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Alpine Ecosystems of Northwest Yunnan,China:an Initial Assessment for Conservation 被引量:4
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作者 Ruth Sherman Renee Mullen +2 位作者 LI Haomin FANG Zhendong WANG Yi 《Journal of Mountain Science》 SCIE CSCD 2007年第3期181-192,共12页
Implementing conservation actions on-the-ground is not a straightforward process,especially when faced with high scientific uncertainty due to limited available information. This is especially acute in regions of the ... Implementing conservation actions on-the-ground is not a straightforward process,especially when faced with high scientific uncertainty due to limited available information. This is especially acute in regions of the world that harbor many unique species that have not been well studied,such as the alpine zone of the Hengduan Mountains of Northwest Yunnan (NWY),a global biodiversity hotspot and site of The Nature Conservancy’s Yunnan Great Rivers Project. We conducted a quantitative,but rapid regional-level assessment of the alpine flora across NWY to provide a broad-based understanding of local and regional patterns of the alpine flora,the first large-scale analysis of alpine biodiversity patterns in this region. Multivariate analyses were used to classify the major plant community types and link community patterns to habitat variables. Our analysis indicated that most species had small distributions and/or small population sizes. Strong patterns emerged with higher diversity in the more northern mountains,but beta diversity was high,averaging only 10% among sites. The ordinations indicated that elevation and geographic location were the dominant environ-mental gradients underlying the differences in the species composition among communities. The high beta diversity across the alpine of these mountains implies that conservation strategies ultimately will require the protection of large numbers of species over a large geographical area. However,prioritiza-tion should be given to areas where potential payoffs are greatest. Sites with high species richness also have a greater number of endemic species,and,by focusing efforts on these sites,conservation investments would be maximized by protecting the greatest number of unique species. 展开更多
关键词 Biodiversity hotspot cluster analysis plant community ecology conservation action GRAZING Hengduan Mountains non-metric multidimensional scaling plant species richness World Heritage Site Yunnan Great Rivers Project(YGRP) alpine ecosystems China
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Studies on the Community Structures of Meiofauna and Marine Nematode at Six Stations in the Southern Yellow Sea,China 被引量:10
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作者 HUANGYong ZHANGZhinan LIUXiaoshou 《Journal of Ocean University of China》 SCIE CAS 2005年第1期34-42,共9页
Meiofauna (0.031-0.5 mm) were sampled and studied at a grid of six stationsduring the cruise of investigation for over winter ground of anchovy (Engraulis japonicus) in theSouthern Yellow Sea, China in January 2003. T... Meiofauna (0.031-0.5 mm) were sampled and studied at a grid of six stationsduring the cruise of investigation for over winter ground of anchovy (Engraulis japonicus) in theSouthern Yellow Sea, China in January 2003. Total meiofauna individuals averaged (1.162 ± 0.347) x10^6 ind m^(-2) and the corresponding biomass 1.748 ± 0.72 g dwt m^(-2) with the maximum 2.35 g dwtm^(-2) at Station 9594 and the minimum 0.537 g dwt m^(-2) at Station 11794. A total of fourteentaxa were identified. Free living marine nematodes were the most dominant group with an averageabundance of (1.026 ± 0.206) x 10~6 ind m^(-2), accounting for 88.5% of total numbers, and anaverage of 85.4% lived in the surface layer (0-2cm) of sediments. The individual dry weight wascalculated, which ranges from 0.01 μg to 31.32 μg with an average of 0.261 μg. One hundred andforty two species or taxa of free-living marine nematodes belonging to 89 genera, 24 families and 4orders were identified. Six of them were new species. The common dominant species were Dorylaimopsisrabalaisi, Sphaerolaimus balticus, Sphaerolaimus mini-tus, Metalinhomoeus longicauda,Prochromadorella attenuata., Campylaimus sp. 1, Vasostoma sp. 1, Daptonema nor-mandicum,Paramonohystera riemanni, and Promonhystera sp. 1. According to cluster analysis of Primer 5.0, thesix stations were clustered into 2 groups with similar species composition at 40% similarity. Thespecies diversity index (H′), evenness index (J) and species richness index (d) of nematode werecalculated and analyzed. Correlation analysis with respect to environmental factors showed that theabundance of meiofauna had a significant correlation with the median diameter of sediment (Md_φ).The species richness of nematodes had a highly significant correlation with Chl-a and significantcorrelations with Pha-a and Chl-a + Pha-a. 展开更多
