by using Mann-Kendall and Mann-Whitney tests, respectively. The results indicated that the annual mean wind velocity decreased by 0.83 m/s from 1957 to 2011. The decreasing trends were also significant（P〈0.01） for each season. The magnitude of the decrease was smallest in the east of northern China and largest in the west of northern China, and the most remarkable decrease occurred in the northwest of northern China. Abrupt decreases in annual and seasonal mean wind velocities occurred in the mid-1980 s, which was consistent with the changes in aeolian desertification since the mid-1980 s in northern China. As revealed by our study, although both modern aeolian desertification and ecosystem rehabilitation are affected by human activities to some extent, they are also likely to be strongly controlled by climate change, especially by wind activity.

关键词： wind velocity monotonic trend step trend aeolian desertification northern China

Reconstruction of the spatial patterns of desert/loess boundary belt in North China during the Holocene

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Chinese Science Bulletin 2001年第12期46卷 969-975页

作者： JIN Heling DONG Guangrong su zhizhu suN Liangying Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China Shapotou Desert Research and Experiment Station Chinese Academy of SciencesLanzhou 730000China Institute of Global Environment Research Chinese Academy of SciencesXi’an 710054China

The desert/loess boundary belt is the transitional region between desert and loess, where aeolian sand and loess interlock in space and alternate in time. It, being seriously unstable in space-time, sensitive to climatic changes and with fragile ecological environment, is an ideal region for studying the global climate change. There are deposi-tional sequences of paleosol with sub-horizontal interbedded aeolian sand and loess, and the stratigraphical evidences show that there widely exist 3-4 layers paleosol in sand lands of northeastern China, 4-5 layers in Mu Us Sandy Land and Hunshandake Sandy Land, more than 4 layers in the Qinghai Lake region and the Gonghe Basin of Qinghai Province during the Holocene. These indicate that the desert has experienced several times of extending and compacting, along with which the desert/loess boundary belt vibrated. It possesses good coherence with global climate change and eustasy. The coherence shows that the monsoon change in East Asia is the primary driving

关键词： Holocene desert/loess boundary belt spatial pattern.

Composition, origin and weathering process of surface sediment in Kumtagh Desert, Northwest China

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Journal of Geographical Sciences 2011年第6期21卷 1062-1076页

作者： XU Zhiwei LU Huayu ZHAO Cunfa WANG Xianyan su zhizhu WANG Zhenting LIU Hongyi WANG Lixin LU Qi School of Geographic and Oceanographic Sciences the MOE Key Laboratory of Coast and Island Development Nanjing University Nanjing 210093 China Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China College of Earth and Environmental Sciences Lanzllou University Lanzhou 730000 China Lanzhou Institute of Arid Meteorology China Meteorological Administration Lanzhou 730020 China

Kumtagh Desert is one of the eight biggest deserts in China, but poorly investigated before our interdisciplinary study because of the difficulty of access. In this paper, 33 representative surface sediment samples were collected from the Kumtagh Desert and analyzed in the laboratory to obtain heavy mineral components and geochemical element contents. Results show that various kinds of heavy minerals are present in these samples, with high levels of epidote and hornblende. Si and AI take up a large part of chemical composition. Compared with the average composition of geochemical elements of the upper continental crust （UCC）, except Si and Ca, all elements are depleted to a certain degree; Fe, Mg, Ca, P, Ti and Mn have high correlation coefficients in their contents. The mineral and geochemical composition of the Kumtagh Desert sediments have a similarity with that of rocks of Altyn Tagh Mountains, and the surface sediments of the alluvial/diluvial fans around the Altyn Tagh Mountains and that of the Taklamakan Desert, indicating that one major source of the Kumtagh Desert sediments is located in the Altyn Tagh Mountains. Alluvial deposits and lake sediments in Aqik valley and lower reaches of Shule River are prone to be eroded and transported by the strong northeasterly wind into the Kumtagh Desert, forming another source of the desert deposits. An A-CN-K ternary diagram shows that a weak degree chemical weathering by the loss of Na and K occurred in these sediments, whereas A-CNK-FM ternary diagram suggests that Fe and Mg have undergone a significant chemical differentiation. Physical weathering processes cause easy erosion and enrichment in fine particles for mafic minerals, thus coarse desert sand particles can be relatively depleted in Fe and Mg. The mineral and geochemical composition of sediments in arid regions experiencing less chemical weathering are mostly affected by physical weathering.

