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Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis

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Science China Earth sciences 2010年第4期53卷 575-590页

作者： LI MingXing1,2.MA ZhuGuo1 & DU JiWen3 1 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,chinese academy of {2.,beijing 10002.,China 2.graduate university of chinese academy of {2.,beijing 100049,China 3 Shaanxi Administration of Meteorology,Xi’an 710014,China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of {2. academy of sciences Beijing China Shaanxi Administration of Meteorology Xi’an China

The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the *** to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the *** model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic *** deeper soil layers,high soil moisture appears in the river basins and *** regional soil moisture showed a generally decreasing trend on all soil layers from 1951 to 2.04,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.

关键词： SWAT soil moisture content simulation validation trend analysis

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3, ZHANG Jin4 1. Institute of Geodesy and Geophysics, chinese academy of {2., Wuhan 430077, China 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, chinese academy of {2., Wuhan 430077, China 3. graduate School of chinese academy of {2., beijing 100049, China 4. Department of Surveying and Mapping, Taiyuan university of Technology, Taiyuan 03002., China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China graduate School of chinese {2. of sciences Beijing 100049 China Department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

Valuations on arithmetic surfaces

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Science China Mathematics 2009年第1期52卷 66-76页

作者： XU Ning Department of Mathematics, graduate School of chinese {2. of sciences, beijing 100049, China Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing China

In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ? p,G is algebraically closed. Based on this the author obtains the complete classification of valuations on arithmetic surfaces. Furthermore, for any m ? p,G n ∈ ?, let V m,n be an ∝-vector space of dimension n - m + 1, whose coordinates are indexed from m to n. We generalize the definition of ? p,G , where p is a prime and G ? V m,n is an additive subgroup containing 1. We also conclude that ? p,G is a field if m ? 0 ? n.

关键词： valuation height rank totally ordered group big field transcendental number 14J10

Sea level variations in the South China Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science China Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3 & XU HouZe 1,3 1 State Key Laboratory of Geodesy and Earth’s Dynamics,Institute of Geodesy and Geophysics,chinese academy of {2.,Wuhan 430077,China 2.graduate university of chinese academy of {2.,beijing 100049,China 3 Institute of Geophysics,Huazhong university of Science and Technology,Wuhan 430074,China State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China graduate university of {2. academy of sciences Beijing China Institute of Geophysics Huazhong University of Science and Technology Wuhan China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South China Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3 cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993-2.09,which is significantly higher than the global sea level rise rate of 3.3±0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South China Sea sea level variation

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2.& TANG XianChun2.3 1 Department of Earth sciences, Nanjing university, Nanjing 2.0093, China 2.Guangzhou Institute of Geochemistry, {2. academy of sciences, Guangzhou 510640, China 3 graduate university of chinese academy of sciences, beijing 100049, China Department of Earth sciences Nanjing University Nanjing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of {2. academy of sciences Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science China Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2.3 1. National Marine Environmental Forecasting Center, beijing 100081, China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, chinese {2. of sciences, beijing 10002., China 3. graduate university of chinese {2. of sciences, beijing 100049, China National Marine Environmental Forecasting Center Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences graduate university of {2. academy of sciences

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Quantitative analysis of soil pores under natural vegetation successions on the Loess Plateau

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Science China Earth sciences 2010年第4期53卷 617-625页

作者： ZHAO ShiWei1,ZHAO YongGang1,2.& WU JinShui3 1 State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest Agriculture & Forestry university,Yangling 712.00,China 2.graduate university of chinese academy of sciences,beijing 100049,China 3 Institute of Subtropical Agriculture,chinese academy of sciences,Changsha 41012.,China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling China graduate university of {2. academy of sciences Beijing China Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha China

Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess *** study is to quantitatively analyze soil pore parameters,measured with Computed Tomography(CT) at 15-57 mm depths under five different vegetation succession stages using a concept of substituting "space" for "time" in the Ziwuling Forest Region of the Loess *** results showed that the soil pore parameters,such as pore number,porosity,circularity,and fractal dimension,increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage,indicating that natural vegetation recovery could remarkably improve soil pore *** the vegetation succession,this positive effect will be strengthened gradually,which means that the soil pore parameters may appear to be best at the climax community *** organic matter content increased linearly with the soil pore parameters(P<0.001).Increased organic matter accumulation was one of the major reasons for the changes in soil pore characteristics in natural vegetation succession.