关键词 MEIOFAUNA free-living marine nematodes benthic ecology communitystructure yellow sea of China
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Variation in downwelling diffuse attenuation coefficient in the northern South China Sea 被引量:2
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作者 王桂芬 曹文熙 +1 位作者 杨顶田 许大志 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第3期323-333,共11页
The diffuse attenuation coefficient for downwelling irradiance(Kd(λ)) is an important parameter for ocean studies.Based on the optical profile data measured during three cruises in the northern South China Sea in aut... The diffuse attenuation coefficient for downwelling irradiance(Kd(λ)) is an important parameter for ocean studies.Based on the optical profile data measured during three cruises in the northern South China Sea in autumn from 2003 to 2005,variations in the Kd(λ) spectra were analyzed.The variability of Kd(λ) shows much distinct features in both magnitude and spectra pattern,it is much higher in coastal waters than that of open oceanic waters;and the blue-to-green(443/555) ratio of Kd(λ) tends to increase with chlorophyll a concentration([Chl-a]) from open ocean to coastal waters.These characteristics can be explained most by the increase of aw+p(443)/aw+p(555) with [Chl-a].In short waveband,the relation between Kd(λ)-Kw(λ) and [Chl-a] can be well described by a power law function,indicating the large contribution of phytoplankton to the variations in Kd(λ).As for the spectral model of the diffuse attenuation coefficient,there are good linear relationships between Kd(490) and Kd(λ) in other wavelengths with own slope and intercept of a linear functions in the spectral range 412-555 nm.Kd(490) is well correlated with the spectral ratio of remote sensing reflectance;and should enough measurement data are given,this empirical algorithm would be used in the Kd(λ) retrieval from ocean color satellite data.The variation in Kd(λ) provides much useful information for us to study the bio-optical property in the northern South China Sea. 展开更多
关键词 the downwelling diffuse attenuation coefficient chlorophyll a bio-optical model the northern South China Sea
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A Landscape Pattern Analysis Method Based on Boundaries and Nodes:A Case Study in Upper Minjiang River,China 被引量:3
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作者 WEN Qingchun LI Xiuzhen +5 位作者 HE Hongshi HU Yuanman CHEN Xin CHANG Yu WANG Wei BU Rencang 《Chinese Geographical Science》 SCIE CSCD 2014年第1期50-59,共10页
Traditionally,patch-based analysis at the landscape scale fragmentation has been used in the study of landscape ecology while the study of boundary and node has not been considered as much detail until recently.This s... Traditionally,patch-based analysis at the landscape scale fragmentation has been used in the study of landscape ecology while the study of boundary and node has not been considered as much detail until recently.This study investigated the possibility of applying boundary-and node-based methods in landscape pattern analysis to the upper reaches of the Minjiang River in the southwestern China.Boundary-based and node-based landscape indices were selected to be used in analyzing changes in landscape patterns,and the results were compared with analysis using traditional pattern indices.We compared the responses of patch-area-based,boundary-length-based and node-number-based indices,and concluded that boundary-based and node-based indices are more sensitive to disturbance than patch-based indices with various patterns,and node-based indices are even more sensitive than boundary-based ones.Thus,the results suggest that boundary-based and node-based pattern analysis methods provide helpful supplementary information to traditional patch-based pattern analysis methods.The results about pattern dynamics of landscapes in the upper reaches of the Minjiang River based on boundaries and nodes showed that with human disturbance,the dominance of forest landscape was weakened by other landscape types;thus the landscape pattern of the study area became more homogeneous and the boundary network became more complex.These changes further augmented disturbance interfaces in the landscape and increased the possibilities of further landscape fragmentation. 展开更多
关键词 LANDSCAPE pattern index PATCH BOUNDARY NODE Minjiang River
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Bioinformatic Analysis of BBTV Satellite DNA in Hainan 被引量:1
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作者 Nai-tong Yu Tuan-cheng Feng Yu-liang Zhang Jian-hua Wang Zhi-xin Liu 《Virologica Sinica》 SCIE CAS CSCD 2011年第4期279-284,共6页
