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A measure for spatial heterogeneity of vegetation in the center of Inner Mongolia

Progress in Natural Science:Materials International 2008年第3期18卷 289-295页

作者： Baimin Songa,b, Daming Huangc,d, Renqing Wanga, Shiyomi Masae d, Fei Xua, Wei Wanga, Gaosheng Zhanga, Xianqiang Zhanga, Jian Qiaoe a College of Life Science, Shandong University, Jinan 2.0100, china b Department of Environmental Science and Engineering, Tsinghua University, beijing 100084, china c Institute of Ecology, Department of Biological Sciences and Biotechnology, Tsinghua University, beijing 100084, china d Faculty of Science, Ibaraki University, Bunkyo 2.1-1, Mito 310-85.2. Japan e Department of Chemical Engineering, Tsinghua University, beijing 100084, china College of Life Science Shandong University Jinan 250100 China Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Institute of Ecology Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Faculty of Science Ibaraki University Bunkyo 2-1-1 Mito 310-8512 Japan Department of Chemical Engineering Tsinghua University Beijing 100084 China

This study surveyed and analyzed the vegetation heterogeneity in the center of Inner Mongolia (CIM) by a new method based on the beta-binomial distribution for each kind of vegetation. As many as 190 large quadrats of 5.mm 5.mm (representing an area of 5. km 5. km) (referred to as L-quadrats hereafter) were extracted from about an area of 475.000 km2. Each L-quadrat was divided into four small quadrats (S-quadrat) of 2.5.mm 2.5.mm (equivalent to 2. km 2. km) and the frequency of occurrence of each type of vegetation was recorded in each small quadrate. The weighted average heterogeneity from all of the vegetations composing a land- scape provides a measure at landscape level to determine the spatial intricateness of landscape composition. Our results indicated that each vegetation has its own distribution pattern and the degree of heterogeneity is different from one kind of vegetation to the other. The results proved that the beta-binomial distribution can be very useful for analyzing vegetation landscapes.

关键词： Heterogeneity Beta-binomial distribution Frequency Occurrence Inner Mongolia

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PLS path model building:A multivariate approach to land price studies-A case study in beijing

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Progress in Natural Science:Materials International 2009年第11期19卷 1643-1649页

作者： Wenjie Wu~(a,b),Wenzhong Zhang~(a,*) a Institute of Geographic Sciences and Natural Resources Research,CAS,beijing 100101,china b Graduate University of Chinese Academy of Sciences,beijing 100049,china Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel ***,the conventional statistical methods used in land analysis have some limitations,especially in cases of limited observational *** this paper,with the help of geographic {2. system(GIS) techniques,a partial least squares(PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of beijing in *** a preliminary analysis,four latent variables are selected:accessibility of the workplace {5.,livability,traffic,and environment *** results show that the observation variables have a strong explanatory power for their corresponding latent variables,and the four latent variables have varying impacts on residential land *** the latent variables,accessibility to the workplace {5. has the strongest impact on the residential land price.

关键词： land PLS path model GIS beijing

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Variation of Electromagnetic Tornogram Before and After Earthquakes

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Earthquake Research in china 1998年第2期12卷 70-76页

作者： Sun Cichang,Wang Xusheng,Liu Qingfang,Tao Yulu,Yu Ping,and Feng RuiInstitute of Geophysics,SSB,beijing 100081,china Department of Geophysics,Peking University,beijing 100871,china Seismnlogical Bureau of Hunan Province,Changsha 410001,china {5. for Seismological Data and information,SSB,beijing 100045.china

Cross-well electromagnetic tomography has been used to monitor the changes of the abso rption coefficient of electromagnetic waves before and after earthquakes for 5.years at Dahuichang fault since *** has been found that 3 months before the occurrence of moderately strong earthquakes(ML≥4.0,△2.0 km),several special changes in tomogram appeared as follows:The mean-value of the absorption coefficient dropped about 10% compared with the annually decreasing tendency; the mean difference of pixels suddenly decreased or increased in different directions; and the entropy of the paragenic matrix in a tomogram decreased and the number of low absorption pixels *** is inferred that such changes in electromagnetic tomograms are attributed to the variation of micro-cracks and porosity in *** tomography can be studied as a new technique to detect earthquake precursors.

