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Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

Science china Earth Sciences 2010年第5期53卷 721-730页

作者： WANG DongWei1,2.3, WANG JinDi1,2.& LIANG ShunLin4 1 State key laboratory of {2. {2. Science, Jointly Sponsored by beijing Normal University and Institute of {2. {2. Applications, CAS, beijing 100875, china 2.school of geography, beijing key laboratory of environmental remote sensing and digital city, beijing Normal University, beijing 100875, china 3 Haihe River Water Conservancy Commission, Tianjin 300170, china 4 Department of geography, University of Maryland, College Park, MD 2.742. USA 1. State key laboratory of {2. {2. Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing 100875 China2. School of Geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing 100875 China3. Haihe River Water Conservancy Commission Tianjin 300170 China4. Department of Geography University of Maryland College Park MD 20742 USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The key approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of {2., this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS

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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1 & LIU Changming1, 2.1. school of environmental Sciences, {2. Normal University, beijing 100875, china 2. Institute of Geographic Science and Natural Resources Research, {2. 100101, china beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982.1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982.to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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3D building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG Xue 1,WENG JingNong 1,2.XIA YuBin 2.WU Lun 3 & SUI ZhengWei 3 1 College of Software,Beihang University,beijing 100191,china 2.College of Computer,Beihang University,beijing 100191,china 3 Institute of remote sensing and GIS,Peking University,beijing 100871,china Beihang Univ Coll Software Beijing 100191 Peoples R China Beihang Univ Coll Comp Beijing 100191 Peoples R China Peking Univ Inst Remote Sensing & GIS Beijing 100871 Peoples R China

The real world is a three-dimensional(3D)space requiring that 3D geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3D building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3D geospatial data on the web.3D city building model with its related information is an important part in the construction of a {2. city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3D building model,an abstract of a 3D building model based on structure details is studied,and a novel representation approach named 3D transparent building hierarchical model is presented in this *** approach fully uses both the existing 3D modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3D *** addition,based on the characteristics of the 3D building model data,a service-oriented architecture and Web service technologies for 3D city building models are *** aim of the approach is that 3D city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3D modeling 3D transparent building hierarchical models china Star web services

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Chinese HJ-1A/B satellites and data characteristics

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中国科学：地球科学英文版 2010年第S1期53卷 51-57页

作者： WANG Qiao1,WU ChuanQing1,LI Qing1 & LI JunSheng2.1 Satellite Environment Center,Ministry of environmental Protection,beijing 10002.,{2. 2.Center for Earth Observation and digital Earth,Chinese Academy of Sciences,beijing 100190,{2. 1. Satellite Environment Center Ministry of Environmental Protection Beijing 100029 China2. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China

From the viewpoint of environmental remote-{2. applications,this article explains the overall technical characteristics of the Chinese HJ-1A and HJ-1B *** also investigates the spectral characteristics and potential applications of charge-coupled devices,and the infrared and hyperspectral data obtained by the *** of applications,such as the remote-{2. monitoring of algal bloom in Taihu Lake,straw burning in southern china,and aerosol optical depth in the area around Bohai sea are *** examples illustrate the application characteristics of the HJ-1A and HJ-1B satellite data.

关键词： HJ-1A/B application remote sensing characteristics

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remote sensing application system for water environments developed for Environment Satellite 1

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中国科学：地球科学英文版 2010年第S1期53卷 45-50页

作者： WU ChuanQing1,WANG Qiao1,ZHANG YongJun1,LI JunSheng2.WU YuanFeng2.ZHU Li1 & YAO YanJuan1 1 Satellite Environment Center,Ministry of environmental Protection,beijing 10002.,{2. 2.Center for Earth Observation and digital Earth,Chinese Academy of Sciences,beijing 100190,{2. 1. Satellite Environment Center Ministry of Environmental Protection Beijing 100029 China2. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China

remote sensing data collected by the Environment Satellite I are characterized by high temporal resolution,high spectral resolution and mid-high spatial *** designed the remote sensing Application System for Water Environments(RSASWE) to create an integrated platform for remote sensing data processing,parameter information extraction and thematic mapping using both remote sensing and GIS *** system provides support for regional water environmental monitoring,and prediction and warning of water *** to process and apply data collected by Environment Satellite I,this system has automated procedures including clipping,observation geometry computation,radiometric calibration,6S atmospheric correction and water quality parameter *** consists of six subsystems:remote sensing image processing,basic parameter inversion,water environment remote sensing thematic outputs,application outputs,automated water environment outputs and a non-point source pollution monitoring *** present RSASWE plays an important role in operations at the Satellite Environment Center.