关键词： minerals geochemical elements sediment provenance weathering process Kumtagh Desert

气候变化背景下卡拉麦里国家公园蒙古野驴适宜生境脆弱性评价

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兽类学报 2024年第3期44卷 287-296页

作者：高帅帅胡杨邵长亮蒋丽伟张于光苏志珠吴波李佳中国林业科学研究院生态保护与修复研究所北京100091 山西大学环境与资源学院太原030006 新疆林业学校乌鲁木齐830026 新疆卡拉麦里山有蹄类野生动物自然保护区管理中心昌吉831100 国家林业和草原局林草调查规划院北京100714 中国林业科学研究院森林生态环境与自然保护研究所北京100091 山西大学历史文化学院太原030006

评估气候变化背景下蒙古野驴(Equus hemionus)适宜生境脆弱程度,是卡拉麦里国家公园制定适应性保护对策的关键和基础。本文筛选207个蒙古野驴分布点位以及9个环境变量,在BIOMOD2平台上利用其10种物种分布模型评估当前和未来2050s(2041—... 详细信息

评估气候变化背景下蒙古野驴(Equus hemionus)适宜生境脆弱程度,是卡拉麦里国家公园制定适应性保护对策的关键和基础。本文筛选207个蒙古野驴分布点位以及9个环境变量,在BIOMOD2平台上利用其10种物种分布模型评估当前和未来2050s(2041—2070年)、2080s(2071—2100年)气候变化背景下蒙古野驴适宜生境脆弱程度。结果表明:(1)在BIOMOD2平台的10种模型中,随机森林(RF)模拟效果最好,表面分布区分室模型(SRE)评分最低;组合模型的真实技巧统计值(TSS)为0.939,受试者工作特征曲线下面积(AUC)为0.996,表明平台模拟结果相对可靠;(2)年平均气温和最冷季平均气温是影响蒙古野驴适宜生境分布的主要因素;(3)蒙古野驴当前适宜生境主要分布在卡拉麦里国家公园的北部和中部,以及216国道两侧;到2080s(SSP370),主要分布在国家公园东部,适宜生境面积较当前减少68.8%。本研究利用BIOMOD2平台提供的组合模型的模拟结果,分析气候变化背景下蒙古野驴适宜生境的动态变化,计算卡拉麦里国家公园在当前和未来气候变化背景下蒙古野驴适宜栖息地的覆盖程度,为国家公园保护蒙古野驴提供适应性保护对策。

关键词：濒危物种 BIOMOD2 脆弱性评价保护对策气候庇护所

Discovery of Ordos Cretaceous dune rock and its significance

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Chinese Science Bulletin 1999年第22期44卷 2102-2106页

作者： Xiaoze Li Guangrong Dong Heling Jin zhizhu su Yuanping Wang Chinese Acad Sci Desert Res Inst Lanzhou 730000 Peoples R China Chinese Acad Sci State Key Lab Loess & Quaternary Xian 710054 Peoples R China

It has been found that there existed quite a large quantity of dune rocks in the red sandstone of the Zhidan Group of Ordos Cretaceous strata. Their sedimentary structure, grain size and micro-shape of sand grains show an obvious aeolian features. Both the temporal and spatial distribution and sedimentary characteristics of these dune rocks suggest that probably

关键词： Ordos dune rock significance.

