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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 laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China institute of remote sensing 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

Using remote sensing to research beijing wetlands dynamics

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science china(Technological sciences) 2006年第Z2期49卷 97-107页

作者： ZHAO Wenji, GONG Zhaoning, GONG Huili, LI Xiaojuan, ZHANG Songmei & LI Jing key Lab of Resource Environment and GIS of beijing, Capital normal university, beijing 100037, china Northeast institute of Geography and Agroecology, chinese academy of sciences, Changchun 130012, china College of Resources science and Technology, beijing normal university, beijing 100875, china Capital normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital normal Univ GIS Beijing Beijing 100037 Peoples R China chinese Acad Sci NE Inst Geog & Agroecol Changchun 130012 Peoples R China beijing normal Univ Coll Resources Sci & Technol Beijing 100875 Peoples R China

In beijing, where wetlands are important to municipal freshwater conservation and biodiversity retention, three different types of wetlands were identified: riverside wetlands, wetlands surrounding lakes and reservoirs, and wetlands in municipal *** sensing technology was applied in combination with field investigations to monitor and analyze the changes in these wetlands, and a combination of fusion technologies,Landsat TM/ETM+ and IKONOS imaging, was used to investigate and map them. This study indicates that not only have wetland areas been reduced by half, but also their ecological environments have been degraded because of rapid economic development and population increase. Suggestions based on this research are made to reconstruct the ecological environment of the wetlands and return them to their previous state.

关键词： beijing, wetland resource, remote sensing technology, ecological environment, dynamics.

Regularizing kernel-based BRDF model inversion method for ill-posed land surface parameter retrieval using smoothness constraint

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Regularizing kernel-based BRDF model inversion method for il...

中国科学院地质与地球物理研究所2008学术年会

作者： Yanfei Wang,Changchun Yang,and Xiaowen Li 1 institute of Geology and Geophysics,chinese academy of sciences, beijing,china. 2 state key laboratory of remote sensing science and Research Center for remote sensing and GIS,beijing normal university,beijing,china.

[1]In this paper,we consider the problem how to solve the kernel-based bidirectional reflectance distribution function(BRDF) models for the retrieval of land surface albedos. The above problem is an ill-posed inverse *** will employ a new regularization technique to alleviate the *** Tikhonov regularization has been discussed for BRDF model inversion,however,much study has to be done before applying it in practice(Wang et al,2007).In this paper,we thoroughly investigate this method,and propose a discrepancy method for a posteriori choice of the regularization parameter and several options for choosing the regularizing *** proposed method can alleviate difficulties in numerical computation when the discrete kernel is badly conditioned and the number of observations is *** the proposed method can always find a set of suitable BRDF coefficients for poorly sampled *** proposed method is an improvement of the traditional least squares error algorithm in AMBRALS(Algorithm for MODIS(Moderate Resolution Imaging Spectroradiometer) Bidirectional Reflectance Anisotropies of the Land Surface),see Strahler et al.(1999),and is comparable to the regularized singular value decomposition method developed by Wang et al.(2007).Hence the proposed method can be considered as a supplemental algorithm for the robust estimation of the land surface BRDF/*** performance is given in this paper for the widely used field-based 18 data sets among the 73 data sets(see Li et al.,2001) and for the satellite data.

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Study on Developing Mechanism of Rubber-tea-chicken Agro-forestry Model in Tropical Area of china

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Study on Developing Mechanism of Rubber-tea-chicken Agro-for...

第三世界生态高峰会

作者： Meng Qingyan~(1 2) Wang Zhaoqian~3 1 Stale key laboratory of remote sensing science,jointly sponsored by the institute of Remeote sensing applications of chinese academy of sciences and beijing normal university beijing 100101,china:2 Center for Spaceborne remote sensing Demonstration.National Space Administration,beijing,100101,china:3 Agro-Ecology Research institute,Zhejiang university,Hangzhou 310029,china

Developing mechanism of rubber-tea-chicken eco-agricultural model—a typical tropical agro-forestry in Wenchang,Hainan province was studied with *** technology progressing model,stability indicator,as well as harmonizing *** correlation coefficient and producing dominance *** rational mechanism could be mainly induced as:technique promoting function, leverage function of dominance item(livestock husbandry),stability of model structure and harmony of its components,the model pillar product's meeting market need and government's supporting and drawing of favor *** study was aimed at finding out both the rational and the limiting factors in the development of the model and, fnrthermore,putting forward approaches of optimizing the model according to the local situation.

