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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

Science china(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui institute of Applied Ecology, chinese academy of sciences, Shenyang 110016,{2. School of Forestry, Northeast Forestry University, Harbin 150040,{2. state key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085,{2. Graduate University of chinese academy of sciences, Beijing 100039,{2. institute of Applied Ecology Chinese Academy of Sciences School of Forestry Northeast Forestry University state key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2., much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote {2. data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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Spatial prediction and analysis of Himalayan marmot plague natural epidemic foci in china based on HJ-1 satellite data

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Science china Earth sciences 2010年第S1期53卷 8-15页

作者： GAO MengXu1,4,LI XiaoWen1,2.CAO ChunXiang1,ZHANG Hao1,LI Qun3,ZHOU Hang3 HE QiSheng1,4,XU Min1,4,ZHAO Jian1,4,ZHENG Sheng1,4 & CHEN Wei1,4 1state key {2. 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.chool of Geography,Beijing Normal University,Beijing 100875,china 3Office for Disease Control and Emergency Response,chinese Center for Disease Control and Prevention,Beijing 102.06,china 4Graduate University of chinese academy of sciences,Beijing 100049,china state key {2. 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 University of chinese academy of sciences Beijing China School of Geography Beijing Normal University Beijing China Office for Disease Control and Emergency Response Chinese Center for Disease Control and Prevention Beijing China

Plague,caused by the gram-negative bacterium Yersinia pestis,is a serious and rapidly progressing illness in humans that can be fatal if not treated *** Qinghai-Tibet Plateau is the largest area of natural Himalayan marmot(Marmota himalayana) plague foci in china and covers more than 630000 *** County in Gansu Province is a part of this natural focus of plague and was chosen as a study *** study used an ecological niche modeling(ENM) approach to predict the potential distribution of the Himalayan *** and Disaster Monitor Satellite(HJ-1) data was used to investigate environment factors that affect plague host animal *** animal point data from active surveillance was combined with environmental variables from the HJ-1 satellite and other databases,and the models of the potential distribution of Himalayan marmot were produced with the Genetic Algorithm for Rule-Set Production(GARP).The probability of marmot presence was divided into 0-5%,5%-2.%,2.%-40%,40%-80%,and 80%-100% *** with 80%-100% probability exhibited the greatest potential for the presence of Himalayan *** to the predicted potential distribution of Himalayan marmot in the study area,active surveillance of plague hosts and plague control and prevention could be more efficient.

关键词： Himalayan marmot plague spatial prediction GARP HJ-1 satellite

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Architecture and application of integrated spatial information service platform for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1, XIAO Jie2.1. College of Mining, Taiyuan University of Technology, Taiyuan 03002., china 2. institute of Geodesy and Geophysics,{2., Wuhan 430077, china College of Mining Taiyuan University of Technology Taiyuan 030024 China institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote {2. data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine

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A Spectral Index for Estimating Soil Salinity in the Yellow River Delta Region of china Using EO-1 Hyperion Data

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Pedosphere 2010年第3期20卷 378-388页

作者： WENG Yong-Ling GONG Peng ZHU Zhi-Liang Department of Surveying and Mapping Engineering College of Transportation Southeast University Nanjing 210096(China) state key {2. of remote sensing Science Institute of Remote Sensing Applications of the Chinese Academy ofSciences and Beijing Normal University Beijing 100101 (China) Department of Environment Science Policy and Management University of California Berkeley CA 94720 (USA) EROS Data Center U.S. Geological Survey Sioux Falls SD 57198 (USA)

Soil salinization is one of the most common land degradation processes. In this study, spectral measurements of saline soil samples collected from the Yellow River Delta region of china were conducted in laboratory and hyperspectral data were acquired from an EO-1 Hyperion sensor to quantitatively map soil salinity in the region. A soil salinity spectral index (SSI) was constructed from continuum-removed reflectance (CR-reflectance) at 2.52.and 2.03 nm, to analyze the spectral absorption features of the salt-affected soils. There existed a strong correlation (r = 0.91) between the SSI and soil salt content (SSC). Then, a model for estimation of SSC with SSI was established using univariate regression and validation of the model yielded a root mean square error (RMSE) of 0.986 and an R2.of 0.873. The model was applied to a Hyperion reflectance image on a pixel-by-pixel basis and the resulting quantitative salinity map was validated successfully with RMSE = 1.92. and R2.= 0.62.. These suggested that the satellite hyperspectral data had the potential for predicting SSC in a large area.

关键词： hyperspectral reflectance soil salt content spectral absorption features

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Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW china

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Journal of Mountain Science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai Department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China state key {2. of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China institute of remote {2. applications Chinese Academy of Sciences Beijing 100101 China Centre for Hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern china. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.

