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Teffichthys wui sp. nov., a new perleidid fish from the Early Triassic of Jiangsu and Anhui, China
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作者 XU Guang-Hui YUAN Zhi-Wei +3 位作者 REN Yi LIAO Jun-Ling ZHAO Li-Jun SONG Hai-Jun 《古脊椎动物学报(中英文)》 CSCD 北大核心 2024年第3期165-185,共21页
Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olen... Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olenekian,Early Triassic)marine deposits of Jurong,Jiangsu and Chaohu,Anhui,China.This new discovery documents the third and youngest species of Teffichthys,which is slightly younger than the Dienerian(Induan)T.elegans from Guizhou and the early Smithian T.madagascariensis from Madagascar.The new species shows diagnostic features of Teffichthys(presence of a spiracular,38-41 lateral line scales,and no more than three epaxial rays in the caudal fin)but differs from T.madagascariensis and T.elegans in some autapomorphies(e.g.,a horizontal opercle/subopercle contact and smooth scales with a nearly straight posterior margin).The diagnostic features for the genus Teffichthys and the family Perleididae are emended based on detailed comparisons of the new taxon with other perleidids.The phylogenetic relationships of perleidids with other stem neopterygians are discussed using a cladistic approach,and the results provide new insights into the phylogeny and classification of main stem neopterygian clades. 展开更多
关键词 Jiangsu anhui Early Triassic Perleidiformes OSTEOLOGY PHYLOGENY
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Centuries-Old Villages in Southern Anhui:Xidi and Hongcun
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作者 MENG JIAXIN 《China Today》 2024年第5期76-80,共5页
Xidi and Hongcun are two of the most representative ancient villages in the southern part of Anhui Province.Dating back to the Song Dynasty,they still preserve hundreds of residential buildings from the Ming and Qing ... Xidi and Hongcun are two of the most representative ancient villages in the southern part of Anhui Province.Dating back to the Song Dynasty,they still preserve hundreds of residential buildings from the Ming and Qing Dynasties. 展开更多
关键词 Province. anhui hundreds
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Species and Control Techniques of Main Diseases and Insect Pests of Camellia oleifera in Anhui Province
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作者 Juanjuan HU Hao SONG +5 位作者 Zhihua CAO Yulu CHEN Jie WANG Wangsheng ZHU Dewu YAO Bangxing HAN 《Plant Diseases and Pests》 CAS 2023年第3期1-4,13,共5页
[Objectives]The paper was to master the species,incidence regularity and control techniques of main diseases and insect pests of Camellia oleifera in Anhui Province.[Methods]The species of main diseases and insect pes... [Objectives]The paper was to master the species,incidence regularity and control techniques of main diseases and insect pests of Camellia oleifera in Anhui Province.[Methods]The species of main diseases and insect pests of C.oleifera in major C.oleifera afforestation bases and seedling bases in Anhui Province were investigated through field survey and literature search.Afterwards,the symptom characteristics,occurrence regularity and harms of diseases and insect pests were analyzed,and scientific and reasonable control techniques were put forward.[Results]The main diseases of C.oleifera in Anhui Province were soft rot disease,blister blight,anthracnose,sooty blotch,etc.,and the main insect pests were Euproctis pseudoconspersa,Biston marginata,Hypomeces squamosus,Curculio chinensts,Chrenoma atritarsis,etc.The control techniques mainly included ecological regulation,physical prevention and control,chemical prevention and control,and biological prevention and control.[Conclusions]The results will promote the high-quality development of C.oleifera industry in Anhui Province,and contribute to the improvement of China s edible vegetable oil supply and national grain and oil security. 展开更多
关键词 anhui Province Camellia oleifera DISEASES Insect pests Prevention and control technique
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Mitochondrial DNA Sequences Imply Anhui Musk Deer a Valid Species in Genus Moschus 被引量:13
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作者 宿兵 王应祥 王岐山 《Zoological Research》 CAS CSCD 北大核心 2001年第3期169-173,共5页