关键词： Electromagnetic tomogram Dahuichang fault Earthquake precursor Imageanalysis.

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Sustainable Management of Planted Forests in china: Comprehensive Evaluation, Development Recommendation and Action Framework

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Chinese Forestry Science and Technology 2008年第3期7卷 1-15页

作者： HE Youjun1 LI Zhiyong1 CHEN Jie1 LIU Yong1 LIU Daoping2.WU Shengfu3 QIN Yongsheng4 XU Zhijiang5.. Research Institute of Forestry Policy and information, Chinese Academy of Forestry(CAF), beijing 100091, P. R.{2. 2. Quality Management Office and Department of Afforestation and Silviculture, State Forestry Administration(SFA), beijing 100714, P. R.{2. 3. Green Panel Consulting, beijing 100714, P. R.{2. 4. beijing Forestry and Parks Department of International Cooperation, beijing Municipal Bureau of landscape and Forestry, beijing 10002., P. R.{2. 5. International Cooperation Office, Yunnan Provincial Forestry Bureau, Kunmin 65.02., P. R.{2.

china is one of the largest countries in the world in terms of planted forests area. Planted forests play an important role in soil and water conservation, food source, timber supply and energy security, but there are still many problems waiting for immediate resolution. Based on the current development status of planted forest in china, the paper made an comprehensive analysis for the positive impact and existing problems with regard to planted forests, and then came up with policy recommendations for promoting sustainable management of planted forests, mainly including: 1) to accelerate planted forests development and improve the quality; 2. to strengthen the protection and management, and quicken the development of planted forests; 3) to enhance the scientific planning for planted forests; 4) to reinforce the management for forests harvesting so as to promote the reasonable utilization of planted forests; 5. to perfect the management system for planted forest resources and improve the managerial capacity; 6) to complete related laws and regulations and improve the policy guarantee system; 7) to reinforce the forest tenure reform and establish a sound planted forest {2. transference system. Finally, the paper presented the future action framework for guiding the sustainable management of planted forests in china.

关键词： planted forest sustainable management comprehensive evaluation development recommendation action framework

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Identification of AtENT3 as the main transporter for uridine uptake in Arabidopsis roots

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Cell Research 2006年第4期16卷 377-388页

作者： Kun Ling Chen~(1,2.*) Min Xin Xu~(2.3,*) Guang Yong Li~(2.3,*) Hui Liang~2.Zong Liang Xia~(2.3) Xin Liu~2.Ji Shu Zhang~1 Ai Min Zhang~2.Dao Wen Wang~2.~1School of Life Sciences,Northwest Agricultural and Forestry University,Yangling 712.00,china ~2.1} for Plant Gene Research({2.)and the State Kev Laboratory of Plant Cell and Chromosome Engineering,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Datun Road,Chaovang District,{2. 100101,china ~3Graduate School of the Chinese Academy of Sciences,Yuquan Road,Shijingshan District,{2. 100039,china SchoolofLifeSciences NorthwestAgriculturalandForestryUniversityYangling712100China andtheStateKeyLaboratoryofPlantCellandChromosomeEngineering InstituteofGeneticsandDevelopmen

