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distribution pattern and geochemical analysis of rare earth elements in deep-ocean sediments

Journal of Oceanology and Limnology 2021年第1期39卷 79-88页

作者： Jingxi LI Chengjun SUN Fenghua JIANG Fenglei GAO Yifan ZHENG Key Laboratory of Marine Eco-environmental Science and Technology Marine Bioresource and Environment Research CenterFirst Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory of Marine Drugs and Bioproducts Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

The content and distribution pattern of rare earth elements(REEs)in surface sediments from the Eastern and Western Pacifi c Ocean,the Northern and Southern Atlantic Ocean,and the Southwestern Indian Ocean were explored and the resources and geochemical characteristics of REEs in deep-ocean sediments from diff erent oceans were *** total REE abundances(ΣREE)in the diff erent oceans ranged as follows:Eastern Pacifi c,56.88–500.02μg/g;Western Pacifi c,290.68–439.94μg/g;Northern Atlantic,55.33–154.90μg/g;Southern Atlantic,40.83–69.30μg/g;and Southwestern Indian Ocean,20.24–64.76μg/*** corresponding LREE(La-Eu)/HREE(Gd-Lu)average values were 5.18,5.86,9.01,5.21,and 4.59,which indicated that the light REEs were all evidently enriched.δEu andδCe showed slight Eu-negative anomalies and signifi cant Ce-positive anomalies in all *** the contents of REEs in the sediments varied among the diff erent oceans,the distribution patterns of REEs were similar,and the correlation coeffi cient was greater than *** the Eastern Pacifi c sediments,ΣREE showed a signifi cantly positive correlation with Co,Cu,Zn,Mn,Mo and a weak correlation with *** the Western Pacifi c and Southern Atlantic sediments,ΣREE presented no obvious correlation and a weakly negative correlation with Co,Cu,Zn,Mn,Mo and Fe,respectively.ΣREE in the Southwestern Indian Ocean sediments positively correlated with Cu,Zn,Mn,Mo,Fe,and had a weakly negative correlation with Co.

关键词： rare earth elements(REE)geochemistry distribution pattern REE fractionation marine sediment

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Developmental Mechanism and distribution pattern of Stomatal Clusters in Begonia peltatifolia

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Acta Botanica Sinica 2002年第4期44卷 384-390页

作者：唐敏胡玉熹林金星靳晓白中国科学院植物研究所北京100093

The function of stomata in plants is controlling gas exchange and modulating water balance. The distribution pattern of stomata in most vascular plants follows a certain regulation with at least one normal epidermal cell between two stomata. However, some plants restricted in several genera of vascular plants have stomatal clusters in which more than one stoma is adjacently arranged with no epidermal cells among them. The developmental process of stomatal clusters in plants, especially in non-mutant (wild type) vascular plants, has rarely been documented, and very few studies concerning the distribution pattern of stomatal clusters on leaf epidermis have been carried out. We reported the developmental mechanism and distribution pattern of stomatal clusters in Begonia peltatifolia Li native to China. The results indicated that the clustered arrangement of meristemoids at the juvenile stage of the leaf development contributed greatly to the pattern of stomatal clusters. Additionally, satellite meristemoids derived from subsidiary cells around the mature stomata also had an impact on the development as well as the pattern of stomatal clusters. Regarding stomatal cluster and singly occurring stoma both as a stomatal unit, we found that the stomatal unit density (i.e., number of stomatal unit per area) increased gradually from the middle part to the edge and the apex of the leaf, while stomatal unit size (i.e., number of stomata per stomatal unit) decreased. The possible reason of this pattern was discussed.

关键词： Begonia peltatifolia development distribution pattern stomatal cluster

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distribution pattern of rare plants along riparian zone in Shennongjia Area

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Journal of Forestry Research 2002年第1期13卷 25-27,83页

作者：江明喜邓红兵蔡庆华中国科学院武汉植物研究所武汉430074 中国科学院沈阳应用生态研究所沈阳110016 中国科学院水生生物研究所武汉430072

Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian zone in basic study and practical management. In this study, 42 sampling belts (10 m?00 m) parallel to the bank of Xiangxi River at different elevations in Shennongjia Area were selected to investigate the riparian vegetation and rare plants. 14 species of rare plants were found distributing in riparian zone, accounting for 42.4% of the total rare plant species in Shennongjia Area. The main distribution range of the 14 rare plant species was the evergreen and deciduous mixed broadleaved forest at elevation of 1200-1800 m, where, species diversity of plant community was the maximum at the moderate elevation. The analysis of TWINSPAN divided the 14 rare species into 3 groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation species group. The analysis of DCA ordination showed similar results to that of TWINSPAN. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out that the important function of riparian zone on rare plant species protection.