Characterizing changes in ecosystem service values in China's eastern Loess Plateau

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Research in Cold and Arid Regions 2015年第3期7卷 272-281页

作者： JinChang Li HaiXia Liu zhizhu su Yong Liu YongGang Yang Institute of Loess Plateau Shanxi University Historical Culture School Shanxi University

Human activities such as the implementation of ecological protection projects and expansion of construction land can cause complex land use changes that affect ecosystem service values （ESV）. In this study, we investigated changes in ESV in response to land use changes in Ningwu County, in eastern Loess Plateau of China. Our aim is to provide guidance for sustainable land use planning in this region. We used remote sensing to evaluate land use changes, and applied a fast, proxy-based method for evaluating ESVat three points in time： 1990, 2000, and 2010. More than 89% of the total ESV in Ningwu County was attributable to woodland and grassland. The ESV in western mountain areas show the greatest increase from 1990 to 2010, but ESV decreased the most in the low-elevation northeastern area of flat terrain These tradeoffs led to a slight net decrease （1.0%） in Ningwu County＇s total ESV. Although the decline in ESV was relatively low compared to the rate of economic growth, total ESV was much lower than global and national average levels at the end of the study period.

关键词： ecosystem service values land use changes ecological protection projects remote sensing Ningwu County

Land use and land cover change processes in China's eastern Loess Plateau

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Research in Cold and Arid Regions 2015年第6期7卷 722-729页

作者： JinChang Li HaiXia Liu Yong Liu zhizhu su ZiQiang Du Institute of Loess Plateau Shanxi University Historical Culture School Shanxi University

Using Landsat remote sensing images, we analyzed changes in each land use type and transitions among different land use types during land use and land cover change （LUCC） in Ningwu County, located in the eastern Loess Plateau of China, from 1990 to 2010. We found that grassland, woodland, and farmland were the main land use types in the study area, and the area of each type changed slightly from 1990 to 2010, whereas the area of water, construction land, and unused land increased greatly. For the whole area, the net change and total change were insignificant due to weak human activity intensity in most of the study area, and the LUCC was dominated by quasi-balanced two-way transitions from 1990 to 2010. The insignificant overall amount of LUCC appears to have resulted from offsetting of rapid increases in population, economic growth, and the im- plementation of a program to return farmland to woodland and grassland in 2000. This program converted more farmland into woodland and grassland from 2000 to 2010 than from 1990 to 2000, but reclamation of woodland and grassland for use as farmland continued from 2000 to 2010, and is a cause for concern to the local government.

关键词： land use and land cover change remote sensing forest restoration Ningwu County Loess Plateau

Winter and summer monsoonal evolution in Gonghe Basin, northeastern Qinghai-Tibetan Plateau since the Last Glacial Maximum

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Research in Cold and Arid Regions 2013年第3期5卷 282-292页

作者： Bing Liu HeLing Jin Zhong sun zhizhu su CaiXia Zhang Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences School of History and Culture Shanxi University

Geochemical and grain size analysis on the DQ （Dongqi） profile from Gonghe Basin, northeastern Qinghai-Tibetan Plateau, indi- cates that regional climate has experienced several cold-dry and warm-wet cycles since the last glacial maximum （LGM）. The cold and dry climate dominated the region before 15.82 cal. ka B.E due to stronger winter monsoon and weaker summer monsoon, but the climate was relatively cold and wetter prior to 21 cal. ka B.E. In 15.824.5 cal. ka B.E, summer monsoon strength in- creased and winter monsoon tended to be weaker, implying an obvious warm climate. Specifically, the relatively cold and dry condition appeared in 14.7-13.7 cal. ka B.E and 12.14.5 cal. ka B.R, respectively, while relatively warm and wet in 13.~12.1 cal. ka B.E. The winter and summer monsoonal strength presents frequent fluctuations in the Holocene and relatively warm and wet conditions emerged in 9.5~.0 cal. ka B.E due to stronger summer monsoon. From 7.0 to 5.1 cal. ka B.E, the cycle of cold-dry and warm-wet climate corresponds to frequent fluctuations of winter and summer monsoons. The climate becomes warm and wet in 5.1 2.7 cal. ka B.E, accompanying increased summer monsoon, but it tends to be cold and dry since 2.7 cal. ka B.R due to en- hanced winter monsoonal strength. In addition, the evolution of regional winter and summer monsoons is coincident with warm and cold records from the polar ice core. In other words, climatic change in the Gonghe Basin can be considered as a regional re- sponse to global climate change.