Anhui musk deer [ Moschus ( moschiferus/berezovskii ) anhuiensis ] has been a taxonomic mystery since its discovery in early 80's.In this paper,with museum samples,we sequenced the complete cytochrome b ge... Anhui musk deer [ Moschus ( moschiferus/berezovskii ) anhuiensis ] has been a taxonomic mystery since its discovery in early 80's.In this paper,with museum samples,we sequenced the complete cytochrome b gene of five Anhui musk deer.When compared with other species in Genus Moschus ,Anhui musk deer showed a rather level of sequence divergence from all the other species in this genus.The phylogenetic trees constructed by multiple methods supported the same topology,in which the monophyly of Anhui musk deer was clearly demonstrated.Therefore,our molecular data suggest a full species status for Anhui musk deer ( Moschus anhuiensis ),rather than a subspecies of either M moschiferus or M berezovskii previously suggested by morphological studies. 展开更多
关键词 Musk deer Genus Moschus anhui musk deer Cytochrome b gene Molecular phylogeny
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Risk Assessment of Hail Disaster on Cotton——A Case Study in Anhui Province 被引量:2
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作者 尹圆圆 王静爱 +2 位作者 赵金涛 岳耀杰 马进 《Agricultural Science & Technology》 CAS 2012年第8期1744-1748,共5页
[Objective] The aim was to reveal the pattern of hail disaster risk for cotton in Anhui Province. [Method] Based on database of risk evaluation on hail disaster for cotton in Anhui Province, statistical inference and ... [Objective] The aim was to reveal the pattern of hail disaster risk for cotton in Anhui Province. [Method] Based on database of risk evaluation on hail disaster for cotton in Anhui Province, statistical inference and comprehensive indices measurement were made use of for extraction of disastrous index of hail (H) and loss rate of cotton (L). Hail vulnerability curves in four stages (seedling, bud, boll and boll opening stages) of cotton were fitted by Matlab and SPSS software. Risk evaluation on hail disaster of cotton in Anhui Province was conducted and the related map was drawn on basis of yearly model of loss rate (by hail disaster), as follows: Sa=n∑i=1Si-a∏i=1Si=1-(1-Si) [Result] In Anhui Province, high risk area by hail concentrates in northeast regions and mountainous regions in west of Anhui, and lower risk area is distributed in middle and down streams of Yangtze River and mountainous area in south of Anhui. [Conclusion] The research explored evaluation methods on hail risks based on the limited information, and could provide references for risk evaluation on hail disaster in other regions. 展开更多
关键词 anhui Province Hail disaster COTTON Risk assessment
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Classification and Development Laws of Karst Landform in Suzhou Area, North Anhui Province of China
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作者 马艳平 陈松 《Journal of Landscape Research》 2011年第9期92-95,共4页
Suzhou area in north Anhui Province is a low hilly area on the Huaibei Plain where carbonate rocks and karstification are widely distributed, and karst landscapes form major physical contours of the bedrock outcrops. ... Suzhou area in north Anhui Province is a low hilly area on the Huaibei Plain where carbonate rocks and karstification are widely distributed, and karst landscapes form major physical contours of the bedrock outcrops. Through field investigation, karst landscapes of Suzhou area were divided into two categories based on their morphological characteristics: macro-geomorphologic landscapes including normal hills, dry valleys, karst springs and caves, and micro-corrosion landscapes including corrosion pits, dissolved pores, dissolution traces, corrosion cracks, clints and karrens. Distribution, development and scale of karst landscapes in this region are controlled by climate, rock type, structure, topography and other factors. It was suggested that karst landscapes in the study area could be used as a representative of karst landforms in North China. 展开更多
关键词 KARST LANDFORM CLASSIFICATION Development laws KARST in NORTH China Northern anhui Province
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Study on Tourism Development in Inferior Tourism Regions of Anhui Province
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作者 刘成 《Journal of Landscape Research》 2009年第5期84-89,共6页
This study aims to summarize the characteristics of 3 types of inferior tourism regions,so as to contribute to the local tourism development and provide references for the tourism development of other inferior tourism... This study aims to summarize the characteristics of 3 types of inferior tourism regions,so as to contribute to the local tourism development and provide references for the tourism development of other inferior tourism regions.With Anhui Province as an example,this study classifies different types of inferior tourism regions,and figures out the definite counties (cities) to assess their richness of tourism resources and regional development levels by utilizing SPSS and fully analyzing the data after calculating the economic development levels of these counties (cities).For I-class inferior tourism regions,regional cooperation model and brand management model should be adopted to improve their competitiveness,for II-class inferior tourism regions,poverty alleviation model should be adopted and moderate development strategy for III-class inferior tourism regions. 展开更多