Banana bunchy top virus (BBTV),family Nanaviridae,genus Babuvirus,is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants.It is the most common and most destructive of all ... Banana bunchy top virus (BBTV),family Nanaviridae,genus Babuvirus,is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants.It is the most common and most destructive of all viruses in these plants and is widespread throughout the Asia-Pacific region.In this study we isolated,cloned and sequenced a BBTV sample from Hainan Island,China.The results from sequencing and bioinformatics analysis indicate this isolate represents a satellite DNA component with 12 DNA sequences motifs.We also predicted the physical and chemical properties,structure,signal peptide,phosphorylation,secondary structure,tertiary structure and functional domains of its encoding protein,and compare them with the corresponding quantities in the replication initiation protein of BBTV DNA1. 展开更多
关键词 Banana bunchy top virus SATELLITE PREDICTION
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Report of Pontoniinae Shrimps (Crustacea: Decapoda) Collected by Joint Chinese-German Marine Biology Expeditions to Hainan Island, South China Sea. Ⅲ. Periclimenes
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作者 李新正 刘瑞玉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第1期89-100,共12页
The present paper reports 12 species of genus Periclimenes, subfamily Pontoniinae, collected from Hainan Island, South China Sea, by the Joint Chinese-German Marine Biology Expeditions, in which, Periclimenes consobri... The present paper reports 12 species of genus Periclimenes, subfamily Pontoniinae, collected from Hainan Island, South China Sea, by the Joint Chinese-German Marine Biology Expeditions, in which, Periclimenes consobrinus and P. tenuipes are new records from Chinese waters, and Periclimenes amymone, P. holthuisi, P. soror, and P. toloensis are recorded for the first time from Hainan Island. 展开更多
关键词 Pontoniinae Periclimenes Hainan Island
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Physical Changes Trends and Urban-Rural Comparative Research of Han Children Aged 7 in Hunan
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作者 Yufeng Guo Hongyan Zhou Mingdong Xiao 《International English Education Research》 2015年第2期26-29,共4页
The physical health has become a hot topic in today's society, in order to understand the physical health status quo of Hunan Han schoolchildren to collect 1985 -2010 six national student physical research data, sele... The physical health has become a hot topic in today's society, in order to understand the physical health status quo of Hunan Han schoolchildren to collect 1985 -2010 six national student physical research data, select Hunan Province Han schoolchildren in seven years (school age) and rural men and women a total of four set of data (1985 to 1995 due to the minimum age of 7 years old monitor, so the index is also unified in 2000 after seven years of age selected set of data), performed with SPSSI8.0 Comparative Analysis of physique changing trends and urban and rural areas. The results show that: the physical development of children reach school age Hunan Province Han good, but the boys of height, weight and chest are still differences between urban and rural areas; respiratory function developmental level decreased to varying degrees, both urban and rural areas need strengthening exercise to improve respiratory function. Speed, endurance, power and strength endurance, strength, quality has a different rate of increase quality trends, and most has no specific differences between urban and rural areas; Felicity decline, but rural girls group performance has increased, shortening the urban and rural areas gap. Due to substantial improvements in the living conditions of rural, urban and rural differences have been gradually reduced, but from learning, family, social pressure, and the lack of good exercise habits, sports teachers and other reasons that students can not ensure adequate exercise time, which affects the Han physical level students in Hunan province, hoping to enter primary school-age children start, the implementation of the "National Student Physical Health Standard" and strive to ensure that physical education and physical exercise, strengthening and improving school sports to promote quality education, comprehensively enhance physical fitness of students in Hunan province. 展开更多
关键词 Hunan Province HAN 7-Year-Olds PHYSIQUE Urban-Rural Comparison
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巴南,我心中的天堂
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作者 张珏函 《作文世界(初中版)》 2004年第5期54-54,共1页
巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。... 巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。请大家看看,他们是怎样描绘他们的家乡巴南的;在他们的心目中,巴南是怎样一个可爱而快速发展的地方。让我们和他们一起去领略巴南的美丽与多姿多彩吧。 展开更多
关键词 南中学生 大家看 温泉度假村 跳石镇 圣灯 舍身崖 桥口 铁钩
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朋友,请到我家乡来
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作者 潘灿 《作文世界(初中版)》 2004年第5期49-50,共2页
巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。... 巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。请大家看看,他们是怎样描绘他们的家乡巴南的;在他们的心目中,巴南是怎样一个可爱而快速发展的地方。让我们和他们一起去领略巴南的美丽与多姿多彩吧。 展开更多
关键词 南中学生 大家看 悬崖边 圣灯 植物基因 孙悟空大闹天宫 森林茂密 旅游资源 建文帝
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豆花香自木洞来
