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Formation and causes of NOx pollution on the east side of the Taihang Mountains in China

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Science Bulletin 2011年第19期 2046-2051页

作者： TIAN HeZhong 1 , WANG Yan 1 , ZHAO Dan 1 , CHAI FaHe 2., XING ZiShan 3.& CHENG Ke 1 1 State Key Joint Laboratory of Environmental Simulation & Pollution Control, School of Environment, beijing normal {2.,{4., China 2.Chinese Research Academy of Environmental Sciences, beijing 100012. China 3.School of Computer Science and Technology, beijing {2. of Posts and Telecommunications, beijing 100876, China

Tropospheric column amounts of NO 2.from OMI/Aura products were applied to investigate the seasonal variation of NO x on the east side of the Taihang Mountains (ESTM) in China. The NO 2.concentration varied seasonally, with winter maxima and summer minima. To explore the causes of the heavy NO 2.pollution in this region, wind field simulations were conducted by using the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5). MM5 simulations showed that wind directions in the ESTM region were dominated by northeasterly and northwesterly winds throughout the year and to a lesser degree by southwesterlies. Elevated NO 2.concentrations (higher than 50×10 15 molec/cm 2.) occurred in three meteorological situations: convergent wind fields (5 days), northeasterly winds (2.days), and calm days (1 day) in January. Although the local anthropogenic NO x emission strength was not so high as that in other developed areas, the calms and frequent occurrence of convergent wind fields, as well as unfavorable terrains for diffusion, resulted in the accumulation of atmospheric pollutants and hence heavy NO x pollution. Furthermore, long-distance NO x transportation from the beijing-Tianjin-Tangshan region to the ESTM area could be seen when the wind was from a northeasterly direction, especially under high wind speeds.

关键词： east side of the Taihang Mountains (ESTM) remote sensing of air pollution satellite data tropospheric NO 2 pollution wind field China

Study on the Ecosystem Sustainability of Jing River Basin on Climatic Warming-drying Trend

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Study on the Ecosystem Sustainability of Jing River Basin on...

黄土沟壑丘陵区退耕对土壤侵蚀影响的模拟研究

第三世界生态高峰会

作者： Yin Jing Qiu Guoyu College of Resources Science and Technolgy,beijing normal {2..beijing {4.,China

It is obvious that the climatic trend in the Western China is warming-drying in recent fifty years,especially in Yellow River Basin. Under the impact of climate change and human's activities,its fragile ecosystem became more *** River is one of the main tributary of the Wei River and second-grade tributary of tYellow River. Jing River originated from the Loess Plateau,and its full length and basin area are 4.5.1 km and 4.4.0} *** on meteorological,hydrographic and {3. sensing data collection of nearly fifty years （1955-2.02.,this paper applied the SWAT MODEL （Soil and Water Assessment Tool） to research ecosystem characteristics of Jing River Basin on the conditions of climatic warming-drying trend and aggravated human activities,The impact degree between climate change and human activities to the soil and water resources of Jing River Basin from 1955 to 2.02.were 2.3.especially in 70s～80s,land use and land cover change caused by human activities had much influences on the runoff..Aim to increasing water resources to adapt climatic warming-drying trend in Jing River Basin,the land use patterns were extracted.

关键词： Jing River Basin ecological system runoff land use and land cover change

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水土保持学报 2004年第1期18卷 74-77,81页

作者：李双才罗利芳张科利邱扬刘宇北京大学遥感与地理信息系统研究所北京100871 北京师范大学资源与环境科学系北京100875

随着在黄土沟壑丘陵区退耕政策的实施,退耕必将对该地区的水土流失特征产生重大影响。对退耕的水土保持效益进行模拟研究,可为退耕政策的合理实施提供理论依据。选定位于黄土沟壑丘陵区的安塞研究区,在RS和gis支持下,采用USLE,模拟研究... 详细信息