关键词： Xiangxi River Rare plant Riparian zone distribution pattern Biodiversity

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Spatial distribution pattern of Populations of Isoetes sinensis Palmer, an Endangered Quillwort in China

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 694-698页

作者： WANG Jingyuan Robert Wahiti Gituru CHEN Jinming WANG Oingfeng College of Life Sciences Wuhan University Wuhan 430072Hubei China Botany Department Jomo Kenyatta University of Agriculture and Technology P. O. Box 62000-00200 Nairobi Kenya

The distribution pattern of Isoetes sinensis populations was investigated in relation to its biological characteristics such as age structure and regeneration mode, and the microenvironment. Contagious distribution pattern was found in populations of all sizes. Under the same climatic and site conditions, the heterogeneity of mieroenvironment resulting from the different depths of water and soil erosion significantly affecred the type and scale of distribution patterns of Isoetes sinensis populations. Even at the same site, the center and the edges of the water body had different effects on the distribution pattern of the plants. As one of the co-dominants, the distribution of Isoetes sinensis in communities was affected by other dominant species, especially by the evergreen grass species. Water is the major factor determining the distribution pattern of lsoetes sinensis in various communities. The pattern of contagious distribution was observed in different size of populations of ***, however the Lloyd indices obtained for the populations of various sizes differed significantly.

关键词： quillwort population distribution pattern distribution scale conservation

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distribution pattern of endangered bird species in China

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Integrative Zoology 2006年第4期1卷 162-169页

作者： Fumin LEI Hongfeng ZHAO Zuohua YIN Institute of Zoology Chinese Academy of SciencesBeijingChina College of Life Sciences Shaanxi Normal UniversityXi’anChina

In this study,we determined six“hotspots”for avian biodiversity conservation in *** analyzed the distribution patterns of 183 threatened bird species in China in conjunction with geographical data to produce a distribution map that shows the concentrations of threatened *** six biodiversity hotspots are:the western Tianshan Mountains;the Qilian and Hengduan mountains;southern Anhui,southern Jiangsu,and the Zhejiang Hills;the Songliao Plain and the northern region of the North China Plain;the island of Taiwan;and the island of *** on our analysis of a species–habitat matrix,species were determined to be distributed mainly in broadleaved forest,grassland and meadows,urban and agricultural areas,wetlands,and *** species were commonly found to have a range of three to five different habitat *** from the six biodiversity hotspots,six ecological clusters were *** strategies indicating different levels of habitat priority among the biodiversity hotspots were also recommended.

关键词： China distribution pattern endangered birds habitat species richness

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distribution pattern of Urban Housing Price Based on Multiple Big Data:A Case Study of Beijing,Shanghai,Guangzhou,and Wuhan

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Journal of Landscape Research 2021年第4期13卷 57-61,66页

作者： LIN Yichen WANG Li LIU Yating GONG Yue XU Jingyi School of Civil Engineering and Architecture Wuhan Institute of TechnologyWuhanHubei 4300732China Wuhan Jiankai General Contracting Co. Ltd.WuhanHubei 430000China

The housing price has been paid close attention by people in all walks of life,and the development of big data provides a new data environment for the study of urban housing *** price data of four national central cities (Beijing,Shanghai,Guangzhou and Wuhan) are taken as research *** the help of software GIS,exploratory spatial data analysis method is used to depict the spatial distribution pattern of urban housing price,and commonness and difference of spatial distribution of housing price are *** conclusions are as below:①regional imbalance of housing price in national central cities is significant.②Spatial distribution of urban housing price in Beijing,Shanghai,Guangzhou and Wuhan presents a polycentric pattern,and there is obvious spatial agglomeration.③The internal change of housing price in different cities has significant spatial ***,Shanghai,Guangzhou and Wuhan are taken as typical city samples for research,with reference and practical significance,which could help to effectively predict spatial development trend of housing prices in other first and second tier *** research aims to provide certain reference for the government implementing real estate control policies according to local conditions,project location and reasonable pricing of real estate developers.