关键词： water environment remote sensing Application System Environment Satellite 1

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Object-oriented land cover classification using HJ-1 remote sensing imagery

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Science china Earth Sciences 2010年第S1期53卷 34-44页

作者： SUN ZhongPing1,SHEN WenMing1,WEI Bin1,LIU XiaoMan1,SU Wei2.ZHANG Chao2.& YANG JianYu2.1 Satellite Environment Center,Ministry of environmental Protection,beijing 100094,{2. 2.College of Information and Electrical Engineering,{2. Agricultural University,beijing 100083,{2. 1. Satellite Environment Center Ministry of Environmental Protection Beijing 100094 China2. College of Information and Electrical Engineering China Agricultural University Beijing 100083 China

The object-oriented information extraction technique was used to improve classification accuracy,and addressed the problem that HJ-1 CCD remote sensing images have only four spectral bands with moderate spatial *** used two {2. techniques:the selection of optimum image segmentation scale and the development of an appropriate object-oriented information extraction *** the principle of minimizing merge cost of merging neighboring pixels/objects,we used spatial autocorrelation index Moran's I and the variance index to select the optimum segmentation *** Nearest Neighborhood(NN) classifier based on sampling and a knowledge-based fuzzy classifier were used in the object-oriented information extraction *** this classification step,feature optimization was used to improve information extraction accuracy using reduced data *** two techniques were applied to land cover information extraction for Shanghai {2. using a HJ-1 CCD *** indicate that the information extraction accuracy of the object-oriented method was much higher than that of the pixel-based method.

关键词： HJ-1 remote sensing imagery object-oriented optimum scale of image segmentation Nearest Neighborhood(NN) classification fuzzy classification

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Soil Moisture and Oilseed Rape Yields as Affected by Configuration of Ridge-furrow Tillage in the Semiarid Region of china

Soil Moisture and Oilseed Rape Yields as Affected by Configu...

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2.07中国科协年会

作者： Liu Muxing~1 Wang Jingai~(2.4) Liu Lianyou~(2.3) Yan Ping~(2.3) 1.College of city and Environment,Huazhong Normal University,Wuhan 430079,china 2.{2. {2. of environmental Change and Natural Disaster of Ministry of Education,beijing Normal University,beijing 100875,china 3.College of Resources Science & Technology,beijing Normal University,beijing 100875,china 4.College of geography and remote sensing Sciences,beijing Normal University,beijing 100875,china

Ridge-furrow tillage is a kind of conservation tillage widely used for soil and water conservation in agriculture,with crop planted in ridge or *** previous researches mostly focus on the effects of ridge-furrow tillage with crop planted in ridges on crop growth and soil water content,Influence of ridge-forrow tillage with crop planted in furrows are not well documented,despite it is helpful to crop growth in arid and semiarid *** purpose of this study was evaluating the effect of ridge-furrow tillage with different surface configurations and crop planted in furrow,on the efficiency for rainwater harvesting and crop production,to determine the optimal surface configuration of ridge-furrow *** parameters of ridge heights (H) and ridge-furrow ratios (R,ratio between H and furrow width,W) were defined to determine the configuration of ridge-furrow *** field experiments,seasonal dynamic variation of volumetric soil water content, aboveground biomass and yields of oilseed rape (Brassica napus L.) were *** treatments included four kinds of ridge-furrow tillage with oilseed rape planted in furrow and one kind of conventional field tillage (CT) for *** results indicate that relative to CT,ridge-furrow tillage increased volumetric soil water content of the plow layer (0-30 cm) by 4.2.-12.1%,decreased its fluctuation in the growing season of oilseed *** the soil profile under ridge-furrow tillage,soil layer with the highest soil water content appeared in the depth of 0-30 cm,which helped oilseed rape absorb water by *** aboveground biomass,pods per plant and 1000-seed weigh under ridge-furrow tillage were larger than that under *** field comparison of oilseed rape yields under four forrow planting practices with 15,2. cm H and 1/6,1/12.1/2. R,we found the practice with 2. cm H and 1/2. R increased the efficiency of water harvesting,the growth and yield of the oilseed rape more ***,we recommend furr

关键词： ridge-furrow tillage furrow planting volumetric soil water content aboveground biomass theoretical yield rainfed agriculture

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Ecological Instream Flow Requirements Calculation of Pihe River by Montana Methodology in Sichuan Basin,china

Ecological Instream Flow Requirements Calculation of Pihe Ri...

