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Discussion on Evolution of Land-use Planning in china

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china City Planning Review 2009年第1期18卷 32-37页

作者： CAI Yumei,Land Planning Department,Land Investigation and Planning Institute of china,beijing,P.R.china. ZHANG Wenxin,geography and RS Science School,beijing normal university,beijing,P.R.china. ZHAO Yanwen,Resource and Environment Science college,Nanjing Agricultural university,Nanjing,P.R.china. SHI Ke

The classical definition of land-use plan was brought forward by Kent in 1964, which is"the official statement of a…legislative body which sets forth its major policies concerning desirable future physical developmen... 详细信息

关键词： farmland official statement regulations concerning

Using hyperspectral indices to estimate foliar chlorophyll a concentrations of winter wheat under yellow rust stress

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Using hyperspectral indices to estimate foliar chlorophyll a...

土壤侵蚀信息熵:单元地表可蚀性的综合度量指标

The First International Conference on Computers and Computing Technologies in Agriculture

作者： LI JING~(1,2) JIANG JINBAO~1 CHEN YUNHAO~(1,2,*) WANG YUANYUAN~1 SU WEI~3 HUANG WENJIANG~4 1 college of Resources Science and Technology beijing normal university No.19 Xinjiekouwai Street beijing 100875,china 2 State Key Laboratory of Earth Surface Processes and Resource Ecology beijing normal university No.19 Xinjiekouwai Street beijing 100875,china 3 college of Information & Electrical Engineering china Agricultural university beijing 100083,china 4 National Engineering Research Center for Information Technology in Agriculture beijing 100089,china

The canopy hyperspectral reflectance of winter wheat infected with yellow rust at different levels of severity were measured by an ASD FieldSpec Pro FR spectrometer in the field and the concentrations of chlorophyll a(Chl a) in the leaves corresponding to the spectra were determined by biochemical methods in the *** analyses were made between Chl a concentrations and canopy hyperspectral data of diseased wheat. Results show that foliar Chl a concentrations are strongly correlated with canopy spectrum in the visible region and the first-order derivative spectrum in blue edge,green edge,and red *** and nonlinear models for estimating Chl a concentrations of the diseased wheat were built based on several spectral *** indicate that SDr/SDg,in which SDr and SDg are the sums of the first derivative within red and green edges,outperformed the other indices in predicting Chl a *** relative estimation errors for Chl a for 12 unseen samples are 17.5%.It is concluded that derivative spectra in red edge and green edge have strong prediction power for foliar Chl a concentrations of diseased winter *** hyperspectral remote sensing data to monitor crop disease and nutrition status is very promising.

关键词： chlorophyllα estimation models hyperspectral wheat yellow rust stress

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水土保持学报 2002年第A1期16卷 50-53页

作者：朱启疆帅艳民陈雪甘大勇于芳北京师范大学遥感与地理信息系统研究中心北京100875

提出了土壤侵蚀信息熵 (侵蚀熵 )的概念 ,并以公式 H=- cΣni=1 ωiaijlog(ωiaij)来表达。当把侵蚀过程的影响因子分为外部的降雨因子和内部的下垫面因子时 ,侵蚀熵在本质上反映的是土壤侵蚀下垫面可侵蚀性的综合信息。侵蚀熵模型可用... 详细信息

提出了土壤侵蚀信息熵 (侵蚀熵 )的概念 ,并以公式 H=- cΣni=1 ωiaijlog(ωiaij)来表达。当把侵蚀过程的影响因子分为外部的降雨因子和内部的下垫面因子时 ,侵蚀熵在本质上反映的是土壤侵蚀下垫面可侵蚀性的综合信息。侵蚀熵模型可用于土壤侵蚀过程的空间数字模拟 ,预测水土保持措施的客观效果。侵蚀熵模型与降雨侵蚀力 R(R=EI30 )的乘积γHR(γ为因次换算系数 ) 。

关键词：土壤侵蚀侵蚀因子侵蚀模型土壤侵蚀信息熵遥感

中国北方13省土地利用景观格局变化分析(19891999)

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水土保持学报 2005年第5期19卷 143-146页

作者：李月臣宫鹏陈晋刘春霞何春阳环境演变与自然灾害教育部重点实验室北京师范大学资源学院北京100875 遥感科学国家重点实验室中国科学院遥感应用研究北京100101 重庆师范大学地理科学学院重庆400047

