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生物多样性 2004年第1期12卷 206-212页

作者：王襄平王志恒方精云北京大学环境学院生态学系

基于我国的地貌特征、数字高程模型 (DEM )以及数字地形模型 (DTM)等资料 ,参考以往的研究文献 ,给出了我国主要山峰和山脉的分布图及相关的地理信息 ,为我国的宏观生态学和生物地理学研究提供基本的山地资料。

关键词：山峰山脉地貌中国分布图地理信息中国

Water status in winter wheat grown under salt stress

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Journal of Geographical sciences 2001年第2期11卷 202-208页

作者： M Larry Lopez C~1, WANG Rong~2. MAO Xue-sen~2. Takahashi Hidenori~1 (1. Hokkaido university, Graduate School of {3. {2. Science, Sapporo, 060-0810 Japan 2. Shijiazhuang Institute of Agricultural Modernization, CAS, Shijiazhuang 05002., Hokkaido university Graduate School of Environmental Earth Science Shijiazhuang Institute of Agricultural Modernization CAS

Properties of the soil surface layer, the temporal pattern of the microclimate variables as well as crop condition were combined to analyze the characteristics of the evapotranspiration from winter wheat fields in a saline soil area. In order to accomplish this analysis, evapotranspiration was divided into evaporation from the soil and transpiration from wheat. Moreover, the effect of soil salinity on evapotranspiration was evaluated through the relationship between actual evapotranspiration and potential evapotranspiration (E a /E o ) and the total soil water potential (Φ) was divided into two components: matric potential (Ψ M ) and osmotic potential (Ψ o ). Two sites with different salinity levels were chosen for this study, located in hebei Province, china. Measurements were conducted in April–May 1997 and May 1998. The Bowen ratio method was used to estimate the actual evapotranspiration (E a ), whereas potential evapotranspiration (E o ) was estimated using Penman’s equation. Measurements of soil evaporation (E s ) were obtained with micro-lysimeters, and transpiration was calculated from the difference betweenE a andE s . The results show that transpiration comprised on average almost 80% of total evapotranspiration. Evaporation from the soil differed slightly between years, but this variation was dominated by the leaf area index (LAI), which ranged from 4 to 5 during the study period of 1997 and 1998. Soil electric conductivity (EC), which is directly related to osmotic potential, ranged from 1.9 to 3.5 mS cm?1 in 1997 and was negligible in 1998. Our results indicate that lower osmotic potential decreases the total soil water potential, thus affecting plant transpiration. Hence, it is possible to say that soil salinity actually decreases evapotranspiration from winter wheat fields.

关键词： evapotranspiration potential evapotranspiration soil salinity water potential wheat

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植物酸致损伤机理与稀土调控研究

中国稀土学报 2002年第Z3期20卷 177-180页

作者：周青黄晓华江南大学生物工程学院江苏无锡214036 江南大学化学与材料工程学院

综述了酸雨对植物酸致损伤机理,在此基础上探讨了稀土调控植物代谢,减轻酸雨伤害的研究近况与存在的问题。

关键词：稀土酸雨植物伤害机理稀土调控

Synthesis and properties of nanostructured materials by DC arc and RF plasma

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Synthesis and properties of nanostructured materials by DC a...

Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion

The 9th Asia-Pacific Conference on Plasma Science and Technology and 2.st Symposium on Plasma Science for Materials

作者： Jie Zheng~1,Lei Xie,Xubo Song~1,Rong Yang~1 and Xingguo Li~(1,2.) 1 The State Key Lab.of Rare earth Mater.Chem.and Applications,college of Chemistry,{2. university,Beijing 100871,PR china 2.Advanced Materials and Nanotechnology,college of Engineering peking university,Beijing 100871,PR china

Nanostructured materials have been an important subject in research since the late *** are many methods developed for synthesis of nanoparticles such as ball-milling,precipitation,hydrothermal method,chemical vapor deposition and so on. Different from conventional methods,we have been studying synthesis of metallic, semiconductive and ceramic nanomaterials by DC arc and RF plasma methods. Recently we investigated synthesis and properties of nanostructured hydrogen storage materials and silicon oxynitrides by hydrogen plasma metal reaction(HPMR) and RF cold plasma,*** HPMR,we synthesized nanostructured Mg and Li-based hydrides and investigated their hydrogen storage *** results show that nanoparticles or hollow nanospheres can be prepared by HPMR and they have superior hydrogen absorption and desorption properties due to their small size and large specific surface *** other hand,by NH RF cold plasma,nanowires of amorphous silicon oxynitrides(a-SiON) were successfully *** results show that both the active hydrogen and nitrogen species generated in the NH plasma were essential for a-SiOxNy nanowire formation:the former one kept the activity of the catalyst while the later one ensured efficient nitrogen *** this talk,I will present our results in these areas.

