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Spatial variations of tidal water level and their impact on the exposure patterns of tidal land on the central Jiangsu coast

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Acta Oceanologica Sinica 2010年第1期29卷 79-87页

作者： WANG Zhenyan GAO Shu HUANG Haijun key laboratory of Marine Geology and environment Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China MOE key laboratory for Coast and Island Development Nanjing University Nanjing 210093China

The exposed area of intertidal zone varies with tidal water level changes, If intercomparisons of satellite images are adopted as a method to determine geomorphological changes of the intertidal zone in response to accretion or erosion processes, then the effect of water level variations must be evaluated. In this study, two Landsat TM images overpassing the central Jiangsu coastal waters on 2 January and 7 March 2002, respectively, were treated by the changing detection analysis using Image Differencing and Post-classification Comparison. The simultaneous tide level data from four tide gauge stations along the coast were used for displaying the spatial variations of water levels and determining the elevations of waterlines. The results show that the spatial variations of water levels are highly significant in the central Jiangsu coastal waters. The huge differences of tidal land exposure patterns between the two imaging times are related mainly to the spatial variations of tidal water levels, which are controlled by the differences in tidal phases for different imaging times and the spatial variations of water level over the study area at each imaging time. Under complex tidal conditions, e.g., those of the central Jiangsu coastal waters, the tide-surge model should be used to eliminate effectively the effects of water level variations on remote sensing interpretation of geomorphological changes in the intertidal zone.

关键词： waterline water level variations exposure patterns central Jiangsu coast remote sensing

使用PB数据管道对象实现多数据库备份与更新

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计算机工程与应用 2004年第26期40卷 163-165页

作者：赵祥刘素红屈永华王培娟北京师范大学地理学与遥感科学学院遥感与地理信息系统研究中心北京100875 北京师范大学地理学与遥感科学学院遥感科学国家重点实验室北京100875 北京师范大学地理学与遥感科学学院环境遥感与数字城市北京市重点实验室北京100875

论文介绍了PowerBuilder数据管道(DataPipeline)对象的主要特点与作用,结合数据库存储过程的使用,提出后台多数据库备份与更新的策略及关键技术,并给出其实现方法,为多数据库维护与使用提供了一个实例。

关键词： PowerBuilder数据管道多数据库备份与更新

Study of spatial distribution of sandy desertification in North china in recent 10 years

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Science china Earth Sciences 2004年第z1期47卷 78-88页

作者： WANG Tao, WU Wei, XUE Xian, SUN Qingwei & CHEN Guangtingkey laboratory of Desert and Desertification, Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 73.000,{3. Department of environment Engineering, Peking University, beijing 100871,{3. Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Key Lab Desert & Desertificat Lanzhou 730000 Peoples R China Peking Univ Dept Environm Engn Beijing 100871 Peoples R China

Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North china. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in china. Rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North china. remote sensing monitored results in 2000 showed that the sandy desertified land area has been 3..57× 104 km2. The area of potential to slightly sandy desertified land is 13.93. 104 km2, moderately land 9.977×104 km2, severely land 7.909 ×104 km2 and very severely land 6.756×104 km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100 km2 ·a-1 in 1976-1988 to 3.600 km2 · a-1 in 1988-2000. The basic status of sandy desertification in North china is 'overall deterioration, while local rehabilitation'. Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North china can be restored under the conditions of rational land-use ways and intensity.

关键词： sandy desertified land, spatial distribution, remote sensing monitoring, last 10 years, North china.

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,{3. 2 Center for Earth Observation and digital Earth,Chinese Academy of Sciences,beijing 100190,{3. 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

Eco-environment evolvement analysis of Ertan reservoir catchment based on remote sensing

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Science china(Technological Sciences) 2011年第S1期54卷 95-100页

作者： PANG ZhiGuo ,GE DeXiang & FU Jun E State key laboratory of Simulation and Regulation of Water Cycle in River Basin,,china Institute of Water Resources and Hydropower Research,{3. 100048,china 1. State key laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100048 China

Hydropower project may bring with it social-economic profits as well as side *** built dam and reservoir often cause some problems to the surrounding areas,among which the ecological and environmental effects caused by hydropower projects are always concerned by the *** this article,we take the Ertan reservoir catchment as the research area and try to quantitatively analyze the variation of vegetation cover and soil erosion by remote sensing technique,and to comprehensively assess the evolvement and development trend of reservoir *** erosion,land use/cover are used as ecological and environmental indicators which reflect the changes before,after and in the period of the construction of Ertan hydropower *** by the multi-source remote sensing data(from satellite Landsat and CBERS) and DEM data,the land use/cover is interpreted through RS images which are classified both by unsupervised and supervised method,and the driving factors of the ecological changes are also *** the same time,the changes of soil loss are also monitored and analyzed during flood seasons of Ertan reservoir area before and after reservoir impoundment(1995,2000 and 2005) using the revised universal soil loss equation(RUSLE) .The results show that during the recent 13.years the arable land area has decreased obviously,and construction area and water surface have increased *** increase of vegetation cover has some relations with the implementation of local ecological projects,i.e.,de-farming to forestry and de-farming to pasture *** the same time,changes may also be caused by the climate adjustment in the reservoir *** the ten years from 1995 to 2005,the high soil loss classes were transforming to lowly level classes *** of these show that the soil loss of Ertan reservoir area is getting better.

