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Habitat specialization and phylogenetic structure of tree species in a coastal Brazilian white-sand forest

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Journal of Plant Ecology 2014年第2期7卷 134-144页

作者： Alexandre A.de Oliveira Alberto Vicentini Jerome chave Camila de T.Castanho Stuart J.Davies Adriana M.Z.Martini Renato A.F.Lima Ricardo R.Ribeiro Amaia Iribar Vinicius C.Souza Instituto de Biociências Universidade de São PauloRua do Matão321Travessa 14São PauloSP 0550890Brazil Instituto Nacional de Pesquisas da Amazônia Av.AndréAraújo2936CP 478.ManausAM 69060001Brazil Evolution et DiversitéBiologique Bâtiment 4R1 UniversitéPaul Sabatier118 route de Narbonne31062 ToulouseFrance Smithsonian Tropical Research Institute PO Box 37012WashingtonDC 20013-7012USA ESALQ Universidade de São Paulo.Avenida Pádua Dias11PiracicabaSP 13418900Brazil

Aims The coastal Brazilian rainforest on white-sand(restinga)ranks among the most fragmented forest types in the tropics,owing to both the patchy distribution of sandy soils and widespread coastal development *** we study the environmental and evolutionary determinants of a forest tree assemblage at a single restinga forest in Southeastern *** also explore the ability of competing hypotheses to explain the maintenance of species diversity in this forest type,which includes contrasting extremes of edaphic conditions associated with flooding *** The study was conducted in a white-sand forest permanent plot of 10.24 ha on the coastal plain of Southeastern *** plot was divided into 256 quadrats of 20×20 m,which were classified into two main edaphic habitats(flooded and drained).Trees with a diameter≥1 cm at breast height were *** assembled DNA sequence data for each of the 116 morphospecies recognized using two chloroplast markers(rbcL and matK).A phylogenetic tree was obtained using the maximum likelihood method,and a phylogenetic distance matrix was produced from an ultrametric *** analyzed similarity in floristic composition and structure between habitats and related them to cross-plot distances using permutation *** model torus shift simulations were performed to obtain a statistical significance level for habitat association for each *** phylogenetic structure for the two habitats and for each 20×20 m quadrat was calculated using the mean phylogenetic distance weighted by species abundance and checked for significance using the standardized effect size generated by 5000 randomizations of phylogenetic tip *** Findings Our results indicate that partitioning among edaphic habitats is important for explaining species distributions and coexistence in restinga *** distributions within the plot were found to be non-random:there was greater floristic similarity within than betwe

关键词： habitat association torus-translation test phylogenetic community structure niche partitioning edaphic condition

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极少主义和力量的语言

世界美术 1991年第2期 2-7页

作者： Anna C.chave 封一函

1989年春,纽约现代艺术博物馆展出了唐纳德·贾德的作品——一只闪闪发光的铜箱子。当时笔者曾见到有两位十几岁的少女走上前去,边笑边用脚踢着箱子。突然,她们发现箱子的表面光亮鉴人,便对着“镜子”整理起头发来,最后她们又弯着身子... 详细信息

1989年春,纽约现代艺术博物馆展出了唐纳德·贾德的作品——一只闪闪发光的铜箱子。当时笔者曾见到有两位十几岁的少女走上前去,边笑边用脚踢着箱子。突然,她们发现箱子的表面光亮鉴人,便对着“镜子”整理起头发来,最后她们又弯着身子亲吻一下自己的形象。为什么这件作品会同时遭来脚踢和亲吻,为何博物馆人员对此无动于衷呢?这正是本文要探讨的问题。我认为,这件物体的外表所具有的作者所说的那种绝对的和“

关键词：极少主义唐纳德贾德斯特拉虚无主义者米切尔美国黑人玛利亚从一纳粹党

东太平洋Juan de Fuca板块的磁变研究

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地球物理学报 1990年第5期33卷 521-529页

作者：赵国泽行武毅浜野洋三歌田久司濑川尔朗 J.H.Filloux L.K.Law T.White A.D.chave P.Tarits 国家地震局地质研究所东京大学地震研究所东京大学海洋研究所 Scripps Institution of Oceanography Univ.of California San Diago La Jolla CA U.S.A Pacific Geoscience Centre Geological Survey of Canada Sidney BC Canada. Flinders University Bedford Park S.A.Australia. AT&T Bell Laboratories Murray HillN J.U.S.A. Institute de Physique de Globe Paris France.

