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Assessing Reclamation Levels of Coastal Saline Lands with Integrated Stepwise Discriminant Analysis and laboratory Hyperspectral Data

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Pedosphere 2006年第2期16卷 154-160页

作者： SHI Zhou CHENG Jie-Liang HUANG Ming-Xiang ZHOU Lian-Qing institute of Agricultural remote sensing and Information System Zhejiang University Hangzhou 310029 （China）. state key laboratory of remote sensing science Institute of Remote Sensing Application Chinese Academy of Sciences Beijing 100101 （China）

At different times over the past 30 years in Zhejiang Province, china, the coastal tidelands have been successively enclosed and reclaimed for agricultural land use. The purpose of this work was to evaluate whether laboratory hyperspectral data might be used to estimate the physicochemical characteristics of these reclaimed saline soils. A coastal region of Shangyu City (Zhejiang Province), which was grouped into four subzones according to reclamation history, was used as the study area, and soil samples were collected in each subzone. Physicochemical analyses showed that the soils were characterized by high electrical conductivity and sand content with low organic matter; the longer the saline lands had been reclaimed, the lower were the electrical conductivity and sand content and the higher the organic matter content. These changing trends of soil chemical and physical properties were found in laboratory reflectance spectra of soil samples and their first-order derivative curves. Stepwise discriminant analysis (SDA) identified six salient spectral bands at 488, 530, 670, 880, 1400, and 1900 nm. Using derived discriminant functions for saline lands with different historical years of reclamation, classification revealed an overall accuracy from a self-test of 86.6% and from cross-validation of 89.3%. Therefore, as opposed to time-consuming field investigations, this study suggested that remotely sensed hyperspectral data could serve as a promising measure to assess the reclamation levels of coastal saline lands.

关键词： hyperspectra reclamation remote sensing saline soil SDA

Biomass estimation and uncertainty analysis based on CBERS-02 CCD camera data and field measurement

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science china(Technological sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2, GAO Yanhua1,3, CHENG Yu1,3, WEI Zheng1,3, XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. state key laboratory of remote sensing science, institute of remote sensing applications, chinese academy of sciences, beijing 100101, china 2. Geography and Environment College, Jiangxi normal university, Nanchang 330027, china 3. Graduate university of chinese academy of sciences, beijing 100039, china 4. beijing Research institute of Uranium Geology, beijing 100875, china 5. institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china state key laboratory of remote sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Geography and Environment College Jiangxi Normal University Nanchang 330027 China Graduate university Chinese Academy of Sciences Beijing 100039 China beijing Research institute of Uranium Geology Beijing 100875 China institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02 satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02 CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02 CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

Study of coastal water zone ecosystem health in Zhejiang Province based on remote sensing data and GIS

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Acta Oceanologica Sinica 2010年第5期29卷 27-34页

作者： CHEN Zhenghua PAN Delu BAI Yan School of the Environment Gangxi University Nanning 530004 China state Environmental Protection key laboratory of Satellite remote sensing Ministry of Environmental Protection Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China state key laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

The coastal ecosystem health assessment is a field of increasing *** this paper,a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made,mainly based on remote sensing data and GIS *** spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique ***,human activities,hydrology and ecosystem problems in the study area were discussed and ***,from 4 aspects of human stress,physical,chemical and biological responses to anthropogenic activities and natural stress,several indicators such as water transparency（Secchi Disk Depth,SDD）,suspended substance concentration,dissolved inorganic nitrogen,active phosphate,chlorophyll,harmful algae bloom,as well as distribution of sewage,sea lanes and port were ***,the Analytic Hierarchical Process was used for indicator weight calculation,and the ecosystem health criteria were established according to the integrative analysis of national water quality criteria,similar coastal ecosystem health research in other places or data inherent *** results indicated that from 2005 to 2007 the coastal water ecosystem health value in Zhejiang Province was unhealthy and needs ecological restoration by human intervention.

