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THE　EARLY　FROST　CHARACTERISTICS　AND　ITS　PREVENTIVE　AND　CURATIVE　STRATEGY　FOR　FRUIT　TREES　IN　YUCHENG，SHANDONG　PROVINCE

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Natural Disaster Reduction in china 1996年第2期 85-87页

作者： Su Peixi (lanzhou institute of desert,{3. )

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关键词： EARL

LAND desertIFICATION(DEGRADATION) AND ITS CONTROL IN LOWER REACH REGION OF HEIHE RIVER

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干旱区资源与环境 1993年第Z1期7卷 63-65页

作者： Chen Longhen institute of desert research, Academia Sinica, {3., china

The lower reach of Heihe River, also known as Ejina River, was called Ruoshui Riverin ancient times. This area, although fallen into extremely arid temperate desert in the EjinaBanner, Inner Mongolia, has been a main line of communication since then and formed thefertile Ejina Oasis relying on the water source flowing from the Qilian mountains. However,in the recent years the land desertification (degradation) in this area has developed rapidly,

关键词： Heihe River Lower Reaches desertification Oasis

Temperature and precipitation trends in Minqin desert during the period of 1961-2007

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Journal of Arid Land 2011年第3期3卷 214-219页

作者： ShuJuan ZHU1,2,3.ZhaoFeng CHANG1,2,3.1 Gansu Minqin National Field Observation & research Station on Ecosystem of desertified Rangeland,Minqin 73.3.0,china 2 Key Laboratory of desertification Combating of Gansu Province,lanzhou 73.070,china 3.Gansu desert Control research institute,lanzhou 73.070,china Gansu Minqin National Field Observation and research Station on Ecosystem of desertified Rangeland Minqin 733300 China Key Laboratory of desertification Combating of Gansu Province Lanzhou 733070 China Gansu desert Control research institute Lanzhou 733070 China

This paper analyzed the data of temperature and precipitation in Minqin,typical desert area in north-west china,during the period of 1961 2007 by linear *** result indicated that the increasing rate of the mean annual temperature in Minqin was higher than that of the average of china;and the temperature in February increased by 3.01oC averagely in the past 47 *** climate in Minqin displayed an evident warming ***,there was no evidently increasing trend of precipitation in the past 47 years,and drought occurred during the whole growing season.

关键词： temperature precipitation global climate Minqin

Experimental study of surface texture and resonance mechanism of booming sand

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Science china Earth sciences 2007年第9期50卷 1351-1358页

作者： QU JianJun1, ZHANG KeCun1, SUN Bo2, JIANG ShengXiang3. DONG GuangRong1, ZU RuiPing1 & FANG HaiYan 1 Key Laboratory of desert and desertification, Cold and Arid Regions Environmental and Engineering research {3., chinese academy of sciences, lanzhou 730000, china 2 Shanghai {3. of Polar Regions, Shanghai 210000, china 3.lanzhou {3. of Chemical Physics, chinese academy of sciences, lanzhou 730000, china Key Laboratory of desert and desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shanghai institute of Polar Regions Shanghai 210000 China lanzhou institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The sound-producing mechanism of booming sand has long been a pending problem in the blown sand physics. Based on the earlier researches, the authors collected some silent sand samples from Teng- ger desert, Australian desert, Kuwait desert, beaches of Hainan Island and Japanese coast as well as the soundless booming sand samples from the Mingsha Mountain in Dunhuang to make washing ex- periments. In the meantime the chemical corrosion experiment of glass micro-spheres, surface coating experiment and SEM examination were also conducted. The experimental results show that the sound production of booming sand seems to have nothing to do with the presence of SiO2 gel on the surface of sand grains and unrelated to the surface chemical composition of sand grains but is related to the resonance cavities formed by porous (pit-like) physical structure resulting from a number of factors such as wind erosion, water erosion, chemical corrosion and SiO2 gel deposition, etc. Its resonance mechanism is similar to that of Hemholz resonance cavity. Under the action of external forces, nu- merous spherical and sand grains with smooth surface and porous surface are set in motion and rub with each other to produce extremely weak vibration sound and then become audible sound by human ears through the magnification of surface cavity resonance. However the booming sands may lose their resonance mechanism and become silent sand due to the damping action caused by the invasion of finer particles such as dust and clay into surface holes of sand grains. Therefore, clearing away fine pollutants on the quartz grain surface is an effective way to make silent sand emit audible sound.