关键词 INFERIOR TOURISM ZONE TOURISM in anhui PROVINCE TOURISM development
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Anhui Flying Tiger Automobile Group Corporation(Huaihai Machinery Factory,Anhui Province)
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《China's Foreign Trade》 1996年第8期47-47,共1页
The Anhui Flying Tiger(Feihu)Automobile Group Corporation is composedof 81 enterprises and institutions forproduction and coordination.The AnhuiHuaihai Machinery Factory—the coreenterprise—is the key national automo... The Anhui Flying Tiger(Feihu)Automobile Group Corporation is composedof 81 enterprises and institutions forproduction and coordination.The AnhuiHuaihai Machinery Factory—the coreenterprise—is the key national automobilemanufacturer.The factory has total assets ofRMB480 million,staff of 3,400,including500 medium-to-senior technical people,annual production capacity of 50,000 forautomobiles,with their quality proven to beClass A for seven years running.Since1992,the factory has been aiming at theinternational market,exporting more 展开更多
关键词 Huaihai Machinery Factory anhui Province more anhui Flying Tiger Automobile Group Corporation
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Spatio-temporal Variations of Evapotranspiration in Anhui Province Based on MOD16 Products 被引量:1
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作者 黄飞羽 何彬方 +1 位作者 汪翔 黄洋 《Agricultural Science & Technology》 CAS 2017年第11期2092-2097,2105,共7页
Based on the MOD16 remote sensing product provided by NASA, the temporal and spatial distribution characteristics of evapotranspiration in Anhui Province from 2000 to 2014 were analyzed statistically with the support ... Based on the MOD16 remote sensing product provided by NASA, the temporal and spatial distribution characteristics of evapotranspiration in Anhui Province from 2000 to 2014 were analyzed statistically with the support of ENVI remote sensing image processing system and ARCGIS .geographic information system. The results showed that: (1) The annual average ET in Anhui Province was 694.9 mm from 2000 to 2014, less than half of PET, indicating that Anhui Province as a whole was in dry climate and water shortage, particularly significant in 2011-2014, with the maximum value of 730.6 mm occurring in 2003, and the minimum value of 647.6 mm occurring in 2011. The monthly average ET and PET showed a single peak distribution pattern, ET peak appearing in August, and PET peak appearing in May. (2) Linear regression analysis of ET and PET showed that there was a signif- icant decrease trend in ET in Anhui Province from October to March of the following year, and in addition, there was also a decreasing trend in the summer from June to July, but PET for the whole year demonstrated an increasing trend. The change trends of both illustrated that drought in Anhui Province was becoming more and more serious. (3) The spatial distribution of ET and PET showed that Anhui Province had obvious characteristics of high in south and low in north, and the north had large yearly and monthly changes, while the south had relatively stable changes. (4) The evapotranspiration of different land use types showed different an- nual and monthly variation characteristics, and the overall expression of annual evapotranspiration was in the order of forest 〉 grassland 〉 farmland. In terms of the monthly change, monthly evapotranspiration was manifested as winter grassland larger than the forest, forest evapotranspiration gradually exceeding the grass, and the evapotranspiration gap among the three widening continuously until the peak appearing in July or August. Due to the seasonality of crop plantation and under the common action of temperature, precipitation and other sensitive factors, the monthly evapotranspiration of forest and grassland was of single peak distribution with the maximum appearing in July, and the monthly evapotranspiration of farmland showed double peak distribution, appearing respectively in May and August, the former being weaker than the latter in strength 展开更多
关键词 MOD16 EvapotranspiraUon Land anhui Province
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SHRIMP U-Pb Zircon Geochronology of the Xiaotongguanshan and Shatanjiao Intrusions and Its Petrological Implications in the Tongling Area, Anhui 被引量:22
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作者 DI Yongjun WU Ganguo +4 位作者 ZHANG Da SONG Biao ZANG Wenshuan ZHANG Zhongyi LI Jinwen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第6期795-802,共8页