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作者 宋孝敏 《作文世界(初中版)》 2004年第5期52-53,共2页
巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。... 巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。请大家看看,他们是怎样描绘他们的家乡巴南的;在他们的心目中,巴南是怎样一个可爱而快速发展的地方。让我们和他们一起去领略巴南的美丽与多姿多彩吧。 展开更多
关键词 南中学生 自木 大家看 一元钱 黄埔军校遗址 蔡珍 木洞镇 棒棒鸡 轻松自在
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李家沱,我为你自豪
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作者 孙英垅 《作文世界(初中版)》 2004年第5期51-51,共1页
巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。... 巴南是我国第四个直辖市重庆市的一个区。改革开放以来,尤其是党中央发出开发西部的号召以来,作为我国最年轻的直辖市重庆,不仅自身得到了很大发展,而且在开发西部中也发挥着越来越重要的作用。这里,我们编发了一组巴南中学生的习作。请大家看看,他们是怎样描绘他们的家乡巴南的;在他们的心目中,巴南是怎样一个可爱而快速发展的地方。让我们和他们一起去领略巴南的美丽与多姿多彩吧。 展开更多
关键词 南中学生 大家看 遇水架桥 国家法令 经济发展 长途汽车站 长江二桥 批发市场 五脏俱全
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Diversity of Mesozoic tin-bearing granites in the Nanling and adjacent regions,South China:Distinctive mineralogical patterns 被引量:15
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作者 WANG RuCheng XIE Lei +2 位作者 LU JianJun ZHU JinChu CHEN Jun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第11期1909-1919,共11页
The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or (topaz-) alb... The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or (topaz-) albite-lepidolite (zinnwaldite) granites, and geochemically correspond to mealuminous and peraluminous types, respectively. Mineralogical studies demonstrate highly distinctive and critical patterns for each type of granites. In mealuminous tin granites amphibole, biotite and perthite are the typical rock-forming mineral association; titanite and magnetite are typical accessory minerals, indicating highjO2 magmatic conditions; cassiterite, biotite and titanite are the principal Sn-bearing minerals; and pure cassiterite has low trace-element contents. However, in peraluminous tin granites zirmwaldite-lepidolite, K-feldspar and albite are typical rock-forming minerals; topaz is a common accessory phase, indicative of high peraluminity of this type of granites; cassiterite is present as a uniquely important tin mineral, typically rich in Nb and Ta. Mineralogical distinction between the two types of tin granites is largely controlled by redox state, volatile content and differentiation of magmatic melts. In oxidized metaluminous granitic melts, Sn4+ is readily concentrated in Ti-bearing rock-forming and accessory minerals. Such Sn-bearing minerals are typical of oxidized tin granites, and are enriched in granites at the late fractionation stage. In relatively reduced peraluminous granitic melts, Sn2+ is not readily incorporated into rock-forming and accessory minerals, except for cassiterite at fractionation stage of granite magma, which serves as an indicator of tin mineralization associated with this type of granites. The nature of magma and the geochemical behavior of tin in the two types of granites thus result in the formation of different types of tin deposits. Metaluminous granites host disseminated tin mineralization, and are locally related to deposits of the chlorite quartz-vein, greisen, and skarn types. Greisen, skarn, and quartz-vein tin deposits can occur related to peraluminous granites, but disseminated mineralization of cassiterite is more typical. 展开更多
关键词 Metaluminous tin granites Peraluminous granites Mineral assemblages Mineralogical indication of mineralization Nanling and adjacent regions
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Growth of a polymetallic nodule from northwestern continental margin of the South China Sea and its response to changes in paleoceanographical environment of the late Cenozoic 被引量:6
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作者 ZHANG ZhenGuo DU YuanSheng +4 位作者 WU ChangHang FANG NianQiao YANG ShengXiong LIU Jian SONG ChengBing 《Science China Earth Sciences》 SCIE EI CAS 2013年第3期453-463,共11页
In the northern South China Sea, the accumulation of enormous quantities of terrigenous sediment during Cenozoic rendered well-developed polymetallic nodules very rare. In this study, we analyzed a polymetallic nodule... In the northern South China Sea, the accumulation of enormous quantities of terrigenous sediment during Cenozoic rendered well-developed polymetallic nodules very rare. In this study, we analyzed a polymetallic nodule from the northwestern conti- nental margin of the South China Sea using microscopic mineralogical observation, electron probes, X-ray diffraction (XRD), ICP-MS, and Be isotope dating. We found the nodule's shell layers rich in different types of microstructures, including co- lumnar, laminar, stack-like, petal-like, and porphyritic structures. The major mineral components of the nodule are MnO2. Unlike nodules from the eastern Pacific basin, this nodule has high contents in Fe, Si, A1, and REEs but low contents in Mn, Cu, Co, and Ni. The Mn/Fe ratio is also low and the average REEs content is 1370.4 ppm. There is a strong positive anomaly of Ce; and the Be (beryllium) isotope dating shows