作为EMSLAB电磁感应国际合作计划的一部分,通过对海底观测的三分量变化地磁场的分析,构制了横跨Juan de Fuca洋脊、Juan de Fuca板块到板块俯冲带的三条地磁转换函数剖面,计算了各个测点的地磁场感应矢量。结果表明,Juan de Fuca板块的... 详细信息

作为EMSLAB电磁感应国际合作计划的一部分,通过对海底观测的三分量变化地磁场的分析,构制了横跨Juan de Fuca洋脊、Juan de Fuca板块到板块俯冲带的三条地磁转换函数剖面,计算了各个测点的地磁场感应矢量。结果表明,Juan de Fuca板块的东、西两部分的浅部电性结构是有差异的,近海岸线的东区更导电;而深部电性结构是相对均匀的。这一结果与由大地电磁资料计算得到的二维模型剖面是一致的。

关键词：板块太平洋地磁场感应矢量磁变

肝脏脂肪浸润:应用临床MR系统的双相T1梯度回波进行检测和分级

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世界核心医学期刊文摘（胃肠病学分册） 2006年第6期2卷 23-24页

作者： Pilleul F. chave G. Dumortier J. 成虹(译) 郑世成(校) Service de Radiologie Digestive Hopital Edouard Herriot Place d'Arsonval 69003 Lyon 不详

Aim-To evaluate the relationship between histopathology results and magnetic resonance imaging (MRI) on in-and opposed-phase sequences grading of fat deposition within human liver. Materials and methods-In-and opposed-phase T1-weighted gradient-echo sequences (double echo time 2.3 ms and 4.6ms)were performed in 25 patients,using a 1.5-T clinical MR imaging system. Fat/water ratio on in-and opposed-phase images of the liver was compared with pathologically defined degree or steatosis. The signal intensity in the images was acquired with operator-defined regions of interest at the same location in both fat and water images and the ratio was calculated by dividing signal intensity of liver in opposed phased sequence on signal intensity of liver in phased sequence. Fat/water ratio and the degree of steatosis were compared using linear regression. The sensitivity and specificity of opposed-phase for diagnosing steatosis were defined by ROC analysis. Furthermore, a correlation between visual signal intensity variation (SIV)and the degree of steatosis was assessed using Pearson correlation coefficient. Results-Histology demonstrated fatty liver infiltrations in 81 %of specimens. The percentage of fatty hepatocytes was 28 +/-30 %. Fat/water ratio was significantly correlated with the pathologic grading of steatosis (r = 0.816, P < 0.001). The opposed phase MR imaging sensibility and specificity for the diagnosis of hepatic steatosis were respectively 80%and 71%. We obtained a statistically significant correlation between visual SIV and fatty liver grading (P = 0.017). Conclusion-We demonstrated a significant correlation between fat/water ratio and histological findings for the detection and grading of fatty liver.

关键词：肝脏脂肪浸润梯度回波序列 MR系统应用临床双相检测肝脏脂肪变性组织病理学成像系统

Estimating Aboveground Carbon Dynamic of China Using Optical and Microwave Remote-Sensing Datasets from 2013 to 2019

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Journal of Remote Sensing

Journal of Remote Sensing 2023年第1期3卷 19-34页

作者： Zhongbing Chang Lei Fan Jean-Pierre Wigneron Ying-Ping Wang Philippe Ciais Jérôme chave Rasmus Fensholt Jing MChen Wenping Yuan Weimin Ju Xin Li Fei Jiang Mousong Wu Xiuzhi Chen Yuanwei Qin Frédéric Frappart Xiaojun Li Mengjia Wang Xiangzhuo Liu Xuli Tang Sanaa Hobeichi Mengxiao Yu Mingguo Ma Jianguang Wen Qing Xiao Weiyu Shi Dexin Liu Junhua Yan Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China University of Chinese Academy of Sciences Beijing 100049China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China INRAE UMR1391 ISPAUniversite de BordeauxF-33140 Villenave d’OrnonFrance CSIRO Oceans and Atmosphere AspendaleVIC 3195Australia Laboratoire des Sciences du Climat et de l’Environnement CEA/CNRS/UVSQ/Universite Paris SaclayGif-sur-YvetteFrance Laboratoire Evolution et Diversite Biologique Universite Paul SabatierToulouseFrance Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark Department of Geography and Program in Planning University of TorontoTorontoON M5S 3G3Canada College of Geographical Science Fujian Normal UniversityFuzhou 3500007FujianChina School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082GuangdongChina Southern Marine Science and Engineering Guangdong Laboratory Zhuhai 519000GuangdongChina Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology International Institute for Earth System ScienceNanjing UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Department of Microbiology and Plant Biology Center for Spatial AnalysisUniversity of OklahomaNormanOKUSA LEGOS Universite de ToulouseCNESCNRSIRDUPS-14 avenue Edouard Belin31400 ToulouseFrance State Key Laboratory of Remote Sensing Science Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Climate Change Research Centre University of N