关键词： Ertan reservoir catchment eco-environment land use/cover soil loss remote sensing

Ecological Instream Flow Requirements Calculation of Pihe River by Montana Methodology in Sichuan Basin,china

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Ecological Instream Flow Requirements Calculation of Pihe Ri...

Susceptibility Assessment of Landslides Caused by the Wenchuan Earthquake Using a Logistic Regression Model

2007中国科协年会

作者： W.Ouyang~(1,2) F.H.Hao~1 H.Chen~1 X.Wang~1 S.T.Yang~3.1.School of environment,State key laboratory of Water environment Simulation,2.beijing Normal University 2.International Institute for Geo-Information Science and Earth Observation(ITC),Netherlands 3.State key laboratory of remote sensing Science,beijing key laboratory for remote sensing of environment and digital cities,School of Geography,beijing Normal University

With the rapid economic developments in china,the future water resource developments should be sustainable and that a component of the natural flow of rivers should be reserved to ensure diverse ecological *** last 15 years,ecological instream flow requirements(EIFR)research of river was one of the main and hot fields for eco-hydrology *** this paper,we summarized the research advance of eco-hydrology and also,the conception of the EIFR was also followed and *** ecological instream flow has three main functions:maintain the water ecological environments,dilute pollutants and *** coordinate with the water resource allocation,we evaluated EIFR of Pihe River section in every 12 month of three typical years (1968,1986 and 1987).Pihe River is one of the main waterr sources for the cities in Sichuan Basin and locates in the lower beach of famous Doujiang *** Montana methodology was widely applied in water requirements estimate and proved *** on natural characters of Pihe River,minimum and optimum water requirement of aquatic habitat for the river maintenance were *** water requirement of Pihe River was computed too,which is related with the width of water surface,the river length and evaporation depth. Considering the water quality goal,diluting pollutant water requirement was taken into *** the EIFR of the river of 12 month were ultimateS,*** them,that was 20.64m/s and the minimum eco-environmental water requirement of the river was 25.84m/s.

关键词： Eco-environmental water requirements Water resource allocation Water quality goal Pollutant dilute water requirement

来源： cnki会议评论

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Journal of Mountain Science 2010年第3期7卷 234-245页

作者： SU Fenghuan key laboratory of Mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu China Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu China Graduate University of the Chinese Academy of Sciences Beijing China

The Wenchuan earthquake on May 12,2008 caused numerous collapses,landslides,barrier lakes,and debris *** susceptibility mapping is important for evaluation of environmental capacity and also as a guide for post-earthquake *** this paper,a logistic regression model was developed within the framework of GIS to map landslide *** County,a heavily affected area,was selected for the *** of landslides was prepared by interpretation of multi-temporal and multi-resolution remote sensing images(ADS40 aerial imagery,SPOT5 imagery and TM imagery,etc.) and field *** Certainly Factor method was used to find the influencial factors,indicating that lithologic groups,distance from major faults,slope angle,profile curvature,and altitude are the dominant factors influencing *** weight of each factor was determined using a binomial logistic regression *** susceptibility mapping was based on spatial overlay analysis and divided into five *** faults have the most significant impact,and landslides will occur most likely in areas near the *** of the area has a high or very high susceptibility,located in the northeast,south and southwest,including 65.3. of all landslides coincident with the *** susceptibility map can reveal the likelihood of future failures,and it will be useful for planners during the rebuilding process and for future zoning issues.

关键词： Landslide susceptibility WenchuanEarthquake GIS logistic regression certainty factor

基于Multigen/Vega的校园VR仿真系统的实现——以中国矿业大学为例

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系统仿真学报 2004年第9期16卷 1995-1998页

作者：宋金玲肖寒盛业华王锦地北京师范大学地理学与遥感科学学院遥感与地理信息系统研究中心遥感科学国家重点实验室环境遥感与数字城市北京市重点实验室北京100875 中国矿业大学环测学院徐州221008 南京师范大学地理科学学院南京210097

虚拟现实技术对于城市规划和城市的可持续发展有着非常重要的意义,它的长足进步,为真实景观的再现提供了有效手段。本论文在已有的二维地理信息系统数据的基础上进行校园数据的获取与组织,利用虚拟现实技术实现校园全景的三维重建,采用... 详细信息

虚拟现实技术对于城市规划和城市的可持续发展有着非常重要的意义,它的长足进步,为真实景观的再现提供了有效手段。本论文在已有的二维地理信息系统数据的基础上进行校园数据的获取与组织,利用虚拟现实技术实现校园全景的三维重建,采用层次型与面向对象相结合的三维数据结构,构造了校园全景的仿真模型,并实现了校园全景的驱动显示,为校园规划和可持续发展更可靠的保证。

关键词：虚拟现实 Multigen Vega 仿真

Soil Moisture and Oilseed Rape Yields as Affected by Configuration of Ridge-furrow Tillage in the Semiarid Region of china

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Soil Moisture and Oilseed Rape Yields as Affected by Configu...