关键词： Mechanism Agro-forestry System Eco-agricultural Model Rubber-tea-chicken

Retrieval of the aerosol particle size distribution function by incorporating a priori information

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Retrieval of the aerosol particle size distribution function...

中国科学院地质与地球物理研究所2007学术年会

作者： Yanfei Wang~(a,b,*),Shufang Fan~c,Xue Feng~d a institute of Geology and Geophysics,chinese academy of sciences,P.O.Box 9825,beijing 100029,PR china b 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,PR china c Department of Mathematics,Liaocheng university,Shandong 252059,PR china d School of Geography,beijing normal university,beijing 100875,PR china

The determination of the aerosol particle size distribution function using the particle spectrum extinction equation is an ill-posed integral equation of the first *** overcome the ill-posedness,regularization techniques such as Phillips-Twomey ’s regulanzation, Tikhonov’s smooth regularization as well as some iterative methods were ***,most of the literature focuses on improving the solvability of the problem without introducing some useful a priori information,which are essential to ill-posed inverse problems,since it is known that,we are often faced with limited/insufficient observations in remote ***,we restudy this *** first formulate the problem in l space and solve a nonnegative constrained problem to obtain a useful a priori solution,then we use this solution to reformulate the problem in l space and solve a regularized *** results are based on the remotely sensed data by Sun-photometer CE 318 for Poyang lake region of Jiangxi Province and are performed to show the efficiency and feasibility of the proposed algorithms.

关键词： Aerosol particle size distribution Inversion Regularization A priori l~1 and l~2 norm Damped Gauss-Newton iteration

Eco-Environmental Vulnerability Evaluation in the Yellow River Basin,china

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Pedosphere 2008年第2期18卷 171-182页

作者： WANG Si-Yuan LIU Jing-Shi YANG Cun-Jian institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 （China） institute of Electronics Chinese Academy of Sciences Beijing 100080 （China） Centre of RS and GIS applications Sichuan Normal University Chengdu 610066 （China）

Using remote sensing(RS)data and geographical information system(GIS),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,*** objective of this study was to improve our understanding of eco-environmental changes so that a strategy of sustainable land use could be *** environmental numerical model was developed using spatial principal component analysis(SPCA)*** model contains twelve factors that include variables of land use,soil erosion,topography,climate,and *** this model,synthetic eco- environmental vulnerability index(SEVI)was computed for 1990 and 2000 for the Yellow River *** SEVI was classified into six levels,potential,slight,light,medium,heavy,and very heavy,following the natural breaks classification. The eco-environmental vulnerability distribution and its changes over the ten years from 1990 to 2000 were analyzed and the driving factors of eco-environmental changes were *** results show that the eco-environmental vulnerability in the study area was at medium level,and the eco-environmental quality had been gradually improved on the ***,the eco-environmental quality had become worse over the ten years in some *** the study area,population growth,vegetation degradation,and governmental policies for eco-environmental protection were found to be the major factors that caused the eco-environmental changes over the ten years.

关键词： eco-environmental vulnerability geographic information system (GIS) remote sensing (RS) spatial principal component analysis Yellow River Basin

Characteristics of landscape information Tupu of the Yellow River swings and its subdeltas during 1855―2000

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science china Earth sciences 2007年第10期50卷 1566-1577页

作者： YE QingHua1,3?, CHEN ShenLiang2, HUANG Chong4, XUE YunChuan5, TIAN GuoLiang3, CHEN ShuPeng3,4, SHI YaNan4, LIU QingSheng4 & LIU GaoHuan4 1 institute of Tibetan Plateau Research (ITPR), chinese academy of sciences (CAS), beijing 100085, china 2 state key laboratory of Estuarine and Coastal Research, East china normal university, Shanghai 200062, china 3 state key laboratory of remote sensing science, institute of remote sensing applications (IRSA), CAS, beijing 100101, china 4 institute of Geographic sciences and Natural Resources Research, CAS, beijing 100101, china 5 Qingdao Meteorological Bureau, Qingdao 266003, china institute of Tibetan Plateau Research (ITPR) Chinese Academy of Sciences (CAS) Beijing 100085 China state key laboratory of remote sensing science Institute of Remote Sensing Applications (IRSA) CAS Beijing 100101 China state key laboratory of Estuarine and Coastal Research East China Normal University Shanghai 200062 China institute of Geographic sciences and Natural Resources Research CAS Beijing 100101 China Qingdao Meteorological Bureau Qingdao 266003 China state key laboratory of remote sensing science Institute of Remote Sensing Applications (IRSA) CAS Beijing 100101 China state key laboratory of remote sensing science Institute of Remote Sensing Applications (IRSA) CAS Beijing 100101 China institute of Geographic sciences and Natural Resources Research CAS Beijing 100101 China

