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New data regarding acritarch biostratigraphy from the Early-Middle Cambrian Kaili Formation in Chuandong,Guizhou Province,China

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Progress in Natural Science:Materials International 2009年第1期19卷 107-114页

作者： Leiming Yin a,Ruidong Yang b,Jin Peng c,Fanfan Kong a a nanjing institute of Geology and Palaeontology,chinese academy of {4.,nanjing 2.0008,China b College of Resource and Environment of Guizhou University,Guiyang 550003,China c Department of {4. of nanjing University,nanjing 2.0093,China [a]nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China [b]College of Resource and Environment of Guizhou University Guiyang 550003 China [c]Department of Sciences of Nanjing University Nanjing 210093 China

Previous studies had evaluated acritarchs from the Balang and Pingzhai sections of the Early-Middle Cambrian Kaili Formation in east Guizhou,*** results of these studies suggest that the acritarchs in these sections have potential biostratigraphic *** recently,34.samples collected from 83 m lower part of the Lower-Middle Cambrian Kaili Formation in the Jianshan section of Chuandong,Guizhou Province were prepared for palynological *** of these samples revealed a distinct change in the acritarch assemblages at the bed,which was approximately 4. m above the bottom of the Kaili *** findings suggest a boundary represented by an important alteration of the ecological *** addition,the position of the acritarch biostratigraphic change is somewhat higher than the boundary between Cambrian Series 2 and Series 3 based on trilobites found in the same *** indicates that the distinct change in acritarch assemblages is similar to the change in trilobite assemblages that occurs around the boundary between Cambrian Series 2 and Series ***,acritarch biostratigraphy can provide data that can be used to define the base of Cambrian Series 3 in this region,and possibly worldwide.

关键词： Acritarchs Lower-Middle Cambrian Kaili Formation Jianshan section Chuandong

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The Age and Character of the Yu'erhong Flora from Yumen, Gansu

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 329-338,342-343页

作者： Shen Guanglong, Wu Xiuyuan, Wang Jun and Liu Huaqin Department of Geology, Northwest U niversity, Xi’an, Shaanxi nanjing institute of Geology and Palaeontology,chinese academy of {4., nanjing, jiangsu 1 Department of Geology Northwest University Xi' an Shaanxi2Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing Jiangsu

From a fresh field investigation, it has been ascertained that the Late Palaeozoic Yu'erhong (Yuernhung) flora from Yu'erhong, Yumen, Gansu, northwestern China, studied by Bohlin in 1971 includes plants from the Westphalian Yangfukou Formation and the Stephanian to Sakmarian Taiyuan Formation. The Yu'erhong flora from the Yanghukou Formation is dominated by Euramerican elements with a few elements of the Cathaysian flora. No Angarian elements have be found in this section for lack of Late Permian strata. The specimens studied by Bohlin might possibly come from the upper part of the Upper Permian at tne southeastern corner . of the Yu'erhong basin. Those fossils from different horizons and localities might be mixed with each other during collection ;so they fail to reflect the exact horizon of certain plant fossils.

关键词： Yu'erhong flora Yanghukou Formation Taiyuan Formation Yumen Gansu

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Accumulation and Fractionation of Rare Earth Elements in a Soil-Wheat System

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Pedosphere 2006年第1期16卷 82-90页

作者： DING Shi-Ming LIANG Tao ZHANG Chao-Sheng WANG Li-Jun SUN Qin nanjing institute of geography ＆ limnology Chinese Academy of Sciences Nanjing 210008 （China） institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （ China） Department of geography and Environmental Change institute National University of Ireland Galway （Ireland） State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 （China）

Time series bioaccumulation of rare earth elements （REEs） in field-grown wheat with and without a dressing of extraneous REE fertilizer at different growth stages and fractionation of REEs during their transport in a soil-wheat system were determined. Time-dependent accumulation of extraneous REEs was found in different parts of wheat. An upward transport of extraneous REEs from roots to shoots under a soil dressing and a downward transport from leaves to roots with a foliar dressing were also observed. Moreover, fractionation of REEs occurred in the soil-wheat system. Compared to the host soil a positive Eu anomaly in the stems and grains as well as heavy REE enrichment in the grains were found. The ability of the different wheat organs to fractionate Eu from the REE series was ranked in the order of sterns 〉 grains 〉 leaves 〉 roots.

