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Geochemical constraints from hydrothermal fluid inclusions of altered deformation zone type Au(Ag)deposits in Yunkai area, South china

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Chinese Science Bulletin 1999年第S2期44卷 230-232页

作者： WANG Zuwei~1, ZHANG Haihua~2, YAO Dongliang~2 and ZHOU Yongzhang~3 1. Department of Geography, Tianjin Normal university, Tianjin 300071, china 2. guangzhou institute of Geochemistry, Chinese Academy of Sciences, guangzhou 510640, china 3. Department of Earth Sciences, zhongshan university, guangzhou 5102.5, china eeszhou@*** Department of Geography Tianjin Normal University Tianjin 300071 China guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Department of Earth Sciences Zhongshan University Guangzhou 510275 China

THE altered deformation zone type Au (Ag) deposits share an important part from the precious metallicore deposits in the Yunkai area, South china. Their formation is a history of poly-stage evolution. Pre- liminary source strata, Calidoniam metamorphism, Indosinian-Yanshanian ductile shear deformation andassociated hydrotheraml alteration all play certain roles in the history. This note discusses the geochemical conditional of the hydrothermal fluids during mineralization. Two representative ore deposits, the Pangxidong Ag(Au) deposit and Hetai Au deposits are selectedfor this study. They are hosted in altered ductile shear zones. Wall-rock hydrothermal alteration is bothspatially and temporally associated with the development of the ductile shear system. Silicification occurred throughout the whole alteration process. There are three groups of quartz: thepredeformational quartz, the early stage hydrothermal quartz, and the late stage hydrothermal quartz asso-

关键词： precious metallic deposit fluid inclusions mineralizing fluid South china.

Changes in biodiversity and ecosystem function during the restoration of a tropical forest in south china

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Science china(Life Sciences) 2007年第2期50卷 277-284页

作者： REN Hai,LI ZhiAn,SHEN WeiJun,YU ZuoYue,PENG ShaoLin,LIAO ChongHui,DING MingMao & WU JianGuo 1 South china Botanical Garden,Chinese Academy of Sciences,guangzhou 510650,china 2.institute of ecology and evolution,zhongshan university,guangzhou 5102.5,china 3 Guangdong institute of Entomology,guangzhou 5102.5,china 4 School of Life Sciences and Global institute of Sustainability,Arizona State university,Tempe,AZ 85287,USA 1. South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China 2. institute of ecology and evolution Zhongshan University Guangzhou 510275 China 3. Guangdong institute of Entomology Guangzhou 510275 China 4. School of Life Sciences and Global institute of Sustainability Arizona State University Tempe AZ 85287 USA

Tropical forests continue to vanish rapidly,but few long-term studies have ever examined if and how the lost forests can be *** on a 45-year restoration study in south china,we found that a tropical rain forest,once completely destroyed,could not recover naturally without deliberate restoration *** identified two kinds of thresholds that must be overcome with human ameliorative measures before the ecosystem was able to *** first threshold was imposed primarily by extreme physical conditions such as exceedingly high surface temperature and impoverished soil,while the second was characterized by a critical level of biodiversity and a landscape context that accommodates dispersal and colonization *** three treatment catchments(un-restored barren land,single-species plantation,and mixed-forest stand)exhibited dramatically different changes in biodiversity and ecosystem functioning over 4 *** mixed forest,having the highest level of biodiversity and ecosystem functioning,possesses several major properties of tropical rain *** findings may have important implications for the restoration of many severely degraded or lost tropical forest ecosystems.

关键词： rainforest restoration biodiversity conservation ecosystem functioning china

Moment tensor analysis of the acoustic emission source in the rock damage process

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Progress in Natural Science:Materials International 2005年第7期15卷 609-613页

作者： YU Huaizhong, ZHU Qingyong, YIN Xiangchu and WANG Yucang ( State Key Laboratory of Earthquake Dynamics, institute of Geology, china Earthquake Administration, Beijing 100029, china State Key Laboratory of Nonlinear Mechanics, institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, china School of Mathematics and Computational Science, zhongshan university, guangzhou 5102.5, china Center for Analysis and Prediction, china Seismological Bureau, Beijing 100036, china Quakes, Department of Earth Science, university of Queensland, Brishbane, Austrialia) State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China. State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China. School of Mathematics and Computational Science Zhongshan University Guangzhou 510275 China. Center for Analysis and Prediction China Seismological Bureau Beijing 100036 China. Quakes Department of Earth Science University of Queensland Brishbane Austrialia

To further investigate the mechanism of acoustic emission (AE) in the rock fracture experiment, moment tensor analysis was carried out. The AE sources characterized by crack sizes, orientations and fracture modes, are represented by a time-dependent moment tensor. Since the waveforms recorded by AE monitors correlate to the moment tensors, we prefer to select the P wave amplitude from the full-space Green's function of homogeneous and isotropic materials to determine the six independent components of the moment tensor. The moment tensor analysis was used to investigate the AE sources recorded in the experiment, and three types of micro-cracks were found, which are tensile mode, shear mode and mixture of the tensile and shear mode. In addition, the motion of micro-cracks was decided by eigenvectors of moment tensor. Results indicate that the moment tensor analysis may be used as a measurement to reflect the damage evolution of rock specimen.

