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

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 {3. Sensing science,jointly sponsored by the institute of {3. Sensing applications of chinese academy of sciences and {13. normal university,{13. 100101,china 2 Graduate university of chinese academy of sciences,{13. 100049,china 3.Center for Earth Observation and Digital Earth,chinese academy of sciences,{13. 100190,china 4 china key laboratory of Ecological Network Observation and Modeling,institute of Geographical sciences and Natural Resources Research,chinese academy of sciences,{13. 100101,china 5 Ordos Forestry Sand Control science institute,Dongsheng 017000,china 6 Inner Mongolia Biomass Thermoelectricity Limited Company,Wushen 0173.0,china state key laboratory of {3. 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 {3. 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

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Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

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science china Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3. MA Haizhou2, LI Zhen4, TAN Hongbing2 & WANG Xianyan1 1. state key laboratory of Loess and Quaternary Geology, {3. of Earth Environment, chinese academy of sciences, Xi’an 710075 china 2. Qinghai {3. of Salt Lakes, chinese academy of sciences. Xining 810008, china 3. {3. of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 4. Department of Geography, Qinghai normal university, Xining 810008, china state key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China Department of Geography Qinghai Normal University Xining China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (103. samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3. T2, T1 were formed at 14, 11.3. 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3. 1.2 and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 43. m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

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An improved line-of-sight method for visibility analysis in 3. complex landscapes

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science china(Information sciences) 2010年第11期53卷 2185-2194页

作者： LIU Liu1, ZHANG LiQiang1, MA JingTao2, ZHANG Liang3. ZHANG XingMing1, XIAO ZhiQiang1 & YANG Ling1 1state key laboratory of {3. Sensing science, jointly sponsored by beijing normal university and the institute of {3. Sensing applications of {13. academy of sciences, beijing 100875, china 2PTV America, Inc. 1145 Broadway Plaza Ste 605, Tacoma, WA 98407, USA 3.chool of Geomatics and Urban Information, beijing university of Civil Engineering and Architecture, beijing 100044, china state key laboratory of {3. Sensing science Jointly Sponsored by Beijing Normal University and the Institute of Remote Sensing Applications of Chinese Academy of Sciences PTV America Inc.

This paper presents an efficient method for implementing visibility analysis on complex landscapes based on an improved LOS (line of sight) algorithm. The method determines the viewshed by analyzing the geometric relationship between the target points and viewpoint. It differentiates the visibility of the target points by the elevation information. Eventually the visual results related to the given viewpoint are rendered on three-dimensional landscapes. The visibility of some target points is computed by comparing their elevations with the viewpoint's height, thus is able to enhance the efficiency of the visibility analysis. This method can not only be applied in the visibility analysis of forest scenes, but also used in the analysis of the urban environment. Experiments show that the proposed method results in high efficiency and precision.

关键词： line of sight visibility analysis complex landscapes visual permeability

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Designing regional pattern for ecosystem restoration:A case study

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science china(Technological sciences) 2006年第z1期49卷 86-97页

作者： LI Guoqiang , MA Keming, FU Bojie & LIU Shiling state key Lab of Systems Ecology, Research Center for Eco-environmental sciences, {3. academy of sciences, beijing 100085, china Department of Water Environment, china institute of Water Resources and Hydropower Research, beijing 10003., china School of Environmental sciences, beijing normal university, beijing 100875, china state key Lab of Systems Ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Designing regional pattern is challenging for ecosystem restoration both in theory and in practice. The present study proposed a new approach to design regional pattern for ecosystem restoration with a case in the arid valley of Upper Minjiang River, SW china. The procedures are: (1) Determine the regional pattern of main environmental factors based on the relationships between the important environmental factors and the main geographical factors generated from DEM data. (2) Overlay the maps of the main environmental factors. (3. Generate a lookup table according to the species selection rule we proposed to link the candidate restoration species to the main environmental factors.(4) Determine the regional pattern of ecosystem restoration by positioning the restoration species in the map of environmental factors according to the lookup table. The regional restoration pattern designed in this way would be applicable not only to restoring a region, but also to predicting the future landscape change.

关键词： environmental factors, GIS, restoration species, Upper Minjiang River Valley.

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Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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science china(Technological sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3. LI Xiaoying1,2,3. ZHANG Yong1,2,3. ZHAO Feng1,2,3. GU Xingfa1,3.4, ZHU Li1,2,3. WANG Pengxin5 & MIN Xiangjun6 1. state key laboratory of {3. Sensing science institute of {3. Sensing Application, CAS, Bei- jing 100101, china 2. Graduate university of chinese academy of sciences, beijing 10003., 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. College of Information and Electrical Engineering, china Agricultural university, beijing 100083. china 6. china Center for Resource Satellite Data and Application, beijing 10083., china state key laboratory of {3. Sensing science institute of remote Sensing Application CAS Beijing 100101 China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

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Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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science china Chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3. ZHAO Ying2, LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4, ZHANG Nengwei3. ZHANG Yuanfu1 & WU Jinguang1 1. The state key laboratory of Rare Earth Materials and {3., College of Chemistry and Molecular Engineering, Peking university, beijing 100871, china 2. institute of Chemistry, chinese academy of sciences, beijing 100080, china 3. Department of Surgery, Third Hospital, Peking university, beijing 100083. china 4. Department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, china Correspondence should be addressed to Wu Jinguang (email: wujg@***) The state key laboratory of Rare Earth Materials and {3. College of Chemistry and Molecular Engineering Peking University Beijing China Department of Surgery Third Hospital Peking University Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China Department of Oncology Surgery the First Hospital of Xi’an Jiaotong University Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3. normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