关键词： coastal water zone ecosystem health indicator remote sensing GIS

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 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 2School of Geography,beijing normal university,beijing 100875,china 3Office for Disease Control and Emergency Response,chinese Center for Disease Control and Prevention,beijing 102206,china 4Graduate university of chinese academy of sciences,beijing 100049,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 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%-20%,20%-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

The application of hyperspectral remote sensing to coast environment investigation

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Acta Oceanologica Sinica 2009年第2期28卷 1-13页

作者： ZHANG Liang ZHANG Bin CHEN Zhengchao ZHENG Lanfen TONG Qingxi state key laboratory of remote sensing science Institute of Remote Sensing Applications Chinese Academy of Science Beijing 100101 China Naval institute of Hydrographic Surveying and Charting Tianjin 300061 China Center for Earth Observation and Digital Earth Chinese Academy of Science Beijing 100190 China

Requirements for monitoring the coastal zone environment are first summarized. Then the appli- cation of hyperspectral remote sensing to coast environment investigation is introduced, such as the classification of coast beaches and bottom matter, target recognition, mine detection, oil spill identification and ocean color remote sensing. Finally, what is needed to follow on in application of hyperspectral remote sensing to coast environment is recommended.

关键词： hyperspectral remote sensing coastal zone ocean color remote sensing

Absolute radiometric calibration of CBERS-02 IRMSS thermal band

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science china(Technological sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2,3, GU Xingfa1,3,4, YU Tao1,3, ZHANG Yuxiang5, CHEN Liangfu1,3, LI Xiaoying1,2,3, LI Xiaowen1,3 & HE Liming6 1. 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 100101, china 2. Graduate university of chinese academy of sciences, beijing 100039, china 3. The Center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. National Satellite Meteorological Center, beijing 100081, china 6. state Environmental Protection Administration, beijing 100029, china state key laboratory of remote sensing science Beijing Normal University Chinese Academy of Sciences Beijing 100101 China Graduate university Chinese Academy of Sciences Beijing 100039 China Center for National Spaceborne Demonstration Beijing 100101 China National Satellite Meteorological Center Beijing 100081 China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France state Environmental Protection Administration Beijing 100029 China

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2004 are carried out in this research. When making onboard blackbody calibration of CBERS-02 IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02 IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2004 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02 IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2sr?1μm?1) and 44.92 (offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

Quantitative estimation of the shrub canopy LAI from atmosphere-corrected HJ-1 CCD data in Mu Us Sandland

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science china Earth sciences 2010年第S1期53卷 26-33页

作者： CHEN Wei1,2,CAO ChunXiang1,HE QiSheng1,2,GUO HuaDong3,ZHANG Hao1,2,LI RenQiang4,ZHENG Sheng1,2,XU Min1,2,GAO MengXu1,2,ZHAO Jian1,2,LI Sha1,NI XiLiang1,2,JIA HuiCong1,JI Wei1,TIAN Rong1,2,LIU Cheng1,2,ZHAO YuXing5 & LI JingLu6 1 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 100101,china 2 Graduate university of chinese academy of sciences,beijing 100049,china 3 Center for Earth Observation and Digital Earth,chinese academy of sciences,beijing 100190,china 4 china key laboratory of Ecological Network Observation and Modeling,institute of Geographical sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 5 Ordos Forestry Sand Control science institute,Dongsheng 017000,china 6 Inner Mongolia Biomass Thermoelectricity Limited Company,Wushen 017300,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 university of chinese academy of sciences Beijing China Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing China china key laboratory of Ecological Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Ordos Forestry Sand Control science institute Dongsheng China Inner Mongolia Biomass Thermoelectricity Limited Company Wushen China

The leaf area index(LAI) is an important ecological parameter that characterizes the interface between vegetation canopy and the *** addition,it is used by most process-oriented ecosystem *** paper investigates the potential of HJ-1 CCD data combined with linear spectral unmixing and an inverted geometric-optical model for the retrieval of the shrub LAI in Wushen Banner of Inner Mongolia in the Mu Us ***(Moderate Resolution Atmospheric Radiance and Transmittance Model) was used for atmospheric *** was extracted using the threshold of the normalized difference vegetation index,with which water bodies and farmland were separated,in combination with a vegetation map of the People's Republic of china(1:1000000).Using the geometric-optical model,we derive the per-pixel reflectance as a simple linear combination of two components,namely sunlit background and *** fraction of sunlit background is related to the shrub *** the support of HJ-1 CCD data,we employ linear spectral unmixing to obtain the fraction of sunlit background in an atmospherically corrected HJ *** addition,we use the measured shrub canopy structural parameters for shrub communities to invert the geometric-optical model and retrieve the pixel-based shrub *** total,18 sample plots collected in Wushen Banner of Inner Mongolia are used for *** results of the shrub LAI show good agreement with R2 of 0.817 and a root-mean-squared error of 0.173.

