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

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 {2. of Environmental Simulation & Pollution Control, School of Environment, {2. Normal University, {2. 100875, China 2.chinese Research academy of Environmental sciences, {2. 100012. China 3 School of Computer Science and Technology, {2. University of Posts and Telecommunications, {2. 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

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福建省永安市西洋镇2.5a生人促阔叶林与伐前林分的对比评价

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山地学报 2010年第1期28卷 63-68页

作者：张晓红黄清麟张超中国林业科学研究院资源信息研究所国家林业局林业遥感与信息技术重点实验室西南林学院资源学院

福建省永安市西洋镇2.5a生人促阔叶林分平均胸径、树高、密度、单位面积蓄积量和平均年生长量分别为2.0cm、1.8m、19533株/hm2.7.0m3/hm2.2.80m3/(hm2.a),乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为33、2.93、0.6... 详细信息

福建省永安市西洋镇2.5a生人促阔叶林分平均胸径、树高、密度、单位面积蓄积量和平均年生长量分别为2.0cm、1.8m、19533株/hm2.7.0m3/hm2.2.80m3/(hm2.a),乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为33、2.93、0.62.0.2.,林分相对直径分布范围0.2.～3.00,直径分布为反J型,表现为异龄林特征。35a生的伐前林分平均胸径、树高、密度、单位面积蓄积量和平均年生长量分别为13.6cm、10.5m、1185株/hm2.101.3m3/hm2.2.89m3/(hm2.a),乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为2.、3.72.0.81和0.10,林分相对直径分布范围0.44～2.50,直径分布为反J型,表现为异龄林特征。

关键词：人促阔叶林伐前林分对比评价福建省永安市

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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

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Bi-directional normalized difference vegetation index: concept and application

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Progress in Natural Science:Materials International 2002年第2期 37-41页

作者： LI Xiaowen , GAO Feng , WANG Jindi , YANG Hua, A. STRAHLER and C. SCHAAF( Research Center for remote sensing and Department of Geography, {2. Normal University, {2. 100875, China Department of Geography and Center for remote sensing, Boston University, Boston MA02.15, USA) Research Center for remote sensing and Department of Geography，{2. Normal University，{2. 100875，China Department of Geography and Center for remote sensing，Boston University，Boston MA02.15，USA Department of Geography and Center for remote sensing，Boston University，Boston MA02.15，USA Research Center for remote sensing and Department of Geography，{2. Normal University，{2. 100875，China

The data products of land surface bi-directional reflectance distribution function (BRDF) from the space-borne Polarization and Directionality of the Earth Reflectance (POLDER) of France and the Moderate Resolution Imaging Spectroradiometer (MODIS) of USA are available recently, but the atmospheric correction for meeting the requirement of quantitative remote sensing is still a very difficult problem. This paper presents a concept: bi-directional normalized difference vegetation index (Bi-NDVI), in order to consider simultaneously the effects of both land surface BRDF and atmospheric path scattering. An atmospheric quality index is thus defined for satellite multi-angular observations. The quality of MODIS/BRDF data products can be improved notably through iterative inversion weighed by this index.

关键词： bi-directional reflectance normalized difference vegetation index atmospheric correction.

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Study on the Effects of Natural Factors on Water Conservation Capacity of Qilian Mountain

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Meteorological and Environmental Research 2011年第11期2卷 46-48,63页

作者： GAN Xiao-li 1,SUN De-quan 1,2.3,ZHANG Lin-bo 2.3,JIA Qing-tang 2.3 1.School of Water Resources and Environment,China University of Geosciences,beijing 100083,China 2.{2. {2. of state Environment Protection Regional Eco-process and Function Assessment,beijing 100012.China 3.chinese Research academy of Environmental sciences,beijing 100012.China

[Objective]The study aimed at analyzing the effects of natural factors on water conservation capacity of Qilian Mountain.[Method] Based on water conservation quantity,elevation data and SPOT-VEGETATION remote sensing data of Qilian Mountain in 2.03,the relationship between water conservation quantity and influencing factors like elevation,slope,aspect and vegetation index varying greatly in the studied area was analyzed quantitatively by means of statistical method,and the effects of natural factors on water conservation capacity of Qilian Mountain were discussed on the basis of water conservation capacity.[Result]In water conservation district of Qilian Mountain,water conservation amount was higher in the region with elevation of 3 600-4 2.0 m or slope of 15°-40°;sunny slope (with slope of 90°-180°) and the area with high vegetation coverage had the strongest water conservation capacity.[Conclusion]The research could provide scientific references for the management of water resources and vegetation protection in Qilian Mountain.