Previous studies have shown that Arabidopsis equilibrative nucleoside transporters （AtENTs） possess transport activitieswhen produced in yeast cells and are differentially expressed in Arabidopsis ***,we report further analysis onthe nucleoside transport activities and transcriptional patterns of AtENT *** recombinant proteins of AtENTs3,6,and 7,but not those of AtENTs 1,2.4,and 8,were found to transport thymidine with high *** to previ-ous suggestion that AtENT1 may not transport uridine,this work showed that recombinant AtENT1 was a pH-dependentand high-affinity transporter of *** grown on MS plates,the AtENT3 knockout plants were more tolerant tothe cytotoxic uridine analog 5.fluorouridine than wild-type plants and the knockout plants ofAtENT 1 or ***-sistent with this observation,the AtENT3 knockout line exhibited a significantly decreased ability to take up [3H]uridinevia the roots when compared with wild-type plants and the plants with mutated AtENT 1 or *** indicates thatAtENT3,but not AtENTs 1 and 6,is the main transporter for uridine uptake in Arabidopsis *** transcription ofAtENTs 1,3,4,6,7,and 8 was regulated in a complex manner during leaf development and *** contrast,thesix AtENT members were coordinately induced during seed *** work provides new information on thetransport properties of recombinant AtENT proteins and new clues for future studies of the in vivo transport activitiesand physiological functions of the different ENT proteins in Arabidopsis plants.

关键词： Arabidopsis equilibrative nucleoside transporter expression pattern nucleoside transport functional analysis

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裂缝介质中石油运移模拟实验研究

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石油学报 2003年第4期24卷 44-47页

作者：康永尚郭黔杰朱九成陈连明曾联波石油大学石油天然气成藏机理教育部重点实验室北京102249 中国石化石油勘探开发有限公司北京100045 中国石油国际勘探开发公司北京100011 石油大学资源与信息学院北京102249

系统地介绍了裂缝介质中油水两相运移光蚀刻物理模拟实验所采用的实验模型设计方法、应考虑的因素、模型几何参数确定、拓扑结构、模型渗透率等宏观特征参数的定量化以及流体参数的选择方法。实验结果表明 :①宽缝对窄缝具有极强的流... 详细信息

系统地介绍了裂缝介质中油水两相运移光蚀刻物理模拟实验所采用的实验模型设计方法、应考虑的因素、模型几何参数确定、拓扑结构、模型渗透率等宏观特征参数的定量化以及流体参数的选择方法。实验结果表明 :①宽缝对窄缝具有极强的流动屏蔽作用 ,窄缝在油气运移中几乎不起作用 ;②在运移动力方向与渗透主方向垂直的情况下 ,当原油粘度达到一定数值时。

关键词：裂缝介质油气运移光刻模型物理实验

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人神经tau蛋白与DNA相互作用

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生物化学与生物物理进展 2004年第10期31卷 918-923页

作者：曲梅花李辉徐艳娟赫荣乔中国科学院生物物理研究所中国科学院物理研究所

通过凝胶阻滞实验表明 ,人类神经tau能够与不同来源的DNA (λDNA ,质粒DNA以及PCR产物 )相结合 ,形成tau DNA复合物 .每分子神经tau大约与长度为 6～ 10bp的核苷酸片段结合 .原子力显微镜直接证实了tau与线性质粒DNA相结合形成串珠样的... 详细信息

通过凝胶阻滞实验表明 ,人类神经tau能够与不同来源的DNA (λDNA ,质粒DNA以及PCR产物 )相结合 ,形成tau DNA复合物 .每分子神经tau大约与长度为 6～ 10bp的核苷酸片段结合 .原子力显微镜直接证实了tau与线性质粒DNA相结合形成串珠样的结构 .采用单克隆抗体Tau 1,进行免疫组织化学的实验显示 ,神经tau不但弥散地分布在SY5.细胞系的细胞质内 ,同时也存在于细胞核中 ,并形成染色致密的斑点 .以上结果提示 :神经tau在细胞核中可能参与了某种重要的生物学功能 .