关键词： booming sand, surface texture, quartz grain, sound-producing mechanism, Hemholz resonance cavity

Aeolian Facies Belts in the Taklimakan desert

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 317-328页

作者： Li Baosheng, Dong Guangrong, Zhang Jiasheng, Li Sen,Jin Heling, Chen Huizhong, Wen Xiangle, Wang Yao, lanzhou desert research {3., chinese academy of sciences, Lamhou, Gansuand Zhu YizhiXi’an Open Laboratory of Loess and Quaternary Geology, chinese academy of sciences, Xi’an, Gansu Fei Zhenbi lanzhou desert research {3. Chinese Academy of Sciences Lanzhou Gansu China

At least at the beginning of the last glacial epoch, the facies belts of dune sand, sandy loam and loess formed by winds had existed in the Taklimakan desert and areas south of it. There were no appreciable changes in the NE and NW wind systems and their wind fqrces that deposited dune sand, sandy loam and loess in the global cold stage since the last glacial epoch (accordingly no marked shifts of the boundaries of these aeolian facies belts took place. In the global warm stage since then, the climate in the Taklimakan desert and areas south of it became warm and dry, resulting in ablation of substantial volumes of ice and snow in their surrounding mountains and thus forming alluvial and diluvial deposits in the region. The alluvial-diluvial actions, however, failed to change the general framework of aeolian facies belts.

关键词： Taklimakan desert sandy loam belt loess belt last glacial depositional environment

Simulation of oasis breeze circulation in the arid region of the Northwestern china

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Science china Earth sciences 2004年第Z1期47卷 101-107页

作者： LU Shihua, AN Xingqin & CHEN YuchunCold and Arid Regions Environmental and Engineering research institute, chinese academy of sciences,{3., china Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences Lanzhou 730000 China

In this paper, the process of oasis-desert circulation (ODC) is simulated by MM5V3.5 model through designing an ideal oasis-desert scheme and assuming that initial atmosphere is at rest (V = 0). The findings showed that the key of forming special oasis boundary structure is the difference of energy and water between oasis and desert. The evaporation of oasis surface consumes heat energy, and the low temperature of oasis causes an oasis breeze circulation (OBC), which drives an ODC with a downdraft over the oasis and an updraft over the desert. Later, the cold, dry and stable boundary over oasis is gradually formed, on the contrary,the atmospheric boundary over desert on the edge of oasis is hot, humid and unstable and its height is about 600 hPa. The updraft over the desert forms a wet ring that acts as a vertical wall weakening the low-level moisture exchange between the oasis and desert. The downdraft of OBC increases the atmospheric stability that reduces the oasis evaporation. The low-level outflow from the oasis (into the desert) prevents the dry, hot air flowing from the desert into the *** an oasis self-preservation mechanism may be formed due to OBC. The horizontal area influenced by oasis is twice as oasis area and the vertical range is four times as oasis. The ODC is strong in the daytime and reaches the strongest at 17:00, and the influenced area is the largest at 20:00.

关键词： oasis atmospheric boundary layer numerical simulation.

Remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,china

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Science china(Technological sciences) 2010年第S1期53卷 176-183页

作者： XU Min 1,2,CAO ChunXiang 1,TONG QingXi 1,LI ZengYuan 3.ZHANG Hao 1,HE QiSheng 1,2,GAO MengXu 1,2,ZHAO Jian 1,2,ZHENG Sheng 1,2,CHEN Wei 1,2 & ZHENG LanFen 1 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the institute of Remote Sensing Applications of chinese academy of sciences and Beijing Normal University,Beijing 100101,china 2 Graduate School of the chinese academy of sciences,Beijing 100049,china 3.research institute of Forest Resources and Information Techniques,chinese academy of Forestry,Beijing 10009,china State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate School of the chinese academy of sciences Beijing China research institute of Forest Resources and Information Techniques Chinese Academy of Forestry Beijing China

The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ***-1A/B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,*** correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction *** prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than *** AGB and carbon storage were mapped using the RVI based prediction model in *** statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 16 799 200 t,which has greatly contributed to the carbon fixation in northern china.

关键词： above-ground biomass carbon storage Mu Us desert HJ-1A/B remote sensing

Variations of Snow Temperature and their Influence on Snow Cover Physical Parameters in the Western Tianshan Mountains,china

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Journal of Mountain Science 2011年第6期8卷 827-837页

作者： CHEN Xia WEI WenShou LIU MingZhe GU GuangQin Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Hebei Key Laboratory for Meteorology and Eco-environmen Shijiazhuang 050021 China HeBei Climate Center Shijiazhuang 050021 China institute of desert Meteorology China Meteorological Administration Urumqi 830011 China Tianshan Station for Snow-cover and Avalanche research Chinese Academy of Sciences Urumqi 830011 China

This article discussed about snow temperature variations and their impact on snow cover *** temperature recorders were used to sample at 10-minute intervals at the Tianshan Station for Snow-cover and Avalanche research,chinese academy of {3..10-layer snow temperature and the snow cover parameters were measured by the snow property analyzer (Snow Fork) in its Stable period,Interim period and Snow melting *** indicate that the amplitude of the diurnal fluctuation in the temperature during Snow melting period is 1.62 times greater than that during Stable *** up to the peak temperature at the snow surface lags behind the peak solar radiation by more than 2.5 hours,and lags behind the peak atmospheric temperature by more than 0.2 hours during all three *** optimal fitted function of snow temperature profile becomes more complicated from Stable period to Snow melting period.22 h temperature profiles in Stable period are the optimal fitted by cubic polynomial *** Interim period and Snow melting period,temperature profiles are optimal fitted by exponential equation between sunset and sunrise,and by Fourier function when solar radiation is *** vertical gradient in the snow temperature reaches its maximum value at the snow surface for three *** peak of this maximum value occurs during Stable period,and is 4.46 times greater than during Interim *** absolute value of temperature gradient is lower than 0.1°C cm-1 for 3. cm beneath snow *** temperature and temperature gradient in Stable period～Interim period indirectly cause increase (decrease) of snow density mainly by increasing (decreasing) *** it dramatically increases its water content to change its permittivity and snow density in Snow melting period.

关键词：温度变化天山西部物理参数雪盖中国最佳拟合函数积雪密度峰值温度

Landscape evolution and precipitation changes in the Badain Jaran desert during the last 3. 000 years

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chinese Science Bulletin 2000年第11期45卷 1042-1047页

作者： YANG Xiaopinginstitute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

On the basis of field expeditions into different parts of the Badain Jaran desert, new evidence of landscape evolution and precipitation changes during the last 3. 000 years has been found from the geomorphological, sedimentological and geochronological studies of the megadune. Different cemented surfaces of palaeo-dunes have been observed in many localities, which are representatives of relatively moister environment. The chronological data show that four periods of more humid environment occurred in the past 3. 000 years. The stabilization of dunes in a large scale and the existence of many palaeo-lakes and lacustrine terraces confirm the periodic fluctuations of climate. It implies that the intensity of westerlies and Eastasian monsoons varied in the region of Alashan, and the periods of higher precipitation took place even in the times close to the last glacial maximum.

关键词： desert palaeo-dune lake global change Badain Jaran.