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Regional Yield Estimation of Summer Maize Based on Assimilation of remotely Sensed LAI into EPIC Model

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Regional Yield Estimation of Summer Maize Based on Assimilat...

2010 Second IITA International Conference on Geoscience and remote sensing (IITA-GRS 2010)

作者： Jianqiang REN1,2,Fushui YU1,2,Zhongxin CHEN1,2,,Jun QIN3.1 Key laboratory of Resources remote-sensing & {3. Agriculture,Ministry of Agriculture,beijing 100081,china 2 Institute of Agricultural Resources & Regional Planning,Chinese Academy of Agricultural Sciences,beijing 100081,china 3.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,beijing 100085,china

In order to acquire more accurate crop yield information,the global optimization algorithm SCE-UA was used to integrate leaf area index derived from remote sensing with crop growth model EPIC to simulate regional summer maize yield and field management information in Huanghuaihai Plain in china. The results showed that the mean relative error of estimated summer maize yield was 4.3.% and RMSE was 0.4.t/ha. Compared with the actual field observation data,the mean relative error of simulated sowing date,plant density and net nitrogen fertilization application rate was 1.85%,-7.78% and -10.60% respectively. These above simulated results could meet need of accuracy of crop growth simulation and yield estimation at regional scale. It was proved that integrating remotely sensed LAI with EPIC model based on SCE-UA for simulating regional summer maize yield and field management information was feasible and reliable.

关键词： data assimilation global optimization algorithm Crop growth model EPIC yield estimation remote sensing LAI

EXTRACTION OF BIOCHEMICAL COMPONENTS IN WINTER WHEAT BY CANOPY HYPERSPECTRUM

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EXTRACTION OF BIOCHEMICAL COMPONENTS IN WINTER WHEAT BY CANO...

Progress of Information Technology in Agriculture

作者： Huang Wenjiang Wang Jihua Liu Liangyun Zhao Chunjiang Huang Muyi Wang JindiNational Engineering Research Center for Information Technology in Agriculture beijing Post Code:100089 chinaResearch Center for remote {3. and GIS beijing Normal University beijing Post Code:100875 china

＜正＞ Winter wheat canopy spectrum is affected by wheat canopy （leaf area index, leaf biochemical components, leaf angle distribution,canopy shadows, et al.）, soil, weeds, environment and their interactions. So the uncertainties for crop canopy spectral information become a fatal problem for the canopy biochemical and biophysical variables extraction. Recent studies have demonstrated the application of spectral indices from hyperspectral data for crop biochemical and biophysical variables. These indices are the compositive response to variations of several vegetation and environmental properties. Canopy chlorophyll content, an indicator of photosynthesis activity, which is related the nitrogen concentration in green vegetation and serves as a measure of the crop response to nitrogen application. The combination of NDVI and PRI can reduce the effect of LAI and soil background. The index （CCII） was proved to be sensitive to chlorophyll concentration and very resistant to the variations. This paper introduced the application of the ratio TCARI/OSAVI to make accurate predictions of winter wheat chlorophyll content under different varieties, and the application of SIPI for canopy biochemical indicators inversion by minimizing foliar inner structure effect. It indicated that the canopy chlorophyll content and nitrogen concentration could be evaluated by some new combination vegetation indices.

关键词： winter wheat canopy spectrum uncertainties information extraction

Ceometric calibration of high-resolution remote sensing sensors

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Ceometric calibration of high-resolution remote sensing sens...

5th Asian Symposium on Geographic Information System from Computer Science & Engineering View

作者： LIANG Hong-you~(1,2,3. GU Xing-fa~1 TAO Yu~1 QIAO Chao-fei~4.(1.Graduate University of Chinese Academy of Sciences,beijing 10003.,P.R.china 2.State Key {4. of {3. sensing Science,Institute of {3. sensing Applications,CAS,beijing 100101,P.R.china 3.Henan Polytechnic University,Jiaozuo 4.4.03.P.R.china 4.Development and Research Center for Surveying and Mapping State Bureau of Surveying and Mapping,beijing 10004.,P.R.china)

＜正＞This paper introduces the applications of high-resolution remote sensing imagery and the necessity of geometric calibration for remote sensing sensors considering assurance of the geometric accuracy of remote sensing *** the paper analyzes the general methodology of geometric *** the DMC sensor geometric calibration as an exam- ple,the paper discusses the whole calibration ***,it gave some concluding remarks on geometric calibration of high-resolution remote sensing sensors.