关键词： Water conservation amount Qilian Mountain Water conservation capacity China

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南海卫星遥感海表湍流热通量资料的评估

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气候与环境研究 2018年第3期23卷 332-340页

作者：封宝鑫刘海龙林鹏飞王启中国海洋大学海洋和气象学院山东青岛266100 中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室北京100029

利用现场观测资料、OAFlux的湍流热通量,评估了JOFURO(Japanese Ocean Flux Data Sets with use of remote sensing Observations)、HOAPS-2.Hamburg Ocean Atmosphere Parameters and Fluxes from Satellite data version 2.、GSSTF-2.Goddard Satellite-Based Surface Turbulent Fluxes version 2.3种卫星资料在南海区域的表现。3套卫星资料可以说各有千秋,总体而言JOFURO和GSSTF-2.料的空间分布和时间变化与OAFlux资料整体上较一致,但是这两套资料都在很大程度上低估了海盆平均的潜热和感热,前者低估约10%~2.%,后者则可以达到50%以上。HOAPS-2.料与现场观测资料有较好的一致性,但在时间变化上和其他资料的差异则较大,特别是感热方面,季节变化振幅、年际变化位相等都与其他资料不一致。通过比较我们发现,海南岛周边以及南海南部区域估算的潜热和感热释放偏小是造成整体偏小的主要原因。

关键词：卫星遥感湍流热通量潜热通量感热通量南海

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Landscape distribution characteristics of northern foothill belts of Tianshan Mountains

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Journal of Geographical sciences 2002年第1期12卷 23-28页

作者： CHENG Wei-ming, ZHOU Cheng-hu, TANG Qi-cheng, YAO Yong-huiZHANG Bai-ping (state key {2. of Resources and Environment Information System, {2. ofGeographic sciences and Natural Resources Research, CAS, beijing 100101, China) state key {2. of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS Beijing China

The foothill belts of Tianshan Mountains are about 2.0 km long and 60 km wide, and the study area extends from Kuitun city to Fukang city. They are transitional belts between mountains and plains, appearing in three rows of folds with different morphologies and their age becoming younger from south to north. Based on GIS and RS methods, and materials of the previous researchers, this paper deals with the genetics of the foothill belts and their landscape features resulting from folding by neotectonic movements, and also describes their length, width and slope by remote sensing image interpretation. The characteristics of the foothill belts are found to be very important for the surrounding environment by preventing groundwater from flowing into plains, changing groundwater, increasing flow of surface runoff, in addition to their roles in protecting the surrounding environment. The purpose of this paper is to provide an in-depth understanding of the foothill belts and influence on its surrounding environment.

关键词： foothill belts foothill landscape geomorphic landscape geomorphic remote sensing Tianshan Mountains

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黄河流域坡高地系统最小生态需水研究

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山地学报 2004年第2期22卷 154-160页

作者：张远杨志峰北京师范大学环境学院北京师范大学环境学院水环境模拟国家重点实验室水沙科学教育部重点实验室北京 100875 中国环境科学研究院北京 100012水环境模拟国家重点实验室水沙科学教育部重点实验室北京 100875

以保护和恢复流域坡高地生态系统为目的,对坡高地最小生态需水问题进行研究,提出了坡高地生态需水和生态缺水的计算方法。以黄河流域为实例,在GIS和遥感技术支持下对坡高地最小生态需水量和缺水量进行了计算,并从时空两个尺度揭示了黄... 详细信息

以保护和恢复流域坡高地生态系统为目的,对坡高地最小生态需水问题进行研究,提出了坡高地生态需水和生态缺水的计算方法。以黄河流域为实例,在GIS和遥感技术支持下对坡高地最小生态需水量和缺水量进行了计算,并从时空两个尺度揭示了黄河流域坡高地生态系统最小生态需水的变化规律,研究成果可为流域生态环境建设和水资源合理配置提供依据。