关键词： moment tensor acoustic emission rock fracture.

Coastal geomorphic evolution at the Denglou Cape, the Leizhou Peninsula

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Acta Oceanologica Sinica 2002年第4期 591-605页

作者： Wang Lirong1,Zhao Huanting1,Song Chaojing1, Yuan Jiayi2,Yu Hongbing1 1. South china Sea institute of Oceanology, Chinese Academy of Sciences, guangzhou 510301, china 2. Department of Geoscience,zhongshan university, guangzhou 5102.5,china

The Denglou Cape, southwest of the Leizhou Peninsula, is the most typical tropical coast in the continent of *** coastal geomorphic development basics of the geology and Quaternary environment change are discussed. Aerial photograph interpretation with fieldwork is applied to draw the outlines of geomorphic types. Based on the investigative data, the exogenic forces and marine organism conditions concerning tropical coast development in the area are expounded, and coastal dynamo-deposition geomorphic bodies are analysed, mainly with sea cliff-abrasion platform,barrier-lagoon system, modern beach, coral reef and mangrove tidal flat, and the general process of coastal evolution at this area, as well as coastline changes since middle Holocene transgression.

关键词：

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广州白云山风景区植被景观空间关联分析

山地学报 2003年第4期21卷 416-421页

作者：汪永华陈北光中山大学生命科学学院华南农业大学生态研究所广东广州　5102.5 广东广州　510642

本文借鉴群落生态学种间联结的概念,采用2×2列联表,通过方差检验、X2检验与联结指数对白云山风景区的植被景观各类型间的空间关联性进行了定量分析。结果表明,空间关联能有效地分析植被景观类型之间的空间关系。尽管白云山植被景观各... 详细信息

本文借鉴群落生态学种间联结的概念,采用2×2列联表,通过方差检验、X2检验与联结指数对白云山风景区的植被景观各类型间的空间关联性进行了定量分析。结果表明,空间关联能有效地分析植被景观类型之间的空间关系。尽管白云山植被景观各类型之间呈现出正关联,且它们之间的关联很松散,具有很高的独立性,但是人类活动的干扰通过建筑等方式呈现出指射状扩散,这就使得植被的发育与发展与其呈现极其显著的空间相互排斥作用。由于植被斑块破碎,相互交错,空间异质性高,景观要素或者斑块类型表现出十分复杂的空间镶嵌的分布格局。通过景观关联度分析,大体上推断出5种植被景观要素类型之间的总体空间布局关系与规律为:'果园(E)—常绿针阔混交林(B)-常绿阔叶林(C)-疏林草地(D)-常绿针叶林(A)',以及12大主要植被斑块类型之间的空间关系:'B2—B1-C1-C18-(C15)-C16-C17-C19-C7-C2-D-A1'。

关键词：植被景观空间关联白云山风景区

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富营养化水体沉积物中磷的释放及其影响因素

生态学杂志 2004年第2期23卷 98-101页

作者：韩沙沙温琰茂广州市环境保护科学研究所广州510620 中山大学环境科学系广州510275

综述了富营养化水体沉积物中磷的化学形态、释放规律及其影响因素。化学形态分为水溶性磷、铝磷、铁磷、钙磷、还原态可溶性磷、闭蓄磷、有机磷等 7种 ,其分布取决于各形态磷的性质。磷释放受 7种因素影响 ,厌氧、高 pH或低 pH值、高温... 详细信息

综述了富营养化水体沉积物中磷的化学形态、释放规律及其影响因素。化学形态分为水溶性磷、铝磷、铁磷、钙磷、还原态可溶性磷、闭蓄磷、有机磷等 7种 ,其分布取决于各形态磷的性质。磷释放受 7种因素影响 ,厌氧、高 pH或低 pH值、高温、扰动、生物活动、底泥与水体含磷量的浓度差值以及钙质沉积物组分等因素均能促进沉积物中磷的释放。

关键词：沉积物磷化学形态释放规律影响因素

Molecular phylogeny of the entomopathogenic fungi of the genus Cordyceps(Ascomycota:Clavicipitaceae) and its evolutionary implications