关键词： digital camera geometric calibration geometric correction remote sensing

基于GIS技术的浅层地下水硝酸盐氮浓度场数值仿真

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系统仿真学报 2004年第6期16卷 1254-1256页

作者：宫辉力尹连旺赵文吉张松梅首都师范大学资源环境与GIS北京市重点实验室三维信息获取与应用教育部重点实验室北京100037 中国科学院遥感应用研究所北京师范大学资源科学研究所

地理信息系统(GIS)技术与数值模拟技术相结合,揭示地下水硝酸盐氮浓度场的时空变化特征。采用准三维数值仿真技术,建立地下水水流模型、溶质运移模型和地下水运动方程组成的地下水水质模型。先解地下水水流模型,得到地下水渗流场水位函... 详细信息

地理信息系统(GIS)技术与数值模拟技术相结合,揭示地下水硝酸盐氮浓度场的时空变化特征。采用准三维数值仿真技术,建立地下水水流模型、溶质运移模型和地下水运动方程组成的地下水水质模型。先解地下水水流模型,得到地下水渗流场水位函数H(x,y,t);再解地下水运动方程得到各单元的地下水实际流速;最后解溶质运移模型,求出计算区内任一点的硝酸盐氮浓度。数值模拟与空间分析结果表明,研究区地下水水质系统状态比较稳定,硝酸盐氮浓度场的时空分布变化较小。

关键词：硝酸盐氮浓度场有限元数值仿真

Using hyperspectral indices to estimate foliar chlorophyll a concentrations of winter wheat under yellow rust stress

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Using hyperspectral indices to estimate foliar chlorophyll a...

The First International Conference on Computers and Computing Technologies in Agriculture

作者： LI JING~(1,2) JIANG JINBAO~1 CHEN YUNHAO~(1,2,*) WANG YUANYUAN~1 SU WEI~3.HUANG WENJIANG~4.1 College of Resources Science and Technology beijing Normal University No.19 Xinjiekouwai Street beijing 100875,china 2 State Key {3. of Earth Surface Processes and Resource Ecology beijing Normal University No.19 Xinjiekouwai Street beijing 100875,china 3.College of Information & Electrical Engineering china Agricultural University beijing 100083.china 4.National Engineering Research Center for Information Technology in Agriculture beijing 100089,china

The canopy hyperspectral reflectance of winter wheat infected with yellow rust at different levels of severity were measured by an ASD FieldSpec Pro FR spectrometer in the field and the concentrations of chlorophyll a(Chl a) in the leaves corresponding to the spectra were determined by biochemical methods in the *** analyses were made between Chl a concentrations and canopy hyperspectral data of diseased wheat. Results show that foliar Chl a concentrations are strongly correlated with canopy spectrum in the visible region and the first-order derivative spectrum in blue edge,green edge,and red *** and nonlinear models for estimating Chl a concentrations of the diseased wheat were built based on several spectral *** indicate that SDr/SDg,in which SDr and SDg are the sums of the first derivative within red and green edges,outperformed the other indices in predicting Chl a *** relative estimation errors for Chl a for 12 unseen samples are 17.5%.It is concluded that derivative spectra in red edge and green edge have strong prediction power for foliar Chl a concentrations of diseased winter *** hyperspectral remote sensing data to monitor crop disease and nutrition status is very promising.

关键词： chlorophyllα estimation models hyperspectral wheat yellow rust stress

digital earth, Virtual Reality and urban seismic disaster simulation

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Journal of Geographical Sciences 2000年第2期10卷 119-128页

作者： HE Jian-bang, HU Zhi-yong, YE Ze-tian, LI Hui-guo, WANG Jin-feng (State Key laboratory of Resources & environment Information Systems, Chinese Academy of Sciences, beijing 100101,{3.)

US Vice President Al Gore's vision of digital Earth applies us with prospects for brand-new ways of solving problems the earth is facing such as seismic disaster. ms paper first briefly introduces the concept of digital Earth. Then in the context of digital Earth. the Origin, concept and application of Virtual Reality technology are reviewed. After that we present in detail our preliminary case study--CVR-USD (Computer Virtual Reality for Urban Seismic Disaster Simulation) System which aims to simulate and manage seismic disaster through integrating RS, GIS and VR technologies. For this system, we've built USD subsystem, developed SMVR software to implement CVR. and also developed a Spatial Dare Analysis Package to handle spatial data related to earthquake disaster.