关键词：生态需水坡高地系统时空变化黄河流域

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Performance Analysis for Multimedia Communication Systems with a Multilayer Queuing Network Model

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China Communications 2018年第8期15卷 67-76页

作者： Xuehua Tang Zhongyuan Wang Xiaojun Li Zhen Han Zheng He Youming Fu School of remote sensing and Information Engineering Wuhan UniversityWuhan 430079China Research institute of Wuhan University in Shenzhen Shenzhen 518000China School of Computer Science Wuhan UniversityWuhan 430072China state Grid Economic and Technological Research institute CO. LTDBeijing 102209China

Software performance evaluation in multimedia communication systems is typically formulated into a multi-layered client-server queuing network(MLCSQN) problem. However, the existing analytical methods to MLCSQN model cannot provide satisfactory solution in terms of accuracy, convergence and consideration of interlocking effects. To this end, this paper proposes a heuristic solving method for MLCSQN model to boost the performance prediction of distributed multimedia software systems. The core concept of this method is referred to as the basic model, which can be further decomposed into two sub-models: client sub-model and server sub-model. The client sub-model calculates think time for server sub-model, and the server sub-model calculates waiting time for client sub-model. Using a breadthfirst traversal from leaf nodes to the root node and vice versa, the basic model is then adapted to MLCSQN, with net sub-models iteratively resolved. Similarly, the interlocking problem is effectively addressed with the help of the basic model. This analytical solver enjoys advantages of fast convergence, independence on specific average value analysis(MVA) methods and eliminating interlocking *** experimental results on accuracy and computation efficiency verify its superiority over anchors.

关键词： multimedia communication system queuing network performance evaluation

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Spatial distribution analysis of landslides triggered by 2.08.5.12.Wenchuan Earthquake,China

Spatial distribution analysis of landslides triggered by 200...

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中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Shengwen Qi~(a,b,*),Qiang Xu~b,Hengxing Lan~c,Bing Zhang~d,Jianyou Liu~(a,1) a key Lab.of Engineering Geomechanics,institute of Geology and Geophysics,{2. {2. of sciences,beijing,China,P.O.Box 982.,Chaoyang area,beijing,10002.,China b state key Lab.of Geo-hazard Prevention and Geo-environment Protection,Chengdu University of Technology,Chengdu,610059,China c state key laboratory of Resources and Environmental System,institute of Geographic sciences and Natural Resources Research,{2. {2. of sciences,beijing,100101,China d Centre for Earth Observation and Digital Earth,{2. {2. of sciences,beijing,100190,China

The 2.08.5.12.Wenchuan Earthquake(seismic magnitude M 7.9 according to the USGS)triggered a great number of landslides.A spatial database of landslides is built by interpreting the remote sensing(RS)data which covers 11 counties severely damaged by the earthquake with area of about 31,686.12.*** geological settings of the study area are detailed mapped including geologic structure and *** digital elevation model(DEM)of the study area with resolution of 30 m×30 m is presented to address the topographic *** between the occurrence of landslides with geological settings i.e. active faults(the coseismic surface ruptures),geological unit,slope gradient,slope elevation as well as slope aspect are analyzed using spatial modeling in GIS with the aids of field *** can be concluded that the distance to the causative faults and slope gradient are much more important than other factors. Landslides are clustered distributed along the causative faults of F2.and F3,and landslides incidence are dramatically decreasing with the increasing of the distance to the causative *** landslides incidence has an obvious increase near the active faults *** concentration(LC,landslides/km)has an obvious exponent increase with slope ***,LC has no obvious relationship with geological unit and slope elevation;the difference of LC value in each geological unit(each slope elevation category)maybe have been the result affected by slope gradient for each geological unit(each slope elevation category)and distance of each geological unit(each slope elevation category)to causative fault *** map reflects the incidence of landslides in some degree,and LC increases dramatically with Intensity increasing, almost all landslides occurred in the region aboveⅥdegree. Statistics result also indicates that in the near field of causative faults,landslides tend to have the initial sliding direction similar to the movement

关键词： 2.08.5.12.Wenchuan Earthquake Slope Landslide Spatial analysis

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