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

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 250002, 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 environmental 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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The diurnal and seasonal characteristics of urban heat island variation in beijing city and surrounding areas and impact factors based on remote sensing satellite data

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science china Earth sciences 2005年第Z2期48卷 220-229页

作者： ZHANG Jiahua, HOU Yingyu, LI Guicai, YAN Hao YANG Limin & YAO Fengmei The chinese academy of Meteorological sciences, beijing 100081, china The national Meteorological Center, beijing 100081, china The national Satellite Meteorological Center, beijing 100081, china Joint laboratory for Geoinformation{12., The chinese University of Hong Kong, Hong Kong, china Department of Geosciences, Graduate School of chinese academy of sciences, beijing 100039, china The chinese academy of Meteorological sciences Beijing 100081 China The national Meteorological Center Beijing 100081 China The national Satellite Meteorological Center Beijing 100081 China Joint laboratory for Geoinformation science The Chinese University of Hong Kong Hong Kong China

Based on the land surface temperature (LST), the land cover classification map,vegetation coverage, and surface evapotranspiration derived from EOS-MODIS satellite data, and by the use of GIS spatial analytic technique and multivariate statistical analysis method, the urban heat island (UHI) spatial distribution of the diurnal and seasonal variabilities and its driving forces are studied in beijing city and surrounding areas in 2001. The relationships among UHI distribution and landcover categories, topographic factor, vegetation greenness, and surface evapotranspiration are analyzed. The results indicate that: (i) The significant UHI occur in beijing city areas in the four seasons due to high heat capacity and multi-reflection of compression building, as well as with special topographic features of its three sides surrounded by mountains,especially in the summer. The UHI spatial distribution is corresponding with the urban geometry structure profile. The LST difference is approximately 4-6℃ between beijing city and suburb areas, comparatively is 8- 10℃ between beijing city area and outer suburb area in northwestern regions. (ii) The UHI distribution and intensity in daytime are different from nighttime in beijing city area, the nighttime UHI is obvious. However, in the daytime, the significant UHI mainly appears in the summer, the autumn takes second place, and the UHI in the winter and the spring seem not obvious. The surface evapotranspiration in suburb areas is larger than that in urban areas in the summer, and high latent heat exchange is evident, which leads to LST difference between city area and suburb area. (iii) The reflection of surface landcover categories is sensitive to the UHI, the correlation between vegetation greenness and UHI shows obviously *** scatterplot shows that there is the negative correlation between NDVI and LST (R2 = 0.6481).The results demonstrate that the vegetation greenness is an important factor for reducing the UHI,and la

关键词： urban heat island, vegetation cover, LST, MODIS, beijing city and surrounding areas.

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Automated detection of lunar craters based on object-oriented approach

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chinese science Bulletin 2008年第23期53卷 3699-3704页

作者： YUE ZongYu1,2,3,4, LIU JianZhong3 & WU GanGuo2 1 Institute of remote sensing Application, chinese academy of sciences, beijing 100101, china 2 china University of Geosciences (beijing), beijing 100083, china 3 national Astronomical Observatories of chinese academy of sciences, beijing 100012. china 4 Department of Geological sciences, The University of Texas at San Antonio, San Antonio, TX 78249, U.S.A Institute of remote sensing Application Chinese Academy of Sciences Beijing 100101 China china University of Geosciences (beijing) Beijing 100083 China national Astronomical Observatories of chinese academy of sciences Beijing 100012 China Department of Geological sciences The University of Texas at San Antonio San Antonio TX 78249 USA

