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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 {1. interpretation of geomorphological changes in the intertidal zone.

关键词： waterline water level variations exposure patterns central Jiangsu coast remote {1.

Calculating soil moisture by remote {1. and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1.& LIU Changming1. 2 1. School of Environmental Sciences, Beijing Normal University, Beijing 1.0875, china 2. Institute of Geographic Science and Natural Resources Research, Beijing 1.01.1. china Beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote {1. data, soil moisture, precipitation and evaporation during the period of 1.82—1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote {1. model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82 to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote {1. and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3. the evapotranspiration of 3.00-3.00 km3. and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

Status and Perspectives of SNPS applications in china

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Status and Perspectives of SNPS applications in China

Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW china

2005中国卫星应用大会

作者： Dr. Jing Guifei National remote {1. center of {3.

＜正＞National Medium and Long-term S＆T Development Plan The first National Medium and Long-term S＆T Development Plan of the century is directly connected with the realization of building a well-off society As one of the priorities, Space technology and its applications has been paid more attention in the plan. It aims: enhance independent innovation capabilities become a master of a group of kernel technologies build a group of enterprises and brands with international competitiveness With reference of these aims, some perspectives are reminded here.

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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 {1. 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

利用弯曲度半径复函数构建综合面实体相似度模型

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测绘学报 2013年第1期42卷 145-151页

作者：付仲良逯跃锋武汉大学遥感信息工程学院武汉大学测绘遥感信息工程国家重点实验室

面实体的边界线在某点两侧割线夹角是对边界线在该点的弯曲程度和凸凹性的反映,该点与其所在几何实体边界线的中心距离又可以对面实体形状的整体进行描述,通过边界线上某点的中心距离和夹角组成复数,并对其进行快速傅里叶变换得到傅里... 详细信息

面实体的边界线在某点两侧割线夹角是对边界线在该点的弯曲程度和凸凹性的反映,该点与其所在几何实体边界线的中心距离又可以对面实体形状的整体进行描述,通过边界线上某点的中心距离和夹角组成复数,并对其进行快速傅里叶变换得到傅里叶变换系数,利用傅里叶系数构造描述形状的特征向量,该向量即为傅里叶形状描述子,作为对面实体形状相似度的度量。将面实体的空间位置、形状、大小等相似度通过加权综合获得一种综合空间相似度度量模型,利用此模型对面实体进行匹配试验结果表明,本文算法能够有效地进行面实体的匹配。

关键词：弯曲度中心距离复函数傅里叶形状描述子面实体匹配

Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin

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Science china Earth Sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1. LU QiFeng2, GAO ZhiQiang3.& PENG Jian4 1.School of Water Resource and Hydropower, Sichuan University, Chengdu 61.065, {1. 2 National Satellite Meteorological center, {1. Meteorological Administration, Beijing 1.0081. {1. 3.Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. {1. 4 School of Environmental Sciences, Peking University, Beijing 1.0871. {1. 1. School of Water Resource and Hydropower Sichuan University Chengdu 610065 China 2. National Statellite Meteorological center China Meteorological Administration Beijing 100081 China 3. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 4. School of Environmental Sciences Peking University Beijing 100871 China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001.2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

Chinese HJ-1./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 1.0029,{1. 2 center for Earth Observation and Digital Earth,Chinese Academy of Sciences,Beijing 1.01.0,{1. 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-{1. applications,this article explains the overall technical characteristics of the Chinese HJ-1. and HJ-1. *** 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-{1. 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-1. and HJ-1. satellite data.

关键词： HJ-1./B application remote sensing characteristics

Study of evolution forecast of the area of the Huanghe River mouth

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Acta Oceanologica Sinica 1993年第2期12卷 249-259页

作者： Guo Yongsheng, Xu Xuegong, Fan Zhaomu, Wu Peihong and Zhu Xiaoge Department of Geography, Shandong Normal University, Jinan 25001., china Department of Geography, Peking University, Beijing 1.0871. china remote {3. geology Department, Oil Exploration and Exploitation Scientific Research Institute, Beijing 1.0083. china Department of Geography Shangdong Normal University Linan 250014 China China

From 1.79 to 1.89, the current Qingshuigou course of the Huanghe River formed a sub - delta which resembles a beak extending into the Laizhou Bay. It covers 61. km2 in area. To meet the needs of developing and constructing the Huanghe River Delta and under the presupposition of keeping the current course for 1.-20 a, we forecast mainly by using the OM (1. 1. model that the front border of the sub-delta will be close to 1.9°3.'E and its area will become 923.km2by the end of the year 2000. The Huanghe River will make land 760 km2 in area.

关键词： Huanghe River mouth Markov chain forecasting method of grey number series

THE DEEP-SEATED GEOLOGICAL STRUCTURE AND ITS EVOLUTION IN LUOBUBO—ALASHAN REGION

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THE DEEP-SEATED GEOLOGICAL STRUCTURE AND ITS EVOLUTION IN LU...