以北方13省为研究区,对该区1989～1999年的宏观土地利用景观格局变化进行了分析.结果表明:决定该区景观格局的主体要素类型为草地、难利用地和林地,其次为耕地.1989～1999年期间,区内景观异质性程度在逐渐提高, 土地利用向着多样化和均... 详细信息

以北方13省为研究区,对该区1989～1999年的宏观土地利用景观格局变化进行了分析.结果表明:决定该区景观格局的主体要素类型为草地、难利用地和林地,其次为耕地.1989～1999年期间,区内景观异质性程度在逐渐提高, 土地利用向着多样化和均匀化方向发展.景观空间格局变化特征是:耕地、林地和城镇用地破碎度最大;林地、草地和水域受到人类活动的严重干扰,斑块空间分布不断分散和破碎化,分离度和破碎度指标增加.草地的破碎度增加最为显著,严重影响该区农牧业的正常生产.景观要素之间的转化关系主要表现为林、草地和耕地之间的相互转化,以及草地退化为难利用地.表征了该区生态建设实践和生态破坏活动的相互作用以及草地的严重退化趋势,说明北方13省存在较为严重生态环境问题,急需解决.

关键词：景观格局变化土地利用北方13省

Pollen indication to source plants in the eastern desert of china

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Science Bulletin 2005年第15期 98-107页

作者： LI Yuecong1,2, XU Qinghai2, ZHAO Yingkui3, YANG Xiaolan4, XIAO Jule1, CHEN Hui2,5 & Lü Xinmiao5 1. Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 100029, china 2. college of Resources and Environment, Hebei normal university, Shijiazhuang 050016, china 3. Department of Environmental Management, university of Central Lancashire, Preston, UN 4. Hebei geography Institute, Hebei Academy of sciences, Shijiazhuang 050011, china 5. Institute of Geographical sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, china

In order to investigate the indication of major pollen types to source plants, 39 surface pollen samples are collected from 39 plant communities. The results show that diversity of pollen assemblages presents in different commu-nities. Chenopodiaceae pollen percentages are highest in Kalidium communities and Ceratoides communities (higher than 45%, average is 63.4%), but high Ephedra pollen per-centages (higher than 3.3%, average is 16.5%)in Ceratoides communities make it distinguished from Kalidium communi-ties. Artemisia pollen percentages (more than 50%) are much higher than Chenopodiaceae (less than 35%) in Artemisia Communities. Nitraria pollen percentages (higher than 2%, average is 13.6%) are highest in Nitraria communities com-pared with those in other community patterns. Tamariceae pollen percentages (higher than 2%, average is 8.6%) are highest both in Tetraena and Reaumuria communities com-pared with those in other community patterns. But in Reau-muria communities, Artemisia pollen percentages are higher than Chenopodiaceae with some other pollen types such as Gramineae, Compositae, Leguminosae; on the contrary, in Tetraena communities, Artemisia pollen percentages are less than Chenopodiaceae with few other pollen types. Calli-gonum pollen only appears in Calligonum communities (higher than 2%,average is 5%). The results of cluster analysis (CLA) and detrended correspondence analysis (DCA) show that the pollen indication to source plants can be reflected by association indices (A), over-representation in-dices (O), under-representation indices (U), R-value, the av-erage pollen percentages where parent plants are absent (Xa) and the average pollen percentages where parent plants are present (Xp). Zygophyllum, Calligonum, Tetraena, Tribulus and Tamariceae can indicate source plants very well, owing to high A scores. Artemisia, Chenopodiaceae and Gramineae have high R-values, and Nitraria, Cruciferae and sedum have high O scores, so they are over-represente

关键词： eastern desert of china pollen indication association indices (A) over-representation indices (O) under-representation indices (U) correlation coefficients (CC) similarity coefficients (C) detrended correspondence analysis (DCA) cluster analysis (CLA) ratios of Nitraria and Ephedra (N/E) ratios of Ephedra and Artemisia (E/A) ratios of Artemisia and Chenopodiaceae (A/C).