the initial time of growth of the nodule to be about 3.29 Ma. The inner compact layer formed from 3.29 Ma to about 1.83 Ma. The laminar and stack-like structures and the low contents of the terri- genous elements such as Fe, Si, REE, and A1 indicate the paleoceanographical environment with weak undersea currents and favorable oxidizing conditions. From 1.83 Ma to 0.73 Ma, the growth rate of the nodule increased by about 3%; the micro- structures formed during this period are stack-like and columnar. The contents of Si and A1 are increased by nearly 10%, indi- cating an increase of terrigenous sediment input in the northern South China Sea. The content of Ce is decreased by about 16% indicating a significant weakening of the oxidizing conditions at the seabed. From 0.73 Ma to 0.69 Ma, the growth rate of the nodule rapidly rose up to 8.27 times that of the nodule's average growth rate, and the contents of Fe, A1, and REEs in the layer also increased, forming a loose layer characterized by oolitic, granular, porphyritic, and petal-like structures, indicating the paleoceanographical environment with a high sedimemtation rate and abundant supply of terrigenous sediment in the northern South China Sea. From 0.69 Ma to 0.22 Ma, the growth rate of the nodule suddenly slowed and the outer compact layer formed. Contents of Fe, Si, REE, A1, Mn, Cu, Co, and Ni in this layer were significantly lower than in other layers. The main structures of the layer are laminar and fissure filling structures. These reflect the paleoceanographical environment with stable undersea currents, poor oxidizing conditions, and other conditions not conducive to nodule growth. The growth process of nodule S04-1DG-1 was found to respond sensitively to the changes of the paleoceanographical environment of the northern South China Sea during the late Cenozoic. 展开更多
关键词 polymetallic nodules growth process late Cenozoic paleoceanographical environment RESPONSE northwestern conti-nental margin of South China Sea
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Phosphatic microspherules and their geobiological implications from the Frasnian-Famennian transition at the Yangdi section, Guilin, South China 被引量:2
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作者 HUANG Cheng GONG YiMing 《Science China Earth Sciences》 SCIE EI CAS 2014年第5期943-956,共14页
Abundant perfectly-preserved phosphatic microspherules have been discovered across the Frasnian-Famennian (F-F) transition from the Yangdi section in Guilin, Guangxi, South China. They are mostly spherical or ellipt... Abundant perfectly-preserved phosphatic microspherules have been discovered across the Frasnian-Famennian (F-F) transition from the Yangdi section in Guilin, Guangxi, South China. They are mostly spherical or elliptical in shape and about 150 gin in diameter with smooth exterior surfaces. Each microspherule consistently possesses a small dimple on the surface. The internal texture of microspherules consists of concentric light-colored apatite and dark-colored organic matter bands alternating around a central core. Conodonts have also been found preserved together with phosphatic microspherules in the same horizon, and the abundance of the former is obviously higher than that of the latter. Laser Raman spectral studies show close similarities in spectral patterns between the outer shells of phosphatic microspherules and the blade of the conodont genus Palmatolepis sp., as well as between the microspherule nucleus and the platform of the same conodont genus. Furthermore, the statistical results and geochemical data demonstrate that the elevated abundance of phosphatic microspherules roughly coincides with the blooms of bacteria and algae, but is later than the sharp increase of oceanic nutrients. The phosphatic microspherules are inter- preted here to be the 'otoliths' secreted by conodont animals based on the compositional similarities between phosphatic mi- crospherules and conodonts and their interrelated abundances. In addition, an analogous study reveals morphological and tex- tural similarities between fish otoliths and phosphatic microspherules. The formation of phosphatic microspherules is probably related to seawater eutrophication. We speculate that the explosive growth of bacteria and algae is probably caused by the en- richment of nutrients that is most likely associated with the increase of terrestrial inputs, submarine hydrothermal activities or the upwelling anoxic bottom waters in the late Devonian, which would stimulate the conodont animals to secrete phosphatic microspherules--the 'otoliths' of conodont animals. This study reveals the coupling relationship between organisms and envi- ronments from the perspective of phosphatic microspherules and provides new evidence for the cause of faunal crisis during the Late Devonian F-F transition. 展开更多
关键词 microspherules conodont animal otoliths EUTROPHICATION DEVONIAN F-F South China
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