随着在黄土沟壑丘陵区退耕政策的实施,退耕必将对该地区的水土流失特征产生重大影响。对退耕的水土保持效益进行模拟研究,可为退耕政策的合理实施提供理论依据。选定位于黄土沟壑丘陵区的安塞研究区,在RS和gis支持下,采用USLE,模拟研究了不同退耕方案对土壤侵蚀的影响。在2.01年土地利用的遥感解译图和gis计算分析基础上设计了8种不同的退耕方案,模拟结果显示,各种退耕方案对土壤侵蚀的减少主要发生在强度及强度以上侵蚀区,退耕后研究区已没有发生剧烈侵蚀的区域,强度和极强度侵蚀明显减少;土壤侵蚀量的减少主要发生在≥2.°退耕和≥15°退耕,≥2.°退耕还草和还林分别使土壤侵蚀总量减少了19.9%和2..2.,≥15°退耕还草和还林分别使土壤侵蚀总量减少了3..6%和4.1}6%。≥8°退耕方案和全部退耕方案与≥15°退耕方案相比,水保效益并没有显著差别。

关键词：黄土沟壑丘陵区退耕还林土壤侵蚀模拟分析

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

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

中国科学院地质与地球物理研究所2.07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 982.,beijing 10002.,PR China b State Key Laboratory of {3. {2. Science,Jointly Sponsored by the Institute of {3. {2. Applications of Chinese Academy of Sciences and beijing normal university,beijing 100101,PR China c Department of Mathematics,Liaocheng university,Shandong 2.2.59,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 3.8 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

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Using hyperspectral indices to estimate foliar chlorophyll a...

中国北方13.土地利用景观格局变化分析(19891999)

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 {3. normal {2. No.19 Xinjiekouwai Street{3.,China 2.State Key Laboratory of Earth Surface Processes and Resource Ecology {3. normal {2. No.19 Xinjiekouwai Street{3.,China 3.College of Information & Electrical Engineering China Agricultural {2. {3. 100083.China 4.National Engineering Research Center for Information Technology in Agriculture {3. 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 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.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.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.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.

基于空间分析的机井管理系统总体设计及其关键技术探讨

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水文地质工程地质 2004年第1期31卷 101-104页

作者：赵祥张晔刘素红北京师范大学资源环境系遥感与gis研究中心北京100875 天津市龙脉水资源咨询中心天津300060

在gis空间分析技术支持下 ,对机井管理系统从总体设计、系统功能结构、数据库建库方法、系统实现等多方面进行了阐述 ,并探讨了系统开发的关键技术和主要的程序编码 ,在机井管理信息化方面进行了有益的尝试 ,为建立类似系统提供了一个... 详细信息

在gis空间分析技术支持下 ,对机井管理系统从总体设计、系统功能结构、数据库建库方法、系统实现等多方面进行了阐述 ,并探讨了系统开发的关键技术和主要的程序编码 ,在机井管理信息化方面进行了有益的尝试 ,为建立类似系统提供了一个应用范例。

关键词：空间分析机井管理系统设计数据库总体设计管理信息化地下水资源管理

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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2.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2.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2.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2.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

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地物波谱数据仓库系统设计研究

计算机工程与应用 2003年第33期39卷 199-201页

作者：帅艳民朱启疆王培娟王锦地刘素红白香花北京师范大学遥感与gis研究中心资源与环境科学系环境遥感与数字城市北京市重点实验室北京100875

典型地物波谱特征是遥感仪器波段选择的依据,是遥感解译的基础。我国已经积累了大量的地物波谱数据,而且即将获得更多的地物波谱数据。如何有效地管理数据?从观测波谱数据中挖掘出观测间隙的波谱数据?该文按照参数配套原则,提出用树状... 详细信息

典型地物波谱特征是遥感仪器波段选择的依据,是遥感解译的基础。我国已经积累了大量的地物波谱数据,而且即将获得更多的地物波谱数据。如何有效地管理数据?从观测波谱数据中挖掘出观测间隙的波谱数据?该文按照参数配套原则,提出用树状结构的事实表和分维表实现数据管理。基于相关作物模型和数据挖掘方法采掘观测间隙的光谱数据,并用北京顺义野外实验SE590波谱数据为实例介绍一种地物波谱数据仓库系统的设计。

关键词：数据仓库数据挖掘数据库分维表事实表