This paper determines the crystallization ages of the Xiaotongguanshan quartz monzodiorite and Shatanjiao quartz monzonitc porphyry from the Tongling area using the SHRIMP zircon U-Pb method. The crystallization age o... This paper determines the crystallization ages of the Xiaotongguanshan quartz monzodiorite and Shatanjiao quartz monzonitc porphyry from the Tongling area using the SHRIMP zircon U-Pb method. The crystallization age of the former is 142.8±1.8 Ma; that of the latter is 151.8±2.6 Ma. These data indicate that they were formed during the Late Jurassic (142.8 to 151.8 Ma). Zoned magma chamber was formed because of double diffusive convection. Therefore, the intrusive sequence of magma is generally from quartz monzonite through quartz monzodiorite to pyroxene monzodiorite, i.e. an inverted sequence. 展开更多
关键词 ZIRCON SHRIMP zircon U-Pb age GRANITOIDS Late Jurassic Tongling area anhui
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Lower Triassic Inorganic Carbon Isotope Excursion in Chaohu, Anhui Province, China 被引量:26
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作者 Tong Jinnan Qiu Haiou Zhao Laishi Zuo Jingxun China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2002年第2期98-106,共9页
This paper reports a Lower Triassic inorganic carbon isotope profile from the North Pingdingshan Section in Chaohu, Anhui Province, China, which was situated in a deep part of the Lower Yangtze carbonate ramp. The ... This paper reports a Lower Triassic inorganic carbon isotope profile from the North Pingdingshan Section in Chaohu, Anhui Province, China, which was situated in a deep part of the Lower Yangtze carbonate ramp. The δ ( 13 C) excursion shows two periods from the Permian Triassic boundary to the lower Spathian substage, corresponding to the ecosystem undergoing evolution and recovery after the end Permian mass extinction and related events. The first period starts at the δ ( 13 C) depletion caused by the mass extinction and evolves with a gradual δ ( 13 C) increase resulting from the development of some disaster taxa during the Induan. The strong Smithian δ ( 13 C) depletion in the second period might be formed by the collapse of the disaster ecosystem and the biotic recovery occurred with the explosive increase of bioproductivity in the Spathian. Thus the δ ( 13 C) excursion in the Lower Triassic expresses patterns of biotic evolution and recovery during the erratic ecosystem that followed the great end Permian mass extinction. 展开更多
关键词 Lower Triassic inorganic carbon isotope extinction and recovery CHAOHU anhui Province.
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Underplating of Mesozoic Mantle-derived Magmas in Tongling, Anhui Province: Evidence from Megacrysts and Xenoliths 被引量:10
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作者 DUYangsong LEEHyunkoo QINXinlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期131-136,共6页
Lithological observations and mineralogical analyses on pyroxene and hornblende megacrysts and pyroxene and hornblende cumulates in xenoliths in the Mesozoic plutons of the Tongling region, Anhui Province, provide evi... Lithological observations and mineralogical analyses on pyroxene and hornblende megacrysts and pyroxene and hornblende cumulates in xenoliths in the Mesozoic plutons of the Tongling region, Anhui Province, provide evidence for the magmatic underplating of mantle-derived alkali-olivine basalt at circa 140 Ma. The pyroxene and hornblende megacrysts and cumulates were formed through the AFC process at depths ranging from 27 to 35 km. 展开更多
关键词 magma underplating MEGACRYSTS XENOLITHS Tongling in anhui Province
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Multifractal Analysis of Element Distribution in Skarn-type Deposits in the Shizishan Orefield,Tongling Area,Anhui Province,China 被引量:8
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作者 WANG Qingfei DENG Jun +5 位作者 WAN Li ZHAO Jie GONG Qingjie YANG Liqiang ZHOU Lei ZHANG Zhijun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期896-905,共10页