关键词： Multiple big data Beijing Shanghai Guangzhou and Wuhan Urban housing price distribution pattern

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Study on distribution pattern of Plant Diversity of Forest Vegetation in Luofu Mountain,Guangdong

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Chinese Forestry Science and Technology 2007年第2期6卷 83-92页

作者： ZHENG Zhiqing CHEN Taotao School of Geographical Sciences. Guangzhou University Guangzhou 510006P R. China College of Continuing Education South China University of Technology Guangzhou 510641P. R. China

Through sample plot survey and statistic analysis,this paper adopts ecological method to study the characteristics of plant diversity of forest vegetation in Luofu Mountain,*** results show that there is a great plant diversity of forest vegetation in Luofu Mountain owing to the ascendancy of aqueous and thermal condition in subtropical *** total number of species in 4 500 m2 sample plot(s)are 170 with 3 870 individual plants in total;Dahl species richness index(D)is 44.932;Simpson diversity index(L,D)is 0.022,0.022;Simpson(1982)diversity index(D)is 3.806;Pielou evenness index(E)is 0.984 and Hulbert evenness index(E)is 0.815;Shannon-wiener diversity index(information index H')is 4.188;Asymmetry index(r)is *** indexes show that a better habitat will bring about plant diversity of forest vegetation,and the diversity of zonal vegetation shows that the higher latitude is,the less species of vegetation can be ***,vertical change of plant diversity of forest vegetation in Luofu Mountain is *** species richness index and plant diversity index show that monsoon evergreen broad-leaved forest is the tallest,mountain evergreen broad-leaved forest follows as the second and conifer-broad-leaved mixed forest is the *** Wilson β-diversity index,which is obtained by comparison between forest vegetation below 300 m and forest vegetation between 600-900 m,is *** from comparison between forest vegetation in 600-1 100 m and forest vegetation in 900-1 100 m,the Wilson β-diversity index is 0.727;by comparing forest vegetation below 300 m with forest vegetation in 900-1 100 m,the Wilson β-diversity index is *** shows that the plant diversity of forest vegetation is affected by the change in gradient of elevation.

关键词： plant diversity forest vegetation distribution pattern Luofu Mountain

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Impact of Urban Public Service Facilities on distribution pattern of Housing Price

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Journal of Landscape Research 2021年第1期13卷 81-83,88页

作者： WANG Yuqi Peking University Beijing 100871China

The impact of different public service facilities is obtained by investigating the infl uence of public service facilities on distribution pattern of housing price in 25 *** to the survey results,public education service facilities have the highest weight and the greatest impact,which also refl ects the root of“school district housing fever”from the *** sports service facilities have the lowest score when compared with other *** is not because public sports service facilities are not important,but is determined by actual situation of social development and actual living standard of residents in *** the improvement and enhancement of urban public service facilities,the construction of public service facilities should be convenient for people’s education,health,culture and entertainment.

关键词： Urban public service facilities Housing price distribution pattern Impact Questionnaire

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Study on Spatial distribution pattern of Thrip (Odentot hrips lati) on Alfalfa (Medicago sativa)

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Agricultural Science & Technology 2011年第7期12卷 990-993页

作者：赵丽丽王普昶刘玉良陈彦希贵州大学动物科学学院贵州贵阳550025 贵州省草业研究所贵州贵阳550006 内蒙古农业大学呼和浩特010019

[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip（Odentot hrips lati） on alfalfa（Medicago sativa）.[Method] Within alfalfa plantation areas,experimental plots with the sizes of 10×10,10×20,10×30,20×30,20×40,20×80,30×30,30×40,30×50,40×40,40×50,40×80 and 50×50 m2 respectively were set up in the randomly selected sampling sites of 1 m ×2 m in *** bud-emerging period and florescence period of alfalfa in the experimental plots,the number of thrips was counted and their distribution pattern was measured using XU Ru-mei＇s method.[Result] During bud-emerging period of alfalfa,the spatial distribution of thrips assumed an elliptic shape sized of 40×30-40×40 cm2 at horizontal level and that presented an ascending-falling trend of tress density down from the top at vertical *** the florescence period of alfalfa,it showed a homogeneous distribution or randomly distributed pattern at horizontal level and a falling trend of tress density from the top to the apex to the root at vertical level.[Conclusion] Our results provide theoretical basis for field selection of insect-resistant alfalfa varieties.

关键词： Thrips Different degree distribution pattern Alfalfa

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The distribution pattern of Ferns on the North-Eastern Islands of Hong Kong

The Distribution Pattern of Ferns on the North-Eastern Islan...

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第七届全国系统与进化植物学青年学术研讨会

作者： YAN Yue-Hong, Shea She SANG , XING Fu-Wu (1. South China Institute of Botany, Chinese Academy of Science, Guangzhou 2. China-Hong Kong Ecology Consultants Co., Hong Kong 3. South China Institute of Botany, Chinese Academy of Science, Guangzhou)

Field surveys on fern distribution on eight islands of north-eastern Hong Kong waters and the peninsula of north-eastern New Territories of Hong Kong were undertaken. Species composition of ferns encountered, abundance and as well as dominant plants of other vegetation groups were recorded at the surveyed transects and quadrates. Fern community pattern is described and analyzed. The

关键词： fern distribution pattern island Hong Kong

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