关键词： Synthesis of nanomaterials DC arc plasma RF Plasma Characterization Physical and chemical properties

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Science china earth {2. 2006年第6期49卷 632-640页

作者： QIN Jun1, YAN Guangjian1, LIU Shaomin1, LIANG Shunlin2. ZHANG Hao1, WANG Jindi1 & LI Xiaowen1 1. State Key Laboratory of Remote Sensing Science, School of Geography and Remote Sensing, Research Center for RS&GIS, Beijing Normal university, Beijing 100875, china 2. Department of Geography, 2.81 Lefrak Hall, university of Maryland, college Park, MD2.742. USA 1. State Key Laboratory of Remote Sensing Science School of Geography and Remote Sensing Research Center for RS&GIS Beijing Normal University Beijing 100875 China 2. Department of Geography 2181 Lefrak Hall University of Maryland College Park MD20742 USA

The use of a priori knowledge in remote sensing inversion has great implications for ensuring the stability of inversion process and reducing uncertainties in retrieved results, especially under the condition of insufficient observations. Common optimization algorithms have difficulties in providing posterior distribution and thus cannot directly acquire uncertainties in inversion results, which is of no benefit to remote sensing application. In this article, ensemble Kalman filter (EnKF) has been introduced to retrieve surface geophysical parameters from remote sensing observations, which has the capability of not merely obtaining inversion results but also giving its posterior distribution. To show the advantage of EnKF, it is compared to standard MODIS AMBRALS algorithm and highly effi-cient global optimization method SCE-UA. The inversion abilities of kernel-driven BRDF models with different kernel combinations at several main cover types are emphatically discussed when observa-tions are deficient and a priori knowledge is introduced into inversion.

关键词： remote sensing inversion, a priori knowledge, posterior distribution, ensemble kalman filter, BRDF, kernel-driven model, albedo.

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...

福建黄岗山东南坡和西北坡乔木物种多样性及群落特征的垂直变化

2.07中国科协年会

作者： Liu Muxing~1 Wang Jingai~(2.4) Liu Lianyou~(2.3. Yan Ping~(2.3. 1.{3. of City and Environment,Huazhong Normal university,Wuhan 43.079,{2. 2.Key Laboratory of environmental Change and Natural Disaster of Ministry of Education,Beijing Normal university,Beijing 100875,{2. 3.{3. of Resources Science & Technology,Beijing Normal university,Beijing 100875,{2. 4.{3. of Geography and Remote Sensing sciences,Beijing Normal university,Beijing 100875,{2.

Ridge-furrow tillage is a kind of conservation tillage widely used for soil and water conservation in agriculture,with crop planted in ridge or *** previous researches mostly focus on the effects of ridge-furrow tillage with crop planted in ridges on crop growth and soil water content,Influence of ridge-forrow tillage with crop planted in furrows are not well documented,despite it is helpful to crop growth in arid and semiarid *** purpose of this study was evaluating the effect of ridge-furrow tillage with different surface configurations and crop planted in furrow,on the efficiency for rainwater harvesting and crop production,to determine the optimal surface configuration of ridge-furrow *** parameters of ridge heights (H) and ridge-furrow ratios (R,ratio between H and furrow width,W) were defined to determine the configuration of ridge-furrow *** field experiments,seasonal dynamic variation of volumetric soil water content, aboveground biomass and yields of oilseed rape (Brassica napus L.) were *** treatments included four kinds of ridge-furrow tillage with oilseed rape planted in furrow and one kind of conventional field tillage (CT) for *** results indicate that relative to CT,ridge-furrow tillage increased volumetric soil water content of the plow layer (0-3. cm) by 4.2.-12.1%,decreased its fluctuation in the growing season of oilseed *** the soil profile under ridge-furrow tillage,soil layer with the highest soil water content appeared in the depth of 0-3. cm,which helped oilseed rape absorb water by *** aboveground biomass,pods per plant and 1000-seed weigh under ridge-furrow tillage were larger than that under *** field comparison of oilseed rape yields under four forrow planting practices with 15,2. cm H and 1/6,1/12.1/2. R,we found the practice with 2. cm H and 1/2. R increased the efficiency of water harvesting,the growth and yield of the oilseed rape more ***,we recommend furr