关键词： shrub leaf area index inversion HJ-1 data geometric-optical model MODTRAN Mu Us Sandland

Radiometric cross-calibration of the CBERS-02 CCD camera with the TERRA MODIS

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science china(Technological sciences) 2005年第S2期48卷 44-60页

作者： LI Xiaoying1,2,3, GU Xingfa1,3,4, MIN Xiangjun5, YU Tao1,3, FU Qiaoyan5, ZHANG Yong1,2,3 & LI Xiaowen1,3 1. 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 100101, china 2. Graduate university of chinese academy of sciences, beijing 100039, china 3. The Center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. china Center for Resource Satellite Data and Application, beijing 100830, china state key laboratory of remote sensing science Beijing Normal University Chinese Academy of Sciences Beijing 100101 China Graduate university Chinese Academy of Sciences Beijing 100039 China Center for National Spaceborne Demonstration Beijing 100101 China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France china Center for Resource Satellite Data and Application Beijing 100830 China

For the application of the CCD camera, the most important payload on CBERS-02, the key is to provide long-term stable radiometric calibration coefficients. Although the vicarious calibration had been proved successful, it had its limitations such as test site requirement and unsuitable for historical data. Cross-calibration is one of the alternative methods, but it needs synchro surface spectrum to achieve spectral band matching factors. Our effort is to probe the influences on these factors. Simulations with a lot of surface spectrum showed that the factors changed with the viewing geometry, atmospheric condition and surface targets. However, simulating with the same viewing geometry and atmospheric condition, the spectral band matching factors of the same or similar surface targets’ spectrum acquired from different dates and different places would like to be consistent to each other within 1%―5%. Thus, the synchro measurement data can be substituted by the same or similar target from other source. Based on this method, using the MODIS as the reference, the cross-calibration was performed for CCD camera. The research demonstrated that the traditional method with single calibration site was inappropriate for CCD camera, since the offsets for its four spectral bands were not zeros. With four calibration sites, these offsets were obtained. And the camera was detected to degrade with dates based on four times of cross-calibrations.

关键词： CBERS-02 CCD camera cross-calibration the spectral band matching factors.

Aerosol retrieval over land by exploiting the synergy of TERRA and AQUA MODIS DATA

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science china Earth sciences 2006年第6期49卷 641-649页

作者： TANG Jiakui1, XUE Yong1,2, YU Tong3, GUAN Yanning1, CAI Guoyin1 & HU Yincui1 1. 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 100101, china 2. Department of Computing, London Metropolitan university, 166-220 Holloway Road, London N7 8DB, UK 3. beijing Environmental Monitor Center, beijing 100044, 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 Department of Computing London Metropolitan University London UK beijing Environmental Monitor Center Beijing China

Aerosol retrieval over land from satellite remotely sensed data remains internationally a difficult task. By using MODIS data, the Dark Dense Vegetation (DDV) algorithm aerosol distribution and properties retrieval over land has shown excellent competence. However, this algorithm is re-stricted to lower surface reflectance such as water bodies and dense vegetation, which limits its actual application, and is unable to be used for high reflective surface such as over urban areas. In this paper, we introduce a new aerosol retrieval model by exploiting the Synergy of TERRA and AQUA MODIS data (SYNTAM), which can be used for various ground surfaces, including for high reflective surface. Preliminary validations have been carried out by comparing with AERONET measured data, which shows good accuracy and promising potential. Further research work is undergoing.

关键词： aerosol retrieval, aerosol optical thickness, MODIS, TERRA, AQUA.