关键词： accumulation fractionation rare earth elements wheat

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Nitrogen Mineralization of Prunings of Six N_2-Fixing Hedgerow Species in a Dry Valley of the Jinsha River

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Pedosphere 2002年第1期12卷 25-31页

作者： SUN HUI, TANG YA and ZHAO QIGUO institute of Soil Science, the chinese academy of sciences, nanjing, 2.0008 (China) Chengdu institute of Biology, the chinese academy of sciences, Chengdu 61004. (China) institute of Soil Science the Chinese Academy of Sciences Chengdu 610041 Ghengdu institute of Biology the Chinese Academy of Sciences Chengdu 610041 institute of Soil Science the Chinese Academy of Sciences Nanjing 210008

A litterbag experiment of 12 weeks was conducted to study nitrogenmineralization process of prunings of six nitrogen-fixing hedgerowspecies in a dry valley of the Jinsha River. Prunigns wereincorporated into soil or used as mulch. The results indicated thatpruning N of the six hedgerow species was mineralized fast in thefirst week and then decreased slowly in the rest of the study *** prunings were incorporated into soil, the amount of nitrogenmineralized by the end of the first week accounted for 69.9/100,58.2/100, 54.5/100, 4..0/100, 29.6/100 and 20.6/100 of the total N inprungins of Desmodium rensonii, Tephrosia candida, Leucaenaleucoephala, Albizia yunnanensis, Acacia dealbata, and Acaciamearnsii, respectively.

关键词： contour hedgerow system mineralization N, prunings

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Focal plane wave-front sensing algorithm for high-contrast imaging

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Science China(Physics,Mechanics & Astronomy) 2009年第8期52卷 1284-1288页

作者： DOU JiangPei1,2,3,REN DeQing1,2,4.ZHU YongTian1,2 & ZHANG Xi1,2,3 1 National Astronomical Observatories/nanjing institute of Astronomical Optics & Technology,chinese academy of {4.,nanjing 2.004.,China 2 Key Laboratory of Astronomical Optics & Technology,nanjing institute of Astronomical Optics & Technology,chinese academy of {4.,nanjing 2.004.,China 3 Graduate University of{14.,Beijing 10004.,China 4.Physics & Astronomy Department,California State University Northridge,18111 Nordhoff Street,Northridge,California 91330-8268,USA National Astronomical Observatories/nanjing institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042 China Key Laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042 China Graduate University of chinese academy of sciences Beijing 100049 China Physics & Astronomy Department California State University Northridge 18111 Nordhoff Street Northridge California 91330-8268 USA

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star.A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error of an optical *** derive an algorithm for the wave-front measurement directly from 3 focal plane *** 3 images are achieved through a deformable mirror to provide specific phases for the optics *** introduce an extra amplitude modulation on one deformable mirror configuration to create an uncorrelated wave-front,which is a critical procedure for wave-front *** simulation shows that the reconstructed wave-front is consistent with the original wave-front theoretically,which indicates that such an algorithm is a promising technique for the wave-front measurement for the high-contrast imaging.

关键词： high-contrast imaging multi-image algorithm speckle nulling technique wave-front sensing

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Pollen records of Holocene vegetation and climate changes in the Longzhong Basin of the chinese Loess Plateau

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Progress in Natural Science:Materials International 2007年第12期17卷 1445-1456页

作者： Tang Lingyu1 and An Chengbang2(1. nanjing institute of Geology and Paleontology, chinese academy of sciences, nanjing {4.008, China 2. Key Laboratory of Western China’s Environment Systems, MOE, Lanzhou University, Lanzhou 730000, China) nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Key Laboratory of Western China’s Environment Systems MOE Lanzhou University Lanzhou 730000 China

Pollen records with an average time resolution of 20-2.0 years from Holocene loess sections at Dingxi, Qin'an, and other localities of Gansu Province reveal a detailed history of vegetation and climate changes in the western Loess Plateau. For most time of the Holocene, the landscape was dominated by grasslands or forest steppes. However, during the middle Holocene (7.5-5.8 ka BP), relatively dense forests developed, and the endemic vegetation flourished, suggesting a much warmer and more humid climate condition than the present. Superimposed upon this general pattern are several dry intervals marked by the episodic expansion of grasslands or forest steppe. Xeric vegetation expanded after 3.8 ka BP, indicating a trend towards dry conditions.