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Journal of Systematics and evolution 2010年第6期48卷 435-444页

作者： 1Li-Hua TIAN 1Bo HU 1Hui ZHOU 2Wei-Ming ZHANG 1Liang-Hu QU 1Yue-Qin CHEN1(Key Laboratory of Gene Engineering of the Ministry of Education,State Key Laboratory of Biocontrol,zhongshan university,guangzhou 5102.5,china) 2(Microbiology institute of Guangdong(HMIGD),guangzhou 510070,china) (Key Laboratory of Gene Engineering of the Ministry of Education State Key Laboratory of Biocontrol Zhongshan University Guangzhou 510275 China) (Microbiology institute of Guangdong (HMIGD) Guangzhou 510070 China) *Correspondence: Yue-Qin CHEN *Correspondence: Author for correspondence. E-mail: lsscyq@*** Tel.: 86-20-84112739 Fax: 86-20-84035661.

Cordyceps is an endoparasite ascomycetous genus containing approximately 450 species with a diversity of insect hosts,traditionally included in the family Clavicipitaceae of *** the relationships among species with a varied range of morphologies and hosts is of importance to our understanding of the phylogeny and co-evolution of parasites and hosts in entomopathogenic *** this end,we used a combination of molecular index and morphological characters from 40 representative species to carry out comprehensive molecular phylogenetic *** on the phylogenetic tree,we used the program DISCRETE for inferring the rates of evolution and finding ancestral states of morphological *** phylogenetic analyses revealed two important points.(i) Types of perithecia attached to stroma reflected an evolutionary trend in *** vertically immersed perithecia form was the ancestral state,superficial and obliquely immersed perithecia were derived characters,obliquely immersed was *** with obliquely immersed perithecia were in a closely related group and were the derived group.(ii) A strong correlation between fungal relatedness and the microhabitat supported the hypothesis that the host jumps through commingling in soil *** on the results of these analyses,host switching explains the diversity of entomopathogenic fungi of the genus Cordyceps.

关键词： Cordyceps entomopathogenic fungi evolutionary implication molecular phylogeny.

Evaluation of 10 plant barcodes in Bryophyta (Mosses)

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Journal of Systematics and evolution 2010年第1期48卷 36-46页

作者： 1,2 Yan LIU 3 Hai-Fei YAN 4 Tong CAO 3 Xue-Jun GE 1(institute of Applied ecology, Chinese Academy of Sciences, Shenyang 110016, china) 2(Graduate university of the Chinese Academy of Sciences, Beijing 100049, china) 3(Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South china Botanical Garden, Chinese Academy of Sciences, guangzhou 510650, china) 4(College of Life & Environment Sciences, Shanghai Normal university, Shanghai 200234, china) (institute of Applied ecology Chinese Academy of Sciences Shenyang 110016 China) (Graduate university of the Chinese Academy of Sciences Beijing 100049 China) (Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (College of Life & Environment Sciences Shanghai Normal University Shanghai 200234 China) *Correspondence: Tong CAO Xue-Jun GE *Correspondence: *?Author for correspondence: E-mail: ct1946@*** xjge@*** Tel./Fax: 86-20-3725 2551.

DNA barcoding is a molecular tool that uses a standardized DNA region to identify *** preliminary study reported here is the first attempt to specifically focus on universality and attributes of candidate barcodes across a wide systematic range of *** tested eight previously proposed plant barcoding regions(atpF-atpH, ITS2, matK, psbK-psbI, rbcL, rpoB, rpoC1, and trnH-psbA) and two popular phylogenetic markers(rps4 and trnL-trnF of cpDNA) in 49 moss species and 9 liverwort species, representing half of the orders in moss *** ITS2, rbcL, rpoC1, rps4, trnH-psbA and trnL-trnF regions showed good universality, and therefore the efficacy of these loci as DNA barcodes was further evaluated in 36 mosses and 2 liverworts, each of which included two to three individuals per *** five loci, ***, rpoC1, rps4, trnH-psbA and trnL-trnF, were easy to amplify and sequence and showed significant inter-specific genetic variability, making them potentially useful DNA barcodes for *** best performing single loci were the rbcL and rpoC1 coding *** loci showed equivalent performance and combinations of them did not greatly increase their discrimination *** addition, phylogenies generated from each of the separate regions and multi-locus combinations by using best-fit and Kimura 2-parameter models were compared, but no significant difference was found.

关键词： Bryophyta DNA barcoding rbcL rpoC1 rps4 trnH-psbA trnL-trnF.

Woodland Landscape Ecological Network Dynamic and Amelioration Analysis of zhongshan City

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Woodland Landscape Ecological Network Dynamic and Ameliorati...