关键词： Vertical distribution of land cover Anthropogenic activity Vegetation activity Environmental variability china

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In flight MTF monitoring and compensation for CCD camera on CBERS-02

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Science china(Technological sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2.3, LI Xiaoying1,2.4, MIN Xiangjun5, YU Tao1,2. SUN Jijuan5, ZENG Yong1,2.4, XU Hua1,2.& GUO Ding2.6 1. state key {2. 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. The Center for National Spaceborne Demonstration, Beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. Graduate University of chinese academy of sciences, Beijing 100039, china 5. china Center for Resource Satellite Data and Application, Beijing 100830, china 6. University of Electronic Science and Technology of china, Chengdu 610054, china state key {2. of remote sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University The Center for National Spaceborne Demonstration

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5 for 45° directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 45° axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

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Using soil surface gray level to determine surface soil water content

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Science china Earth sciences 2010年第10期53卷 1527-1532页

作者： ZHU YuanJun1,2.WANG YunQiang1,2.& SHAO MingAn1,2.1 state key {2. of Soil Erosion and Dryland Farming on Loess Plateau,institute of Soil and Water Conservation,Northwest A & F University,Yangling 712.00,china 2.institute of Soil and Water Conservation,chinese academy of sciences & Ministry of Water Resources,Yangling 712.00,china state key {2. of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water Conservation Northwest A & F University Yangling China institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources Yangling China

How to determine surface soil water content(SWC) quickly and accurately is fundamental in studying eco-hydrological processes and their *** we use laboratory experiments to determine surface SWC using soil surface gray level(SGL) values.A negatively exponential relationship exists between SGL and SWC,i.e.,SGL increases with the decrease of *** can be estimated based on initial SGL value(surface gray level when SWC=0),SWC,and a surface roughness coefficient characterized by mean soil particle *** variation range of SGL was larger than that of SWC,indicating that changes in SWC were enhanced in SGL,and that SGL would thus be sensitive to changes in soil *** the 95% confidence level,SWC can be determined by using the relationship between SWC and SGL established by the *** determination of SWC has a high precision when SWC was between dry and saturated.

关键词： Loess Plateau soil water remote sensing surface roughness

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Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science china(Technological sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2. ZHANG Taihua1, LI Weihuo3 & WEI Bingchen3 1. state key {2. of Nonlinear Mechanics (LNM), institute of Mechanics, chinese academy of Sci- ences, Beijing 100080, china 2. College of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 300074, china 3. National Microgravity {2., institute of Mechanics, chinese academy of sciences, Beijing 100080, china state key {2. of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China sychology.lu.se

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

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Focal plane wave-front sensing algorithm for high-contrast imaging

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Science china(Physics,Mechanics & Astronomy) 2009年第8期52卷 1284-1288页

作者： DOU JiangPei1,2.3,REN DeQing1,2.4,ZHU YongTian1,2.& ZHANG Xi1,2.3 1 National Astronomical Observatories/Nanjing institute of Astronomical Optics & Technology,chinese {2. of sciences,Nanjing 2.0042.china 2.key laboratory of Astronomical Optics & Technology,Nanjing institute of Astronomical Optics & Technology,chinese {2. of sciences,Nanjing 2.0042.china 3 Graduate University of{{12.,Beijing 100049,china 4 Physics & Astronomy Department,California state University Northridge,18111 Nordhoff Street,Northridge,California 91330-82.8,USA National Astronomical Observatories/Nanjing institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China key laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China Graduate University of chinese academy of sciences Beijing China Physics & Astronomy Department California State University Northridge Northridge USA

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star.A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error of an optical *** derive an algorithm for the wave-front measurement directly from 3 focal plane *** 3 images are achieved through a deformable mirror to provide specific phases for the optics *** introduce an extra amplitude modulation on one deformable mirror configuration to create an uncorrelated wave-front,which is a critical procedure for wave-front *** simulation shows that the reconstructed wave-front is consistent with the original wave-front theoretically,which indicates that such an algorithm is a promising technique for the wave-front measurement for the high-contrast imaging.

关键词： high-contrast imaging multi-image algorithm speckle nulling technique wave-front sensing

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Spectral response of rice(Oryza sativa L.) leaves to Fe^(2.) stress

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Science china(Life sciences) 2009年第8期52卷 747-753页

作者： CHI GuangYu1,2.CHEN Xin1,SHI Yi1 & LIU XinHui3 1 key laboratory of Terrestrial Ecological Process,{2. of Applied Ecology,chinese academy of sciences,Shenyang 110016,china 2.Graduate School of chinese academy of sciences,Beijing 100049,china 3 state key Joint laboratory of Environmental Simulation and Pollution Control,School of Environment,Beijing Normal University,Beijing 100875,china key laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Graduate School of chinese academy of sciences Beijing China state key Joint {2. of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing China

In the management of lake eutrophication,the regulation effect of Fe is considered,in addition to the controlling nitrogen-and phosphorus *** on the "Fe hypothesis",this paper tentatively applied plant spectral response to the remote sensing early-warning mechanism of lake eutrophication.A {2. water culture experiment with rice(Oryza sativa L.) was conducted to study Fe uptake by plants and the chlorophyll concentration and visible-near infrared spectrum of vegetable leaves as well as their interrelations under Fe2. *** spectral indices,i.e.,A1(integral value of the changes of spectral reflectivity in the range 460―670 nm under Fe2. stress),A2.integral value of the changes of spectral reflectivity in the range of 760―1000 nm under Fe2. stress) and S(blue-shift range of red edge curve under Fe2. stress),were used to establish quantitative models about the relationships between the rice leaf spectrum and Fe2. *** the increase of Fe2. in a culture solution,the Fe content in rice plants increased,while the chlorophyll concentration in vegetative leaves *** spectral reflectivity of vegetable leaves increased in the visible light band but decreased in the near infrared band,and the blue-shift range of the red edge curve *** indices A1,A2.and S all had significant correlations with the Fe content in rice leaves,the correlation coefficient being respectively 0.951(P 2.> 0.96) and predict the Fe level in rice leaves.

关键词： rice(Oryza sativa L.) spectrum Fe2. lake eutrophication

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