关键词： pollen records glasslands coniferous forests Holocene Loess Plateau.

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New species and new records of diatoms from Lake Fuxian,China

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Journal of Systematics and Evolution 2010年第1期48卷 65-72页

作者： 1 Yan-Ling LI 1 Zhi-Jun GONG 2 Chun-Chao WANG 1 Ji SHEN 1(State Key Laboratory of Lake Science and Environment,nanjing institute of geography and limnology,{4. academy of sciences,nanjing 2.0008,China) 2(nanjing institute of Geology and Palaeontology,{4. academy of sciences,nanjing 2.0008,China) (State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China) (nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China) *Correspondence: Yan-Ling LI *Correspondence: *?Author for correspondence. E-mail: ylli@*** Tel.: 86-25-8688214. Fax: 86-25-57713063.

One new species,four newly recorded genera,and two newly recorded species of diatoms are described from *** are Sellaphora fuxianensis ***,Sellaphora Mereschkowsky,Karayevia Round & Bukhtiyarova,Placoneis Mereschkowsky,Fallacia Stickle & Mann,Placoneis prespanensis Levkov,Krstic & Nakov,and Fallacia lucinensis(Hustedt) *** taxa were collected from Lake Fuxian in Yunnan Province,*** species were observed with light and scanning electron microscopes,and their taxonomic characters are discussed.

关键词： China diatom new records new species.

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Soil Organic Carbon Storage in China

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Pedosphere 2004年第4期14卷 491-500页

作者： XIEXian-Li SUNBo ZHOUHui-Zhen LIAn-Bo instituteofSoilScience ChineseAcademyofSciencesNanjing210008（China）. geographyCollege NanjingNormalUniversityNanjing210097（China）

Soil organic carbon (SOC) storage under different types of vegetations in China were estimated using measured data of 2 4.0 soil profiles to compare SOC density distribution between different estimates, to map the soil organic carbon stocks under different types of vegetation in China, and to analyze the relationships between soil organic carbon stocks and environmental variables using stepwise regression analyses. Soil organic carbon storage in China was estimated at 69.38 Gt (10 15 g). There was a big difference in SOC densities for various vegetation types, with SOC distribution closely related to climatic patterns in general. Stepwise regression analyses of SOC against environmental variables showed that SOC generally increased with increasing precipitation and elevation, while it decreased with increasing ***, the important factor controlling SOC accumulation for forests was elevation, while for temperate steppes mean annual temperature dominated. The more specific the vegetation type used in the regression analysis, the greater was the effect of environmental variables on SOC. However, compared to native vegetation, cultivation activities in the croplands reduced the influence of environmental variables on SOC.

关键词： China environmental factors soil organic carbon storage vegetation

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The changes of Lop Nur Lake and the disappearance of Loulan

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Journal of Arid Land 2010年第4期2卷 295-303页

作者： ZhiChao WANG Xinjiang institute of Ecology and geography, chinese academy of sciences, Urumqi 830011, China chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China

The causes of the disappearance of the ancient town of Loulan in Xinjiang, China have been generally agreed to derive from two factors: human activities and natural factors (environmental variations). In this paper, the Muzart Glacier was selected as an example, and found that the length of the glacier has been gradually decreasing and the snow line has been retreating to a higher altitude, both results contributing to a decrease in river flow below the Muzart Glacier. From the distribution of moraines in the Tianshan Mountains and adjacent areas in different periods, the paper speculates that there have been four minor glacial periods since the Quaternary. Although the durations and scales of the four minor glacial periods were different, they all indirectly influenced the formation and disappearance of the Lop Nur Lake. The events of the fourth minor glacial period are the important impact factors in the existence and disappearance of Loulan. Whether the disappearance of Loulan can be related to the events of the three previous minor glacial periods needs further investigation.

关键词： glacier moraine Loulan Lop Nur

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Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2 and Luo Zhexian2(1. institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029, China 2. nanjing University of Information sciences & Technology, nanjing 2.004., China) institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China nanjing University of Information sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 12.0 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

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