Cloning and Expression Analysis of the Hexokinase Family in the Developing Spikelets of Rice (Oryza sativa L.)

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Cloning and Expression Analysis of the Hexokinase Family in ...

remote sensing and geographic information systems in the spatial temporal dynamics modeling of infectious diseases

The Second International Symposium on Plant Neurobiology

作者： Wei Cheng, Xiaojin Zhou, Jie Li, Chao Chen, Yingdian Wang Laboratory of Plant Development Physiology and Molecular Biology, college of Life sciences, beijing normal university, 19XinJieKouWai Avenue, beijing 100875, china

The carbon metabolism and sugar signal transduction is critical in the plant growth and development processes. Plant hexokinase not only catalyzes the production of hexose 6-phosphates but also acts as a sugar sensor plays an important role in sugar sensing and signaling (Jang et al. 1997: Coruzzi and Bush, 2001;Moore et al.,2003).

关键词：

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Science china(Life sciences) 2006年第6期49卷 573-582页

作者： GONG Peng 1,XU Bing 2 & LIANG Song 1、3 1. State Key Laboratory of remote sensing Science,Jointly Sponsored by the Institute of remote sensing Applications,Chi-nese Academy of sciences and beijing normal university,Box 9718,beijing 100101,china 2. Department of geography,university of Utah,Salt Lake City,UT 84112,USA 3. School of Public Health,university of California,Berkeley,CA 94720,USA 1. State Key Laboratory of remote sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Box 9718 Beijing 100101 China 2. Department of geography University of Utah Salt Lake City UT 84112 USA 3. School of Public Health University of California Berkeley CA 94720 USA

Similar to species immigration or exotic species invasion,infectious disease transmis-sion is strengthened due to the globalization of human activities. Using schistosomiasis as an exam-ple,we propose a conceptual model simulating the spatio-temporal dynamics of infectious diseases. We base the model on the knowledge of the interrelationship among the source,media,and the hosts of the disease. With the endemics data of schistosomiasis in Xichang,china,we demonstrate that the conceptual model is feasible; we introduce how remote sensing and geographic information systems techniques can be used in support of spatio-temporal modeling; we compare the different effects caused to the entire population when selecting different groups of people for schistosomiasis control. Our work illustrates the importance of such a modeling tool in supporting spatial decisions. Our mod-eling method can be directly applied to such infectious diseases as the plague,lyme disease,and hemorrhagic fever with renal syndrome. The application of remote sensing and geographic informa-tion systems can shed light on the modeling of other infectious disease and invasive species studies.

关键词： spatio-temporal modeling, spatial connectivity, prevention and control of infectious diseases, biological invasion.

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

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土壤的多角度偏振反射光谱研究

土壤学报 2004年第3期41卷 476-479页

作者：赵虎晏磊赵云升北京大学遥感与地理信息系统研究所北京100871 东北师范大学地理系长春130024

在利用多波段、多时相、高光谱的遥感数据来提高遥感对地物的识别能力的同时~[1]，人们注意到角度信息在遥感图像识别和分类中起到的影响和贡献~[2]，即地物在2π空间上的三维光谱特征。在早期的遥感，主要采取垂直收集对地观测数据。... 详细信息

在利用多波段、多时相、高光谱的遥感数据来提高遥感对地物的识别能力的同时~[1]，人们注意到角度信息在遥感图像识别和分类中起到的影响和贡献~[2]，即地物在2π空间上的三维光谱特征。在早期的遥感，主要采取垂直收集对地观测数据。根据不同的地物具有不同的吸收、反射和发射电磁波的能力，来分辨地球表层的地物分布。这里基于一个假定：假定目标地物的反射光谱在2π空间内分布是一致的(朗伯体)。随着遥感的深入，这种假定引发的结论与实际相差较大。而且在单一角度下常出现不同地物对应相同的光谱反射率，上述方法存在误判。如果从多个角度来观测地物，不同地物在多角度下具有相同光谱反射率的几率会大大缩小。其次不同地物的物质成分、颜色、结构、构造的不同，其光谱的偏振态以及在2π空间的三维光谱特征都存在差异。通过这些差异，对于精确识别地物，提高遥感的实际应用具有重要意义。

关键词：土壤多角度偏振反射光谱遥感图像识别图像分类地物