关键词：人神经tau DNA 相互作用原子力显微镜(AFM)

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基于SSM/I被动微波数据的中国积雪深度遥感研究

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山地学报 2008年第1期26卷 59-64页

作者：延昊张佳华中国气象局国家气象中心中国气象科学研究院

通过对积雪和其他地物的被动微波辐射计SSM/I的微波亮温进行波谱分析,提出了一个识别积雪的SSM/I微波检测方法,与MODIS的5.合成积雪范围数据进行了比较,结果表明SSM/I的积雪范围与MODIS基本一致。对提出的SSM/I的微波积雪深度反演方法... 详细信息

通过对积雪和其他地物的被动微波辐射计SSM/I的微波亮温进行波谱分析,提出了一个识别积雪的SSM/I微波检测方法,与MODIS的5.合成积雪范围数据进行了比较,结果表明SSM/I的积雪范围与MODIS基本一致。对提出的SSM/I的微波积雪深度反演方法进行了验证,与2.06年冬季每日的中国地面积雪深度观测数据的相关系数R的平方为0.46～0.5.,偏差为-0.3～0.8cm,均方根误差rmse为4.4～6.8cm。

关键词：积雪识别积雪深度被动微波辐射计SSM/I MODIS

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西藏台错晚第四纪轮藻类的新类型

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微体古生物学报 2011年第2期28卷 145-168页

作者：刘俊英王海雷国土资源部盐湖资源与环境重点实验室北京100037 中国地质科学院盐湖与热水资源研究中心北京100037 中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所北京100037

本文的研究材料来自西藏羌塘高原西部台错古湖一个3.69 m的天然剖面,其地层测年为32.6—4.5.a。从其15.个样品中获取大量的轮藻类、介形类和腹足类及少量有孔虫等微体化石。据轮藻类藏卵器外形,顶部结构、螺旋细胞钙化式样等特征,该剖... 详细信息

本文的研究材料来自西藏羌塘高原西部台错古湖一个3.69 m的天然剖面,其地层测年为32.6—4.5.a。从其15.个样品中获取大量的轮藻类、介形类和腹足类及少量有孔虫等微体化石。据轮藻类藏卵器外形,顶部结构、螺旋细胞钙化式样等特征,该剖面的轮藻类应归属于轮藻科Characeae之轮藻属Chara。经研究得知,台错古湖在大约2. ka的时期内,曾生长过2.种轮藻,其中新类型7个,包括新种4个:Chara platea,***,***和***;新型2.:***,***;新变种1个:***。其余是曾产于国内外第四系的Chara其它分子。其中有5.新联合种:Chara alba(Madler et Staesche),***(Tang et Di),***(Tang et Di),***(Tang etDi)和***。该剖面轮藻类、介形类、腹足类等多门类微体化石的紧密共生,对轮藻植物群生态学研究具重要意义。

关键词：轮藻类新类型晚第四纪台错西藏

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Effects of Soil Matric Potential on Tomato Growth Under Drip Irrigation of Soda Alkali-saline Soils

Effects of Soil Matric Potential on Tomato Growth Under Drip...

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亚洲精细农业与计算机农业应用联合大会

作者： LIU Shuhui 1 2.KANG Yaohu 1 WAN Shuqin 1 1. Key Laboratory of Water Cycle and Related land Surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences beijing 100101 {2. 2. Graduate School of Chinese Academy of Sciences beijing 100049 {2.

The effects of irrigation frequency and soil matric potential on to mato growth under drip irrigation in No rth china were studied. Results suggested that drip irrigation frequency and soil matric potential significantly influence the distribution of soil water. By presetting threshold of soil matric potential（-5.kPa, S1;-10 kPa, S2.-15.kPa, S3;-2. kPa, S4;-2. kPa,S5. to control the timing of the irrigation cycle with vacuum tensiometers buried at 0.2. depth immediately under drip emitter. Field experiments were carried out to investigate the effect of soil matric potential on tomato growth, y ield and irrigation water use efficiency under mulch drip irrigation in Soda Alkali -saline So ils in Jilin Province in china in the year of 2.08. The results showed that the plant height, stem circu mference, LAI, Ch lorophyll content of tomato all increased with the increasing of soil matric potential. The higher the soil matric potential was, the higher the yields and the better the characteristics were. The highest yields were achieved with the soil matric potential of -5.kPa and the irrigation water use efficiency with the soil matric potential fro m -10 kPa to -15.kPa were h igher than that of other treatments.

关键词： Soda Alkali-Saline So ils Drip Irrigation So il Matric Potential Irrigation Frequency Tomato Growth

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