关键词： last glacial maximum period Gonghe Basin aeolian deposits winter and summer monsoonal evolution

The formation age and evolution of Kumtagh Desert

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Journal of Arid Land 2011年第2期3卷 114-122页

作者： JinNian TANG zhizhu su Feng DING ShuJuan ZHU YouHao E XinWei ZHAI ZhiYu Yl HuJun LIU JinChun ZHANGI FaMing LI Minqin National Studies Station for Desert Steppe Ecosystem Minqin 733300 China State key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating Gansu Desert Control ResearchInstitute Lanzhou 730070 China School of History and Culture Shanxi University Taiyuan 030006 China Lanzhou University Lanzhou 730000 China

The ancient aeolian sand has been regarded as an indicator for the formation and evolution of a desert in the past.Kumtagh Desert is located at the northern fringe of Qinghai-Tibet Plateau.The first integrated scientific investigation to the desert was carried out during the period of 2004-2006.Kumtagh Desert is an ideal natural model for studying the formation and evolution of the desert because the Quaternary strata containing ancient aeolian sands are widely distributed.The integrated field investigation and studies on sedimentary,chronology and palynology of typical profiles named suosuo gully,Xiaoquan gully and gravel body with ancient aeolian sand layers showed that Kumtagh Desert was probably formed as early as 2,097.7±314.7 ka BP.During the period of 386.9±58.0 ka BP to 285.9±42.9 ka BP,the desert largely expanded and formed its modern distribution pattern.The desert was originally developed in the southwest,subsequently,expanded to the north and northeast.The sedimentary facies of suosuo gully profile revealed that the desert experienced at least 19 cycles of advance and inverse processes of desertification with an average period of 110 ka in the Quaternary.The neotectonic movements played an important role in the formation,development and geomorphology of the desert.On one hand,the movements caused the formation of intermontane fault basin,which was further developed towards the closed drought basin,and caused the formation of natural environment.On the other hand,under the control of surrounding faults,the unique broom-shaped desert landscape was formed,and the gullies and sand ridges in this region experienced an abrupt directional change from north by west to north by east at the location of 39°45＇-39°55＇N.The unique landscape of gravel body that occurred widely in the northern desert was formed after 285.9±42.9 ka BP.The results in this paper provide the scientific basis for studying the formation age and evolutionary process under the dry climate and environment in the northwestern China,and the up

关键词： Kumtagh Desert formation age evolution ancient aeolian sand

Ultra-high-Q free-space coupling to microtoroid resonators

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Light(Science & Applications) 2024年第4期13卷 682-695页

作者： Sartanee suebka Euan McLeod Judith su Wyant College of Optical Sciences University of ArizonaTucsonAZUSA Department of Biomedical Engineering University of ArizonaTucsonAZUSA

Whispering gallery mode(WGM)microtoroid resonators are one of the most sensitive biochemical sensors in existence,capable of detecting single molecules.The main barrier for translating these devices out of the laboratory is that light is evanescently coupled into these devices though a tapered optical fiber.This hinders translation of these devices as the taper is fragile,suffers from mechanical vibration,and requires precise positioning.Here,we eliminate the need for an optical fiber by coupling light into and out from a toroid via free-space coupling and monitoring the scattered resonant light.A single long working distance objective lens combined with a digital micromirror device(DMD)was used for light injection,scattered light collection,and imaging.We obtain Q-factors as high as 1:6´108 with this approach.Electromagnetically induced transparency(EIT)-like and Fano resonances were observed in a single cavity due to indirect coupling in free space.This enables improved sensing sensitivity.The large effective coupling area(~10μm in diameter for numerical aperture=0.14)removes the need for precise positioning.Sensing performance was verified by combining the system with the frequency locked whispering evanescent resonator(FLOWER)approach to perform temperature sensing experiments.A thermal nonlinear optical effect was examined by tracking the resonance through FLOWER while adjusting the input power.We believe that this work will be a foundation for expanding the implementation of WGM microtoroid resonators to real-world applications.

关键词： coupling scattered precise