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Study on the changes of water cycle and its impacts in the source region of the Yellow River

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science china(Technological sciences) 2004年第z1期47卷 142-151页

作者： ZHANG Shifeng1, JIA Shaofeng1, LIU Changming1, CAO Wenbing2, HAO Fanghua3. LIU Jiuyu4 & YAN Huayun5 1. institute of Geographic sciences and Natural Resources Research, chinese {3. of sciences, beijing 100101, china 2. china university of Geosciences, beijing 100083. china 3. beijing {13. university, beijing 100875, china 4. Bureau of Hydrology of Yellow River Conservancy Commission, Zhengzhou 450003. china 5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province, Xining 810001, china institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of china in the 21st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

关键词： source region of the Yellow River, water cycle, evaporation, negative equilibrium.

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The role of different cues in the brain mechanism on visual spatial attention

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Progress in Natural science:Materials International 2006年第10期16卷 1045-1050页

作者： SONG Weiqun, LUO Yuejia, CHI Song, JI Xunming, LING Feng, ZHAO Lun, WANG Maobin and SHI Jiannong ( Department of Rehabilitation, Xuanwu Hospital, Capital university of Medical science, beijing 100053. {3. state key laboratory of Cognitive Neuroscience and Learning, beijing normal university, beijing 100875, {3. School of Psychology, Southwest university, Chongqing 400715, {3. key laboratory of Mental Health, institute of Psychology, chinese academy of sciences, beijing 100101, {3. Department of Neurology, Affiliated Hospital of Qingdao university, Medical College, Qingdao 266003. {3. Department of Neurology, Xuanwu Hospital, Capital university of Medical science, beijing 100053. {3. institute of Linguistics, Xuzhou normal university, Xuzhou 221116, {3.) Department of Rehabilitation Xuanwu Hospital Capita! University of Medical Science Beijing 100053 China state key laboratory of Cognitive Neuro{3. and Learning Beijing Norma! University Beijing 100875 China School of Psychology Southwest University Chongqing 400715 China key laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Department of Neurology Affiliated Hospital of Qingdao University Medical College Qingdao 266003 China Department of Neurology Xuanwu Hospital Capital University of Medical Science Beijing 100053 China institute of Linguistics Xuzhou Normal University Xuzhou 221116 China

The visual spatial attention mechanism in the brain was studied in 16 young subjects through the visual search paradigm of precue-target by the event-related potential (ERP) technique, with the attentive ranges cued by different scales of chinese character and region cues. The results showed that the response time for chinese character cues was much longer than that for region cues especially for small region cues. With the exterior interferences, the target stimuli recognition under region cues was much quicker than that under chinese character cues. Compared with that under region cues, targets under chinese character cues could lead to increase of the posterior P1, decrease of the N1 and increase of the P2. It should also be noted that the differences between region cues and chinese character cues were affected by the interference types. Under exterior interferences, no significant difference was found between region cues and chinese character cues; however, it was not the case under the interior interferences. Considering the difference between the exterior interferences and the interior interferences, we could conclude that with the increase of difficulty in target recognition there was obvious difference in the consumption of anterior frontal resources by target stimuli under the two kinds of cues.

关键词： visual spatial attention cue scale event-related potential (ERP) chinese character cues region cues.

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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

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Progress in Natural science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2, Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3.1. state key Laboatory for Mineral Deposits Research and Center for Marine Geochemistry Research, Department of Earth sciences, Nanjing {3., Nanjing 210093. china 2. Tarim Oilfield Company Exploration & Development Research institute, Ku’erle 841000, china 3. institute of Mineral Resources, chinese academy of Geological sciences, beijing 10003., china) state key laboratory for Mineral Deposits Research and Center for Marine Geochemistry Research Department of Earth Sciences Nanjing University Nanjing 210093 China Tarim Oilfield Company Exploration & Development Research institute Ku'' erle 841000 China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23.. The results showed that the δ3.Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4—26.3.) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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APPLICATION OF SWAT MODEL IN THE UPSTREAM WATERSHED OF THE LUOHE RIVER

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chinese Geographical science 2003年第4期13卷 334-339页

作者： ZHANG Xue-song, HAO Fang-hua, CHENG Hong-guang, LI Dao-feng (state key laboratory of Water Environment Simulation,{3. of Environmental sciences, beijing normal university,beijing 100875,P. R. china) state key laboratory of Water Environment Simulation Institute of Environmental Sciences Beijing Normal University Beijing 100875 P. R. China

In the Huanghe (Yellow) River basin,soil erosion is a serious problem,while runoff and sediment yield simulation has not been extensively studied on the basis of GIS (Geographic Information System) and distributed hydrological model. GIS-based SWAT (Soil and Water Assessment Tool) model was used to simulate runoff and sediment in the Huanghe River basin. The objective of this paper is to examine the applicability of SWAT model in a large river basin with high sediment runoff modulus,which could reach 770t/(km2·a). A two-stage "Brute Force" optimization procedure was used to calibrate the parameters with the observed monthly flow and sediment data from 1992 to 1997,and with input parameters set during the calibration process without any change the model was validated with 1998-1999’s observed data. Coefficient of examination (R2) and Nash-Suttcliffe simulation efficiency (Ens) were used to evaluate model prediction. The evaluation coefficients for simulated flow and sediment,and observed flow and sediment were all above 0.7,which shows that SWAT model could be a useful tool for water resources and soil conservation planning in the Huanghe River basin.

关键词： luohe river watershed SWAT model sediment flow

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