关键词： ridge-furrow tillage furrow planting volumetric soil water content aboveground biomass theoretical yield rainfed agriculture

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生物多样性 2004年第1期12卷 63-74页

作者：郑成洋刘增力方精云北京大学环境学院生态学系

利用福建黄岗山东南坡 3.个样方和西北坡 13.样方的资料 ,研究该地区乔木物种丰富度的垂直变化。东南坡共记录到乔木物种 15 1种 ,隶属于 4 2. 73. ;西北坡 10 2. ,隶属于 3.0} 5 4属。两坡面的乔木树种组成相差不大。物种丰富度随... 详细信息

利用福建黄岗山东南坡 3.个样方和西北坡 13.样方的资料 ,研究该地区乔木物种丰富度的垂直变化。东南坡共记录到乔木物种 15 1种 ,隶属于 4 2. 73. ;西北坡 10 2. ,隶属于 3.0} 5 4属。两坡面的乔木树种组成相差不大。物种丰富度随海拔的变化趋势是 :随海拔升高 ,科、属、种的数量呈下降的趋势 ;东南坡科、属、种的数量在海拔 80 0 - 10 0 0m达到最大值 ,西北坡在海拔 15 0 0 - 16 0 0m达到最大值。东南坡乔木物种Shannon Wiener指数 (H′)与海拔呈负相关 ;西北坡在海拔 12.0 0 - 180 0m范围内H′高于东南坡 ;S renson指数 (IAc)在不同植被类型交替时出现上下波动 ,从常绿阔叶林向针阔混交林转化时 ,物种更替强烈 ,S renson指数明显下降。乔木物种生长特征的分析表明 ,最大树高 (Hmax)和最大胸径 (DBHmax)出现在中海拔 ,在相同海拔范围内西北坡的Hmax和DBHmax高于东南坡 ;东南坡Hmax和DBHmax的峰值出现在海拔 80 0 - 90 0m ,西北坡出现在海拔 180 0m。东南坡立木密度在海拔 15 0 0m处达最高值 ,而西北坡立木密度变化不明显 ,仅在海拔 190 0m以上明显下降。将全部乔木种划分为常绿阔叶、针叶和落叶阔叶等三种生活型 ,分析不同生活型的生长特征发现 ,常绿阔叶种类的胸高断面积和 (totalbasalarea,TBA)

关键词：乔木物种组成生物多样性海拔梯度生长特征黄岗山

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试论山地的生态特征及山地生态学的研究内容

生物多样性 2004年第1期12卷 10-19页

作者：方精云沈泽昊崔海亭北京大学环境学院生态学系

山地是一个生态复杂系统 ,它具有特定的结构和功能 ,拥有丰富的生物多样性资源、水资源、矿产资源和旅游资源。开展山地生态学研究对阐明山地系统的结构与功能、山地的生态现象与过程 ,以及合理开发利用和保护山地资源都有极为重要的意... 详细信息

山地是一个生态复杂系统 ,它具有特定的结构和功能 ,拥有丰富的生物多样性资源、水资源、矿产资源和旅游资源。开展山地生态学研究对阐明山地系统的结构与功能、山地的生态现象与过程 ,以及合理开发利用和保护山地资源都有极为重要的意义。本文在简要分析山地地形的主要要素对生态因子影响的基础上 ,对山地的生态效应进行了归纳 ,探讨了山地生态学应包含的主要研究内容。作者认为 ,在山区 ,地形地貌是形成山地结构和功能以及各种生态现象和过程的最根本因素 ,它通过改变地表的光、热、水、土、肥等生态因子而发生作用。因此 ,山地生态学应把地形地貌与各种生态现象和过程的相互作用作为其核心的研究内容。作者提出 ,山地生态学研究主要包括 :山地生态复杂性与生物多样性、山地气候变化、山地生态工程、山区可持续发展综合研究以及山地生态学研究技术与方法论等内容。

关键词：山地地形要素生态效应生物多样性自然资源山地生态学

Real-time Detection of Airborne Influenza A Viruses Using Silicon Nanowire Field Effect Transistor

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Real-time Detection of Airborne Influenza A Viruses Using Si...