A series of element concentrations sampled from four drill cores with a length about 1000 m into different skarn-type deposits were selected from the Shizishan orefield, central Tongling, southeastern part of Anhui Pr... A series of element concentrations sampled from four drill cores with a length about 1000 m into different skarn-type deposits were selected from the Shizishan orefield, central Tongling, southeastern part of Anhui Province. Using the multifractal method, the distribution and migration characteristics of the major and trace elements are analyzed. The multifractal spectrum of the major elements is left-skewed, whereas the spectrum of the trace elements is right-skewed, which shows that in the process of skarn formation, the trace elements were enriched only locally, and major elements transported within a much larger range. The correlation coefficients of the multifractal parameters Aa (width of the multifractal spectrum) of the four drill cores are relatively low, but the correlation coefficients of the multifractal parameters R (spectrum symmetry parameter) and Af are relatively higher, indicating that although the non-homogeneous intensity of the distribution of elements is inconsistent, their spatial accumulation patterns are almost the same during the ore-forming process. The statistics of the mnltifractal parameters of various elements in the different locations show that the ore-forming processes and element migration pattern in the Shizishan orefield are consistent, and that the migrations of trace elements and major elements exhibit some differences. 展开更多
关键词 metallogenic elements SKARN multifractal spectrum TONGLING anhui China
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Geochemistry of Rare Earth Elements in Xikeng Ag-Pb-Zn Ore Deposit, South Anhui, China 被引量:7
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作者 陈天虎 杨学明 +2 位作者 岳书仓 李双应 王道轩 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第3期169-173,共5页
In this paper, a comparative study is done on the geochemical charateristics of REE in ore, ore-hosted rocks of Lantian group, granite related to ore deposit, and altered rocks for tracing origin of ore-forming materi... In this paper, a comparative study is done on the geochemical charateristics of REE in ore, ore-hosted rocks of Lantian group, granite related to ore deposit, and altered rocks for tracing origin of ore-forming materials. The result indicates that the ore-forming fluid and ore-forming materials for Xikeng silver-polymetallic ore deposit were derived from Yixian granite's magmatic activity. Water-rock reaction of the hydrothermal fluid with the carbonate-rich stratum led the altered rock to relatively enrich in HREE. 展开更多
关键词 rare earths GEOCHEMISTRY silver-polymetallic ore deposit South anhui
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A New Species of the Genus Protobothrops(Squamata:Viperidae:Crotalinae) from the Dabie Mountains,Anhui,China 被引量:8
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作者 Xin HUANG Tao PAN +5 位作者 Demin HAN Liang ZHANG Yinxu HOU Lei YU Heming ZHENG Baowei ZHANG 《Asian Herpetological Research》 SCIE 2012年第3期213-218,共6页
During a biological survey in July 2011, a pit viper was collected from the Yaoluoping Nature Reserve in the Dabie Mountains, Anhui, China. The pit viper’s the total length measured 836 mm with a dorsal ground color ... During a biological survey in July 2011, a pit viper was collected from the Yaoluoping Nature Reserve in the Dabie Mountains, Anhui, China. The pit viper’s the total length measured 836 mm with a dorsal ground color of yellowbrown, decorated by 56 dark-brown transverse bands. The 4thsupralabial squama of the new species is separated from subocular by two squamae, and the tip of tail is orange; this combination of characters distinguish it from other species of the genus Protobothrops. Based on the body proportions, number of squamae, body color pattern, and comparing the data of its life history with those of other species of Protobothrops, we herein describe it as a new species, belonging to the genus of Protobothrops. 展开更多
关键词 taxonomy Protobothrops dabieshanensis sp.nov. SNAKE Yaoluoping Nature Reserve anhui
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Discussion on Induan-Olenekian Boundary in Chaohu, Anhui Province, China 被引量:7
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作者 Zhao Laishi Tong Jinnan Zuo Jingxun Ming Houli China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2002年第2期141-150,共10页
This paper proposes a scheme for the definition of the Lower Triassic Induan Olenekian boundary (IOB) based on investigation of sections in Chaohu, Anhui Province, China as well as data accumulated from other studies... This paper proposes a scheme for the definition of the Lower Triassic Induan Olenekian boundary (IOB) based on investigation of sections in Chaohu, Anhui Province, China as well as data accumulated from other studies elsewhere. The conodont Neospathodus waageni is suggested as the index fossil of the boundary. According to the FAD of N. waageni , the IOB is at the base of bed 25 2 of the West Pingdingshan Section in Chaohu, 42.19 m above the Permian Triassic boundary, and it is slightly higher than the base of the Flemingites Euflemingites Ammonoid Zone at the section. 展开更多
关键词 Lower Triassic Induan Olenekian boundary conodont biostratigraphy CHAOHU anhui Province.