The object-oriented approach is a powerful method in making classification. With the segmentation of images to objects, many features can be calculated based on the objects so that the targets can be distinguished. However, this method has not been applied to lunar study. In this paper we attempt to apply this method to detecting lunar craters with promising results. Craters are the most obvious features on the moon and they are important for lunar geologic study. One of the important questions in lunar research is to estimate lunar surface ages by examination of crater density per unit area. Hence, proper detection of lunar craters is necessary. Manual crater identification is inefficient, and a more efficient and effective method is needed. This paper describes an object-oriented method to detect lunar craters using lunar reflectance images. In the method, many objects were first segmented from the image based on size, shape, color, and the weights to every layer. Then the feature of "contrast to neighbor objects" was selected to identify craters from the lunar image. In the next step, by merging the adjacent objects belonging to the same class, almost every crater can be taken as an independent object except several very big craters in the study area. To remove the crater rays diagnosed as craters, the feature of "length/width" was further used with suitable parameters to finish recognizing craters. Finally, the result was exported to ArcGIS for manual modification to those big craters and the number of craters was acquired.

关键词：自动化检测月球环形山地貌

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Characteristics of Earthquake-Triggered Landslides and Post-Earthquake Debris Flows in Beichuan County

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Journal of Mountain science 2010年第3期7卷 246-254页

作者： ZHUANG Jianqi CUI Peng HU Kaiheng CHEN Xiaoqing GE Yonggang key laboratory of Mountain Hazards and Land Surface Processes and Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of chinese academy of sciences Beijing 100049 China

Field investigations and aerial photography after the earthquake of May 12. 2008 show a large number of geo-hazards in the zone of extreme earthquake effects. In particular, landslides and debris flows, the geo-hazards that most threaten post-disaster reconstruction, are widely distributed. We describe the characteristics of these geo-hazards in Beichuan County using high-resolution remote sensing of landslide distribution, and the relationships between the area and volume of landslides and the peak-discharges of debris flows both pre- and post-earthquake. The results show： 1） The concentration （defined as the number of landslide sources per unit area： Lc） of earthquake- triggered landslides is inversely correlated with distance from the earthquake （DF） fault. The relationship is described by the following equation： Lc = 3.2264exp（-0.0831DF）（R2 = 0.9246）; 2） 87 % of the earthquake-triggered landslides were less than 15× 10^4 m2 in area, and these accounted only for 5o% of the total area; 84% of the landslide volumes were less than 60×10^4 m3, and these accounted only for 50% of the total volume. The probability densities of the area and volume distributions are correlated： landslide abundance increases with landslide area and volume up to maximum values of 5 ×10^4m2 and 30 ×10^4 m3, respectively, and then decreases exponentially. 3） The area （AL） and volume （VL） of earthquake-triggered landslides are correlated as described with the following equation： VL=6.5138AL1.0227 （R2 = 0.9231）; 4）Characteristics of the debris flows changed after the earthquake because of the large amount of landslide material deposited in the gullies. Consequently, debris flow peak-discharge increased following the earthquake as described with the following equation： Vpost = 0.8421Vprel-0972 （R2 = 0.9821）（Vpre is the peak discharge ofpre-earthquake flows and the Vpost is the peak discharge of post-earthquake flows）. We obtained the distribution of the landslides based on the above anal

关键词： 5.12.earthquake Landslide Debris flow Magnitude Beiehuan County

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A distributed spatial computing prototype system in grid environment

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science china(Technological sciences) 2010年第S1期53卷 25-32页

作者： WU Lun,YAN MengLong,GAO Yong,YANG ZhenZhen,ZHAO Yong & CHEN Bin Institute of remote sensing and Geographic Information System,Peking University,beijing 100871,china 1. Institute of remote sensing and Geographic Information System Peking University Beijing 100871 China

Digital Earth has been a hot topic and research trend since it was proposed,and Digital china has drawn much attention in *** a key technique to implement Digital china,grid is an excellent and promising concept to construct a dynamic,inter-domain and distributed computing *** is appropriate to process geographic information across dispersed computing resources in networks effectively and cooperatively.A distributed spatial computing prototype system is designed and implemented with the Globus *** important aspects are discussed in *** architecture is proposed according to the characteristics of grid firstly,and then the spatial resource query and access interfaces are designed for heterogeneous data *** open-up hierarchical architecture for resource discovery and management is represented to detect spatial and computing resources in grid.A standard spatial job management mechanism is implemented by grid service for convenient *** addition,the control mechanism of spatial datasets access is developed based on *** prototype system utilizes the Globus Toolkit to implement a common distributed spatial computing framework,and it reveals the spatial computing ability of grid to support Digital china.