Over the past 2 to 3 decades,Chinese forests are estimated to act as a large carbon sink,yet the magnitude and spatial patterns of this sink differ considerably among *** 3 microwave(L-and X-band vegetation optical depth[VOD])and 3 optical(normalized difference vegetation index,leaf area index,and tree cover)remote-sensing vegetation products,this study compared the estimated live woody aboveground biomass carbon(AGC)dynamics over China between 2013 and *** results showed that tree cover has the highest spatial consistency with 3 published AGC maps(mean correlation value R=0.84),followed by L-VOD(R=0.83),which outperform the other *** AGC estimation model was proposed to combine all indices to estimate the annual AGC dynamics in China during 2013 to *** performance of the AGC estimation model was good(root mean square error=0.05 Pg C and R^(2)=0.90 with a mean relative uncertainty of 9.8% at pixel scale[0.25°]).Results of the AGC estimation model showed that carbon uptake by the forests in China was about+0.17 Pg C year^(-1) from 2013 to *** the regional level,provinces in southwest China including Guizhou(+22.35 Tg C year^(-1)),Sichuan(+14.49 Tg C year^(-1)),and Hunan(+11.42 Tg C year^(-1))provinces had the highest carbon sink rates during 2013 to *** of the carbon-sink regions have been afforested recently,implying that afforestation and ecological engineering projects have been effective means for carbon sequestration in these regions.

关键词： estimation Remote microwave

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电磁感应研究(一)

国外地质勘探技术 1989年第6期 25-29页

作者： Alan D.chave John R.Booker. 陈天平靳职理

数据采集和仪器近年来 EM 数据采集的改进在很大程度上来自较复杂的时间序列分析方法,而不是仪器的改进。传感器本身的进展有所加快.美国的研究小组普遍感到,SQUID(超导量子器件)大地电磁仪在野外不具备在实验室那么大的潜力,而倾向于... 详细信息

数据采集和仪器近年来 EM 数据采集的改进在很大程度上来自较复杂的时间序列分析方法,而不是仪器的改进。传感器本身的进展有所加快.美国的研究小组普遍感到,SQUID(超导量子器件)大地电磁仪在野外不具备在实验室那么大的潜力,而倾向于把感应线圈重新用到宽频带 MT 工作中.随着放大器技术的提高,对线圈要求越来越轻,

关键词：电磁感应电磁法

东太平洋Juan de Fuca板块的大地电磁研究

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地震地质 1990年第2期12卷 159-167页

作者：赵国泽行武毅浜野洋三歌田久司濑川尔朗 J.H.Filloux L.K.Law T.White A.D.chave P.Tarits 国家地震局地质研究所日本东京大学地震研究所日本东京大学海洋研究所美国加理福尼亚大学斯河利浦海洋研究所加拿大地质调查所澳大利亚弗林德斯大学美国AT和T贝尔实验室法国地球物理研究所

本研究做为电磁感应国际合作研究项目—EMSLAB计划的一部分,主要目的在于确定东太平洋年轻的海洋板块——Juan de Fuca板块及其周围地区岩石圈和软流圈的电性结构。在对海底观测的大地电磁资料定性和定量分析的基础上,进行了二维数学... 详细信息

本研究做为电磁感应国际合作研究项目—EMSLAB计划的一部分,主要目的在于确定东太平洋年轻的海洋板块——Juan de Fuca板块及其周围地区岩石圈和软流圈的电性结构。在对海底观测的大地电磁资料定性和定量分析的基础上,进行了二维数学模拟。在二维模型中,海洋地形和已知的表层构造被确定。通过改变模型的重要参数,评价响应函数和观测资料之间偏差的增加,检验模型的可靠性。结果表明,Juan de Fuca板块深部存在两个导电层,一个在40km,另一个在200km左右。这里岩石圈比其它较老板块的岩石圈薄。

关键词：板块大地电磁太平洋阻抗旋转

夏威夷-2观测台为遥测仪器在海洋研究中提供了机会

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世界地震译丛 2001年第4期32卷 68-73,86页

作者： R.Butler A.D.chave F.K.Duennebier D.R.Yoerger R.Petitt D.Harris F.B.Wooding A.D.Bowen J.Bailey J.Jolly E.Hobart J.A.Hildebrand A.H.Dodeman 肖凤云米宏亮李娟中国地震局地球物理研究所中国地震局分析预报中心

引言夏威夷-2观测台位于夏威夷和加州之间5000m 深的海底(图1)。它是第一个建在海底的全球地震台网台站。远程控制信号和电源通过一根废弃电话电缆(夏威夷-2)输送到该台站。夏威夷2电缆是美国电话电信公司出于科研目的捐献给美国地震学... 详细信息

引言夏威夷-2观测台位于夏威夷和加州之间5000m 深的海底(图1)。它是第一个建在海底的全球地震台网台站。远程控制信号和电源通过一根废弃电话电缆(夏威夷-2)输送到该台站。夏威夷2电缆是美国电话电信公司出于科研目的捐献给美国地震学联合研究协会的。

关键词：全球地震台网台站遥测仪器海洋研究夏威夷-2观测台