关键词： Computed Tomography Loess Plateau natural vegetation succession soil pore soil organic matter

Research on applying physical chaos generator to spacecraft information security

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Science China(Technological sciences) 2009年第5期52卷 1463-1470页

作者： ZHAO HePing State Key Laboratory of Information Security,graduate university of {2. academy of sciences,beijing 100049,China China academy of Space Technology,beijing 100094,China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences China academy of Space Technology

The effectiveness of a short-length message extension method based on physical chaos generator was analyzed and the entropy of the extended message was calculated in this *** analysis demon-strated that with the mentioned method the entropy of short-length messages,which are repeatedly used in spacecraft data systems,is obviously increased,and the security of transmission is enhanced as *** paper also presented an improvement of the protocol for secret key agreement presented by *** and *** of depending on characteristics of communication channel,this method takes advantage of the random data produced by physical chaos generator to preset the initial parameters of the procedure on both sides of communication,so that the procedure and quantity of cipher key can be precisely *** method can be used to cipher key management of se-cure communication between long life-span spacecraft and ground system.

关键词： physical chaos generator spacecraft information security message extension cipher key management

Estimating forest aboveground biomass using HJ-1 Satellite CCD and ICESat GLAS waveform data

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Science China Earth sciences 2010年第S1期53卷 16-25页

作者： GUO ZhiFeng1,CHI Hong1,2.& SUN GuoQing1,3 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of chinese academy of {2. and beijing Normal university,Institute of Remote Sensing Applications,chinese academy of {2.,beijing 100101,China 2.9} university of chinese academy of {2.,beijing 100049,China 3Department of Geography university of Maryland,College Park,MD 2.742.USA 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 Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China graduate university of {2. academy of sciences Beijing China Department of Geography university of Maryland College Park USA

The ecosystem in northeastern China and the Russian Far East is a hotspot of scientific research into the global carbon *** aboveground biomass(AGB) is an important component in the land surface carbon *** this study,using forest inventory data and forest distribution data,the AGB was estimated for forest in Daxinganlin in northeastern China by combining charge-coupled device(CCD) data from the Small Satellite for Disaster and Environment Monitoring and Forecast(HJ-1) and Geoscience Laser Altimeter System(GLAS) waveform data from the Ice,Cloud and land Elevation Satellite(ICESat).The forest AGB prediction models were separately developed for different forest types in the research area at GLAS footprint level from GLAS waveform parameters and field survey plot biomass in the Changqing(CQ) Forest Center,which was calculated from forest inventory *** resulted statistical regression models have a R2.0.68 for conifer and R2.0.71 for broadleaf *** models were used to estimate biomass for all GLAS footprints of forest located in the study *** GLAS footprint biomass coupled with various spectral reflectivity parameters and vegetation indices derived from HJ-1 satellite CCD data were used in multiple regression analyses to establish biomass prediction models(R2.0.55 and R2.0.52.for needle and broadleaf respectively).Then the models were used to produce a forest AGB map for the whole study area using the HJ-1 *** data obtained from forest inventory data of the Zhuanglin(ZL) Forest Center were used as independent field measurements to validate the AGB estimated from HJ-1 CCD data(R2.0.71).About 80% of biomass samples had an error less than 2. t ha-1,and the mean error of all validation samples is 5.74 t *** pixel-level biomass map was then stratified into different biomass levels to illustrate the AGB spatial distribution pattern in this *** was found that HJ-1 wide-swath data and GLAS waveform data can be combined to estim

关键词： Disaster and Environment Monitoring and Forecast Satellite ICESat GLAS waveform boreal forest forest aboveground biomass multiple linear regression