Based on the theories and methods of cartography on spatial pattern and temporal evolution in Geo-information Tupu (Carto-methodology in Geo-information, CMGI) and the quantitative measurements of pattern and process in landscape ecology, the methodology of landscape information Tupu in studying the swing process of the Yellow River (YR) over the Yellow River Delta (YRD) during 1855― 2000 has been demonstrated. The main content includes: (1) methodology of landscape information Tupu; (2) evolution process Tupu of YR rump channels; (3) evolution process Tupu of the 7 pieces of subdeltas in YRD during 1855―2000; (4) landscape information Tupu of the modern YRD and the current YRD; (5) landscape information Tupu of YR rump channels on the 7 pieces of subdeltas during 1855―2000; and (6) corridor-matrix landscape information Tupu by YR swings. The methodology of landscape information Tupu here is still primary but we hope that it could provide a new tool for exploring an integrated research on spatiotemporal approaches for landscape "pattern and process".

关键词： Geo-information Tupu, landscape information Tupu, spatiotemporal analysis, the Yellow River (YR), the Yellow River Delta (YRD), corridor-matrix landscape

Satellite SAR interferometric observations of displacements associated with urban subsidence in Suzhou, Eastern china

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Progress in Natural science:Materials International 2002年第10期 80-82+84页

作者： WANG Chao, ZHANG Hong, LIU Zhi, CHENG Suozhong and LU Guonian(1. LARSIS, institute of remote sensing applications, chinese academy of sciences, beijing 100101, china 2. Department of Geography, Nanjing normal university, Nanjing 210097, china) LARSIS Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101China Department of Geography Nanjing Normal University Nanjing 210097 China

SAR interferometry (InSAR) has a high potential for surface displacement mapping in the range from millimeter to meter. In this paper the potential of ERS-1/2 SAR interferometry for mapping subtle land subsidence has been investigated. A time series of ERS-1/2 SAR data from February 1993 to February 2000 is collected from measurements taken in Suzhou city, Jiangsu Province, china, eight ERS-1/2 SAR images are used to create seven interferograms, and three differential interferograms are produced using the three-pass method, which clearly show the spatial extent of land subsidence. The deformation maps are validated by leveling surveys, the correlation coefficient and standard deviation between them are 0. 943 and 0.1706 respectively. Based on seven benchmarks, the subsidence rates are estimated, the overall trends are in close agreement with InSAR results. The results of study show that for the mapping of land subsidence in urban environments InSAR has a strong potential due to its cost-saving, high res

关键词： SAR interferometry land subsidence Suzhou.

Risk analysis for the highly pathogenic avian influenza in china's mainland using meta-modeling

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science Bulletin 2010年第36期 4169-4179页

作者： CAO ChunXiang1, XU Min1,3, CHANG ChaoYi1,3, XUE Yong1, ZHONG ShaoBo1, FANG LiQun2, CAO WuChun2, ZHANG Hao1, GAO MengXu1,3, HE QiSheng1,3, ZHAO Jian1,3, CHEN Wei1,3, ZHENG Sheng1,3 & LI XiaoWen1 1 state key laboratory of remote sensing science, the institute of remote sensing applications of the chinese academy of sciences, beijing 100101, china 2 beijing institute of Microbiology and Epidemiology, state key laboratory of Pathogen and Biosecurity, beijing 100071, china 3 Graduate university of the chinese academy of sciences, beijing 100049, china

A logistic model was employed to correlate the outbreak of highly pathogenic avian influenza (HPAI) with related environmental factors and the migration of birds. Based on MODIS data of the normalized difference vegetation index, environmental factors were considered in generating a probability map with the aid of logistic regression. A Bayesian maximum entropy model was employed to explore the spatial and temporal correlations of HPAI incidence. The results show that proximity to water bodies and national highways was statistically relevant to the occurrence of HPAI. Migratory birds, mainly waterfowl, were important infection sources in HPAI transmission. In addition, the HPAI outbreaks had high spatiotemporal autocorrelation. This epidemic spatial range fluctuated 45 km owing to different distribution patterns of cities and water bodies. Furthermore, two outbreaks were likely to occur with a period of 22 d. The potential risk of occurrence of HPAI in china's mainland for the period from January 23 to February 17, 2004 was simulated based on these findings, providing a useful meta-model framework for the application of environmental factors in the prediction of HPAI risk.

关键词： highly pathogenic avian influenza meta-modeling remote sensing geographical information system Bayesian maximum entropy logistic regression spatiotemporal autocorrelation