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

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

作者： Alexandre A.de Oliveira Alberto Vicentini j.rome 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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Estimating Aboveground Carbon Dynamic of China Using Optical and Microwave remote-Sensing Datasets from 2013 to 2019

Journal of Remote Sensing

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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 j.rôme 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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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

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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 r 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

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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

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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

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生活在不平静的行星上的计划设立美国航空航天局的固体地球研究议程

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世界地震译丛 2004年第5期35卷 60-64页

作者： S.C.Solomon V.r.Baker j.Bloxham j.Booth A.Donnellan C.Elachi D.Evans E.rignot D.Burbank B.F.Chao A.chave A.Gillespie T.Herring r.jeanloz j.LaBrecque B.Minster W.C.Pitman Ⅲ M.Simons D.L.Turcotte M.L.C.Zoback 盛菊琴宁夏回族自治区地震局

现在和未来20年固体地球科学所面临的最大挑战是什么?而对美国国家航空航天局(NASA)来说,在与其他机构合作时,什么又是解决这些挑战的最好途径呢?一份《在不平静的行星上生活》的新报告,为回答这些问题提供了一份蓝图。根据这份报告,未... 详细信息

现在和未来20年固体地球科学所面临的最大挑战是什么?而对美国国家航空航天局(NASA)来说,在与其他机构合作时,什么又是解决这些挑战的最好途径呢?一份《在不平静的行星上生活》的新报告,为回答这些问题提供了一份蓝图。根据这份报告,未来5年,固体地球科学领域最优先的一次新的宇宙飞船飞行行动是发射一颗干涉测量合成孔径雷达(inSAr)卫星。在NASA的要求下,固体地球科学工作组(SESWG)为太空机构未来25年固体地球科学的最优先目标制定了一个战略。该战略提出6个挑战,它们都具有基础科学的重要性,对社会有着重要意义并且能够通过在太空进行一系列共同的科学观测而取得实质性的进展。成功应对这些挑战将有赖于在其他的NASA计划方面与许多美国联邦机构以及国际合作伙伴之间进行密切合作和协作。固体地球科学工作组提出的计划分为5个观测方面,每一方面都将面对众多的科学挑战:陆地表面的形变、高分辨率地形和地形的变化、地球磁场的变异性、地球重力场的变异性以及地球变化表面的成像光谱。该工作组的评议工作已进行了两年(2000～2002年),包括与广泛的地球物理学团体之间进行卓有成效的对话。AGU2000年秋季和2001年春季会议的代表帮助达成了广泛的共识,并设立了网站,用于给出委员会的进展报告并邀请所有感兴趣的人士反馈意见。由华盛顿卡内基研究所的Solomon任主席的固体地球科学工作组由19位代表组成,分别来自大学、研究机构、美国航空航天局和美国地质调查局。总报告可以在http://***/***上找到。

关键词：议程挑战计划战略设立未来20年优先固体地球科学行星陆地表面

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Allometric models for estimating aboveground biomass in the tropical woodlands of Ghana, West Africa

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Forest Ecosystems 2020年第3期7卷 539-561页

作者： raymond Aabeyir Stephen Adu-Bredu Wilson Agyei Agyare Michael j.C.Weir Department of Environment and resource Studies UDS-Wa CampusWaGhana WASCAL Graduate research Programme on Climate Change and Land Use KNUSTKumasiGhana Biodiversity Conservation and Ecosystem Division CSIR-Forestry Research Institute of GhanaKumasiGhana Department of Agricultural and Biosystems Engineering KNUSTKumasiGhana Department of Natural resources Faculty of Geoinformation Science and Earth Observation(ITC)University of TwenteEnschedethe Netherlands

Background: Modelling aboveground biomass(AGB) in forest and woodland ecosystems is critical for accurate estimation of carbon stocks. However, scarcity of allometric models for predicting AGB remains an issue that has not been adequately addressed in Africa. In particular, locally developed models for estimating AGB in the tropical woodlands of Ghana have received little attention. In the absence of locally developed allometric models, Ghana will continue to use Tier 1 biomass data through the application of pantropic models. Without local allometric models it is not certain how Ghana would achieve Tier 2 and 3 levels under the United Nations programme for reducing emissions from deforestation and forest degradation. The objective of this study is to develop a mixedspecies allometric model for use in estimating AGB for the tropical woodlands in Ghana. Destructive sampling was carried out on 745 trees(as part of charcoal production) for the development of allometric equations. Diameter at breast height(dbh, i.e. 1.3 m above ground level), total tree height(H) and wood density(ρ) were used as predictors for the models. Seven models were compared and the best model selected based on model efficiency,bias(%) and corrected Akaike Information Criterion. The best model was validated by comparing its results with those of the pantropic model developed by chave et al.(Glob Chang Biol 20:3177–3190, 2014) using equivalence test and conventional paired ***: The results revealed that the best model for estimating AGB in the tropical woodlands is AGB =0.0580ρ((dbh)2 H)0.999. The equivalence test showed that this model and the pantropic model developed by chave et al.(Glob Chang Biol 20:3177–3190, 2014) were equivalent within ±10% of their mean predictions(p-values r one-tailed t-tests for both lower and upper bounds at 5% significant level), while the paired t-test revealed that the mean(181.44 ± 18.25 kg) of the model predictions of the best model of this s

关键词： Charcoal Diameter at breast height Tree height Wood density Savannah woodland

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Nine amino acids determine recognition of Verticillium dahliae effector Avel by tomato immune receptor Vel.

Nine amino acids determine recognition of Verticillium dahli...

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从植物科学到农业发展——2012全国植物生物学大会

作者： j.rdi C.Boshoven Karunakaran Maruthachalam Krishna V.Subbarao Bart P.H.j.Thomma Laboratory of Phytopathology Wageningen UniversityDroevendaalsesteeg 16708 PB WageningenThe Netherlands Department of Plant Pathology University of California

Effectors are molecules secreted by plant pathogens to facilitate infection,often by suppression of plant immune *** infection on its hosts,the soil-borne vascular wilt fungus Verticillium dahliae secretes effector protein Avel(for Avirulence on Ve1 tomato 1) that is recognized by the immune receptor Vel that is present in particular tomato *** Ave1 unambiguously contributes to fungal virulence on susceptible tomato genotypes,the intrinsic function of Avel for fungal infection is not known ***,homologs of *** Ave1(VdAve1),have been identified in the bacterial pathogen Xanthomonas axonopodis *** as XacPNP,and in the fungal pathogens Fusarium oxysporwn,Colletotrichum higginsianum and Cercospora beticola,as FoAvel,chave1 and CbAve1,*** using agroinfiltration in tobacco,we found these Avel homologs are differentially recognized by *** determine the region of Avel that is recognized by Ve1,targeted deletions and domain swaps were generated, based on the alignment of differentially recognized Avel *** show that the carboxyterminus of Ave1 determines the necrosis-inducing activity in Ve1 expressing ***,Ve1-mediated immunity can be induced by a nine amino acid sequence derived from the carboxyterminus of VdAve1.

关键词： PAMP receptor hypersensitive response(Hr) Fusarium oxysporum Xanthomonas axonopodis Colletotrichum higginsianum Cercospora beticola XacPNP

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