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Geochemical Characteristics of Sedimentary Manganese Deposit of Guichi, Anhui Province, China 被引量:5
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作者 谢建成 杨晓勇 +1 位作者 杜建国 许卫 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期374-380,共7页
The sedimentary manganese deposits occurring in Gufeng formation of the Permian in Guichi area, south Anhui Province, include manganese carbonate deposit formed by sedimentation, and manganese oxide deposit made by la... The sedimentary manganese deposits occurring in Gufeng formation of the Permian in Guichi area, south Anhui Province, include manganese carbonate deposit formed by sedimentation, and manganese oxide deposit made by later oxidation. The total REE contents of these samples are relatively low ( 〈 250 × 10^- 6), belonging to LREE-enriched type, showing LREE enrichment during the process of formation of Mn deposit, especially during Mn-oxidizing process. Three normalized REE patterns and SCNA-normalized trace elements spider diagrams of the Mn-bearing sequence rocks and ores in this area reflect their same origin of ore sources, which is similar to rock-forming and ore-forming conditions. The Mnforming materials primarily came from the continent with higher mature degree and single material source. The δEu and δCe negative anomaly and Ce anomaly ( 〈 - 0.1) manifest that Mn-bearing sequence of the Permian was mostly formed in marine basin and oxidative environment. The Sr and Ba anomaly, Sr/Ba and Co/Ni values reflect the Mn deposit environment was of deep water and high-salinity of marine facies. Although the Ce/La (mean 1.05), Y/Ho (25 - 41.5) and trace metals show a variety of correlations with Mn in the ten rock samples, which show multiple sources for the manganese, the analysis of geochemical characteristics indicate that the material sources of Mn deposit have been primarily terrestriallyderived. Another source of the manganese probably comes from the seafloor volcanism in this area. Analysis of sedimentary features and geohistoric evolvement reveals that the maximum transgression of the Qixia Period, ore district is then in deep shelf-basin sedimentary setting and the Mn-bearing sequence is deposited. 展开更多
关键词 manganese ore trace elements GEOCHEMISTRY Guichi area anhui Province rare earths
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A New Idea of Sinian Doushantuo'an Metaphyte Fossils from Xiuning, Anhui Province 被引量:5
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作者 Tang Feng, National Geological Museum of China, Xisi, Beijing 100034Yin Chongyu and Gao LinzhiInstitute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang, Beijing 100037 Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第4期491-501,515-517,共14页
This paper gives a summary of the fossil data from the Sinian Doushantuo' an Lantian Formation in the Xiuning area, Anhui Province, China, and reports the genital butt structure comparable to that of some modern a... This paper gives a summary of the fossil data from the Sinian Doushantuo' an Lantian Formation in the Xiuning area, Anhui Province, China, and reports the genital butt structure comparable to that of some modern advanced algae and the fossil structure comparable to the dehiscence of sporangia as well as the ontogenetic phenomenon occurring possibly from the formation of embryos by zygote germination to the production of sessile benthonic algal adults. This phenomenon furnishes a useful clue to the further study of the life history of alternate generations in advanced algae and provides megafossil evidence for the sex differentiation of metaphytic algae. 展开更多
关键词 Doushantuo' an stage metaphyte fossil reproductive structure alternation of generations Xiuning anhui
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Study of the Emplacement Mechanism of the Fenghuangshan Granite Pluton and Related Cu-Au Mineralization in Tongling, Anhui Province 被引量:4
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作者 WUGanguo ZHANGDa LIDongxu ZHANGXiangxin SHAOYongjun ZANGWenshuan WANGQunfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期492-502,共11页