关键词： distributed geographic information processing grid computing Digital china GIS

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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

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Features and trends of the environmental change in the arid areas in Central Asia

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science china Earth sciences 2007年第S1期 142-148页

作者： ZHOU KeFa1,2, ZHANG Qing3, CHEN Xi1 & SUN Li1 1 Xinjiang Institute of Ecology and Geography, chinese academy of sciences, ürümqi 830011, china 2 Graduate University of chinese academy of sciences, beijing 100049, china 3 Institute of remote sensing and Geographical Information System, Peking University, beijing 100871, china

RS-monitoring index systems of ecological environment changes at a large scale, based on empirical data and trends in environmental change in Central Asia, are developed using NOAA and MODIS data. Moreover, with the help of mathematical statistics and GIS spatial analysis, the degrees, hazards and distribution extent of various possible ecological problems are discussed, environmental changes in Central Asia in 1990 and 2005 are separately evaluated, and dynamic changes in the environment in Central Asia over a 15-year period are analyzed. The results reveal that during the 15-year period from 1990 to 2005, areas of degenerated vegetation in Kazakhstan, Uzbekistan, Turkmenistan, Kirghizstan and Tadzhikistan were enlarged by 0.069×105 km2, 0.081×105 km2, 0.296×105 km2, 0.022×105 km2 and 0.112.105 km2, respectively. The ecological environment in Central Asia was in the state of significant degeneration and even deterioration. This study proves that NOAA and MODIS data can be used to successfully monitor the environment and provide useful results.

关键词： Central Asia ecological environment vegetation coverage GIS RS

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Research on extracting method of micro-scale remote sensing information combination and application in coastal zone

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Acta Oceanologica Sinica 2009年第5期28卷 30-38页

作者： YANG Xiaomei ZHOU Chenghu GONG Jianming GAO Zhenyu Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Due to the need of rapid and sustainable development in china’s coastal zones, the high-resolution information theory using data mining technology becomes an urgent research focus. However, the traditional pixel-based image analysis methods cannot meet the needs of this development trend. The paper attempts to present an information extraction approach in terms of image segmentation based on an object-oriented algorithm for high-resolution remote sensing images. An aim of the author’ research is to establish an identification system of ＂pixel-primitive-object＂. Through extraction and combination of micro-scale coastal zone features, some objects are classified or recognized, e.g., tidal flat, water line, sea wall, and mariculture pond. Firstly, the authors extract various internal features of relatively homogeneous primitive objects using an image segmentation algorithm based on both spectral and shape information. Secondly, the features of those primitives are analyzed to ascertain an optimal object by adopting certain feature rules. The results from this research indicate that our model is practical to realize and the extraction accuracy of the coastal information is significantly improved as compared with the traditional approaches. Therefore, this study provides a potential way to serve the author’ highly dynamic coastal zones for monitoring, management, development and utilization.

关键词： Object-oriented Image Segmentation Coastal Zone Information Extraction

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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 100029,china 2 Center for Earth Observation and Digital Earth,chinese academy of sciences,beijing 100190,china 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-sensing 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-sensing 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 model and dynamic mechanism for seasonal changes of the euphotic depth in the East china Sea

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Progress in Natural science:Materials International 2003年第11期 26-30+81页

作者： LI Guosheng, YANG Shilin and LIANG Qiang(Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china) Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Based on remote sensing data and models, spatial distribution of the monthly euphotic depth in the East china Sea in 1998 has been obtained. The character of the seasonal changes of the euphotic depth is summarized, and the dynamic mechanism of the key influencing factors is analyzed. The results indicate that the controlling factors of the seasonal changes of euphotic depth in the East china Sea are the seasonal changes of temperature, diluted water from the Yangtze River, the ocean currents and the front process of different water masses.

关键词： East china Sea euphotic depth remote sensing dynamic mechanism.

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