关键词： digital Earth, Virtual Reality seismic disaster simulation remote sensing, GIS

Spatial pattern of land cover change in china's semiarid environment

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Journal of Arid Land 2009年第1期1卷 16-25页

作者： BaoLin LI1 and QiMing ZHOU2 1 State Key laboratory of environment and Resources Information System, Institute of Geographical Sciences and Resources Research, Chinese Academy of Sciences, beijing 100101,{3. 2 Department of Geography, Hong Kong Baptist University, Kowloon Tong, Hong Kong,{3. Hong Kong Baptist Univ Dept Geog Kowloon Tong Hong Kong Peoples R China Chinese Acad Sci State Key Lab Environm & Resources Informat Syst Inst Geog Sci & Resources Res Beijing 100101 Peoples R China

This study seeks a routine to quantify spatial pattern of land cover changes in semiarid environment of china based on post-classification comparison method. The method consists of three major steps: (1) the image classification and unification of classified results based on two-level land cover classification themes, (2) the establishment of land cover change classes based on an unification land cover classification theme, (3. the reclassification and mapping of land cover change classes with three overall classes including no-change, gain and loss based on the unification land cover class. This method was applied to detect the spatial pattern of land cover changes in Yinchuan Plain, one of famous irrigation agricultural zones of the Yellow River, china. The results showed the land cover had undergone a remarkable change from 1991 to 2002 in the study area (the changed area was over 3.%). Rapid increase of cropland (12.5%), built-up area (13..4.) and rapid decrease of bare ground (51.7%) were alarming. The spatial pattern of land cover changes showed clear regional difference in the study area and was clearly related to human activities or natural factors. Thus, it obtained a better understanding of the human impact on the fragile ecosystem of china’s semiarid environment.

关键词： change detection spatial pattern land cover semiarid zone of china remote sensing human activities

remote sensing Monitoring In the Three Gorges Reservoir Area

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Remote Sensing Monitoring In the Three Gorges Reservoir Area

2011 International Symposium on Water Resource and environmental Protection(ISWREP 2011)

作者： Bingfang Wu Lei Zhang Chao Yuan Kai Yin Liang Zhu Qiang Wang In stitute of remote sensing A pplications CAS beijing {3.

The Three Gorges Project is a back bone water resource project along the Yangtze River in china. The project has gained prominence at home and abroad not only in the comprehensive benefits, but also in the complexity and sensitivity of ecological and environmental impacts concerned. To investigate the impacts chronically, remote {3. technique was used to monitor the environmental changes and present a whole picture in the reservoir area with 5784. km2 . This paper summarizes the contents and outcomes of remote {3. monitoring, such as, land use and cover change, vegetation coverage, soil erosion, urban expansion in the area since the project was launched in 1992, and also the vegetation recovery in down-zone area when water level was raised. The corresponding ecological and environmental protection efforts in regional scale are showed.

关键词： engineering ecology environment land cover Land use

中国北方13.土地利用景观格局变化分析(19891999)

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水土保持学报 2005年第5期19卷 143-146页

作者：李月臣宫鹏陈晋刘春霞何春阳环境演变与自然灾害教育部重点实验室北京师范大学资源学院北京100875 遥感科学国家重点实验室中国科学院遥感应用研究北京100101 重庆师范大学地理科学学院重庆400047

以北方13.为研究区,对该区1989～1999年的宏观土地利用景观格局变化进行了分析.结果表明:决定该区景观格局的主体要素类型为草地、难利用地和林地,其次为耕地.1989～1999年期间,区内景观异质性程度在逐渐提高, 土地利用向着多样化和均... 详细信息

以北方13.为研究区,对该区1989～1999年的宏观土地利用景观格局变化进行了分析.结果表明:决定该区景观格局的主体要素类型为草地、难利用地和林地,其次为耕地.1989～1999年期间,区内景观异质性程度在逐渐提高, 土地利用向着多样化和均匀化方向发展.景观空间格局变化特征是:耕地、林地和城镇用地破碎度最大;林地、草地和水域受到人类活动的严重干扰,斑块空间分布不断分散和破碎化,分离度和破碎度指标增加.草地的破碎度增加最为显著,严重影响该区农牧业的正常生产.景观要素之间的转化关系主要表现为林、草地和耕地之间的相互转化,以及草地退化为难利用地.表征了该区生态建设实践和生态破坏活动的相互作用以及草地的严重退化趋势,说明北方13.存在较为严重生态环境问题,急需解决.

关键词：景观格局变化土地利用北方13.