The Fenghuangshan Pluton is located in the Tongling polymineral-cluster district in the middle-lower section of the Yangtze metallogenic belt. In tectonic terms, it is in the middle of the Guichi-Fanchang faulted fold... The Fenghuangshan Pluton is located in the Tongling polymineral-cluster district in the middle-lower section of the Yangtze metallogenic belt. In tectonic terms, it is in the middle of the Guichi-Fanchang faulted fold bundle of the lower Yangtze Platform fold belt between the Dabie Orogenic Belt and the Jiangnan Massif. Analyses of the structural deformation characteristics of both the contact zone and the interior of the pluton are used to explain its emplacement mechanism. The foliation and lineation of the pluton, consisting of the oriented distribution of dark minerals and xenoliths, mainly concentrate along the margin of the pluton. Toward the center of the pluton, the foliation structure becomes weak, showing intense compression formation at the margin, and reflecting the conformable intrusion of the pluton. The relatively gentle lineation is evidence of a rotatory emplacement mechanism. Relatively steep marginal foliation reflects compression expanding. Affected by the thermal power of the pluton, the metamorphism of the contact zone has zonation. Both the strike of the axial plane of fold at the contact zone and that of the flow cleavage of the ductile shear zone are consistent with the boundary of the pluton, which reflects the speciality of conformable intrusion. The hinges of the folds are mostly inclined and erect, reflecting both the rotation of the pluton and its upward spiraling emplacement mechanism. Boudins developed in both the contact zone and the steep strata indicate the emplacement characteristic of the ballon expanding. The surrounding rock of the contact zone shortens horizontally. The average percentage of shortening is 39.7%, which further proves the mechanism of the pluton expanding, and the space occupied by the active expanding intrusion was provided by the shortening of the surrounding rock. The left-lateral shear shown by the ductile shear zone and the rheomorphic fold reveals that the pluton emplacement and the deformation of surrounding rock are controlled by a NNE-striking left-lateral shear stress field. These characteristics of pluton structures provide a mechanism of emplacement. In the deep, the pluton apirally rose left lateral, and in the shallow, the one forcefully emplaced balloningly. 展开更多
关键词 Fenghuangshan Pluton emplacement mechanism Cu-Au mineralization TONGLING anhui
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An investigation of weed seed banks reveals similar potential weed community diversity among three different farmland types in Anhui Province, China 被引量:4
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作者 HE Yun-he GAO Ping-lei QIANG Sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第4期927-937,共11页
Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey ... Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey of weed seed banks was conducted in 2 280 fields at 228 sites of 62 locations representing three different types of farmland(95 paddy, 73 summer-ripe, and 60 autumn-ripe farmlands) along the bank of the Yangtze River in Anhui Province, China. A total of 43 families and 174 species of weeds were found in these weed seed banks. A comparison of the composition of weed groups in the seed banks showed that the species number and density percentage of grass, sedge and broadleaf weed groups were similar among the different types of farmland. The seed banks of all three farmland types shared 71 common weed species, accounting for 40.80% of the total number of species. These common weeds, which were both associated and not associated with crops, accounted for 91.71% of the total dominance degree among all farmland types. The crop-associated weed species were distributed in all soil layers of each farmland type. The Shannon-Wiener index H′(description of species diversity which is more sensitive to dense species) and Pielou's evenness index J(description of species evenness) in summer-ripe farmland were similar to those in autumn-ripe farmland but differed from those in paddy farmland. However, the Simpson's index D(description of species diversity which is more sensitive to sparse species) was similar among all three farmland types. The results of similarity comparison indicated that although the aboveground weed community differed among the different cropping patterns, the weed species composition in the soil seed bank was still similar. Consequently, our results demonstrate that after the implementation of long-term monoculture patterns, weed species compositions in the soil seed bank in different farmlands become homogenized regardless of the crop type. 展开更多
关键词 species compositi on domi nance degree COMM UNITY similarity COMM UNITY variati on anhui Province
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