河北小五台山北坡植物物种多样性的垂直梯度变化

第七届亚洲气溶胶会议

作者： Fangxia Shen1 Miaomiao Tan1 Zhenxing Wang2.Maosheng Yao1 * Zhenqiang Xu1 Yan Wu1 Jindong Wang2.Xuefeng Guo2.* and Tong Zhu1 1 State Key Joint Laboratory for {3. Simulation and Pollution Control college of {3. sciences and Engineering peking university Beijing 100871 china 2.college of Chemistry and Molecular Engineering peking university Beijing 100871 china

Numerous threats from biological aerosol exposures, such as H1N1 influenza, SARS, bird flu, and bio-terrorism necessitate the development of a real-time bioaerosol sensing system, which however is a long standing challenge in the field. Here, we reported real-time detection of airborne influenza H3.2.viruses by integrating electrically addressable silicon nanowire （SiNW） sensor devices with microfluidics and a bioaerosol-to-hydrosol air sampling system. Influenza A viruses were aerosolized into exposure chamber, and collected by an automated electrostatic sampler （AES） at a sampling flow rate of 5 L/min and transported onto the SiNW sensor device via microfludic channel via a peristaltic pump at a flow rate of 0.4 L/min in a real-time manner. The electrical conductance of the SiNW device was monitored using a pre-amplifier and a lock-in amplifier. Results show that when airborne influenza H3.2.virus samples were collected and delivered to antibody-modified SiNW devices, discrete nanowire conductance changes were observed within seconds. However, the conductance levels remained relatively unchanged when indoor air or clean air samples were delivered. Quantitative polymerase chain reaction （qPCR） tests indicated that higher virus concentrations in the air samples corresponded to higher conductance levels in the SiNW devices. The sensing system here has been demonstrated to have the capability to monitor the airborne presence of influenza A viruses in a real-time manner, typically from 1 to 2.minutes. This response time scale exceeds many of those available bioaerosol sensing systems. The work here opens a new arena for real-time monitoring of biological aerosols by integrating the technologies in different disciplines, holding great promise in the combat of fighting both infectious diseases and bio-terrorism.

关键词： Influenza A H3.2.virus bioaerosol Silicon Nanowire aerosol-to-hydrosol qPCR real-time detection

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生物多样性 2004年第1期12卷 137-145页

作者：刘增力郑成洋方精云北京大学环境学院生态学系

通过野外群落调查 ,分析了小五台山北坡植物物种多样性的垂直梯度变化。结果表明 :(1)小五台山北坡的物种丰富度随海拔的升高逐渐减小 ,物种组成趋于简单 ,乔木树种渐少。α多样性指数变化较小 ,但呈现出随海拔升高先增大、后减小的趋势... 详细信息

通过野外群落调查 ,分析了小五台山北坡植物物种多样性的垂直梯度变化。结果表明 :(1)小五台山北坡的物种丰富度随海拔的升高逐渐减小 ,物种组成趋于简单 ,乔木树种渐少。α多样性指数变化较小 ,但呈现出随海拔升高先增大、后减小的趋势。 (2.) β多样性指数很好地反映了群落之间的变化。相异系数峰值出现在海拔 14 0 0 -15 0 0m处灌丛向森林的过渡带和海拔 2.6 0 0 - 2.70 0m处森林向亚高山草甸的过渡带。海拔 14 0 0 - 15 0 0m处出现的Cody指数极大值反映了灌丛群落向森林群落的变化 ,而Cody指数在海拔 2.10 0 - 2.2.0 0m的极大值反映了阔叶林和针叶林之间的过渡。 (3.作为小五台山两种最为重要的阔叶树种 ,白桦 (Betulaplatyphylla)和红桦 (Betulaal bo sinensis)沿海拔梯度出现明显的替代现象 ,随着海拔的升高 ,白桦逐渐为红桦所取代。

关键词：小五台山北坡垂直格局物种多样性植物