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2.07中国科协年会

作者： W.Ouyang~(1,2. F.H.Hao~1 H.Chen~1 X.Wang~1 S.T.Yang~3 1.school of Environment,State key {2. of Water Environment Simulation,2.{2. Normal University 2.International Institute for Geo-Information Science and Earth Observation(ITC),Netherlands 3.State key {2. of remote sensing Science,{2. key {2. for remote sensing of Environment and digital Cities,school of geography,{2. Normal University

With the rapid economic developments in china,the future water resource developments should be sustainable and that a component of the natural flow of rivers should be reserved to ensure diverse ecological *** last 15 years,ecological instream flow requirements(EIFR)research of river was one of the main and hot fields for eco-hydrology *** this paper,we summarized the research advance of eco-hydrology and also,the conception of the EIFR was also followed and *** ecological instream flow has three main functions:maintain the water ecological environments,dilute pollutants and *** coordinate with the water resource allocation,we evaluated EIFR of Pihe River section in every 12.month of three typical years (1968,1986 and 1987).Pihe River is one of the main waterr sources for the cities in Sichuan Basin and locates in the lower beach of famous Doujiang *** Montana methodology was widely applied in water requirements estimate and proved *** on natural characters of Pihe River,minimum and optimum water requirement of aquatic habitat for the river maintenance were *** water requirement of Pihe River was computed too,which is related with the width of water surface,the river length and evaporation depth. Considering the water quality goal,diluting pollutant water requirement was taken into *** the EIFR of the river of 12.month were ultimateS,*** them,that was 2..64m/s and the minimum eco-environmental water requirement of the river was 2..84m/s.

关键词： Eco-environmental water requirements Water resource allocation Water quality goal Pollutant dilute water requirement

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Mapping forest fire risk zones with spatial data and principal component analysis

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Science china(Technological Sciences) 2006年第z1期49卷 140-149页

作者： XU Dong, Guofan Shao, DAI Limin, HAO Zhanqing, TANG Lei & WANG Hui Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, china Graduate University of Chinese Academy of Sciences, beijing 100039, china Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Department of Management, Shenyang Institute of Aeronautical Engineering, Shenyang 110034, china Department of city Development, Jinan University, Jinan 2.0002. china 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China2. Graduate University of Chinese Academy of Sciences Beijing 100039 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Department of Management Shenyang Institute of Aeronautical Engineering Shenyang 110034 China5. Department of City Development Jinan University Jinan 250002 China

By integrating forest inventory data with remotely sensed data, new data layers for factors that affect forest fire potentials were generated for Baihe Forestry Bureau in Jilin Province of china. The principle component analysis was used to sort out the relationships between forest fire potentials and {2. factors. The classifications of these factors were performed with GIS, generating three maps: a fuel-based fire risk map, a topography-based fire risk map, and an anthropogenic-factor fire risk map. These three maps were then synthesized to generate the final fire risk map. The linear regression method was used to analyze the relationship between an area-weighted value of forest fire risks and the frequency of historical forest fires at each forest farm. The results showed that the most important factor contributing to forest fire ignition was topography, followed by anthropogenic factors.

关键词： wildfire risk, regression analysis, geographic information system, remote sensing, Baihe Forestry Bureau.

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Spatial distribution analysis of landslides triggered by 2.08.5.12.Wenchuan Earthquake,china

Spatial distribution analysis of landslides triggered by 200...

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中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Shengwen Qi~(a,b,*),Qiang Xu~b,Hengxing Lan~c,Bing Zhang~d,Jianyou Liu~(a,1) a key Lab.of Engineering Geomechanics,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing,{2.,P.O.Box 982.,Chaoyang area,beijing,10002.,{2. b State key Lab.of Geo-hazard Prevention and Geo-environment Protection,Chengdu University of Technology,Chengdu,610059,{2. c State key laboratory of Resources and environmental System,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,beijing,100101,{2. d Centre for Earth Observation and {12. Earth,Chinese Academy of Sciences,beijing,100190,{2.

The 2.08.5.12.Wenchuan Earthquake(seismic magnitude M 7.9 according to the USGS)triggered a great number of landslides.A spatial database of landslides is built by interpreting the remote sensing(RS)data which covers 11 counties severely damaged by the earthquake with area of about 31,686.12.*** geological settings of the study area are detailed mapped including geologic structure and *** {2. elevation model(DEM)of the study area with resolution of 30 m×30 m is presented to address the topographic *** between the occurrence of landslides with geological settings i.e. active faults(the coseismic surface ruptures),geological unit,slope gradient,slope elevation as well as slope aspect are analyzed using spatial modeling in GIS with the aids of field *** can be concluded that the distance to the causative faults and slope gradient are much more important than other factors. Landslides are clustered distributed along the causative faults of F2.and F3,and landslides incidence are dramatically decreasing with the increasing of the distance to the causative *** landslides incidence has an obvious increase near the active faults *** concentration(LC,landslides/km)has an obvious exponent increase with slope ***,LC has no obvious relationship with geological unit and slope elevation;the difference of LC value in each geological unit(each slope elevation category)maybe have been the result affected by slope gradient for each geological unit(each slope elevation category)and distance of each geological unit(each slope elevation category)to causative fault *** map reflects the incidence of landslides in some degree,and LC increases dramatically with Intensity increasing, almost all landslides occurred in the region aboveⅥdegree. Statistics result also indicates that in the near field of causative faults,landslides tend to have the initial sliding direction similar to the movement

关键词： 2.08.5.12.Wenchuan Earthquake Slope Landslide Spatial analysis

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