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Confirmation of a natural hybrid species in Petrocosmea(Gesneriaceae) based on molecular and morphological evidence

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Journal of Systematics and Evolution 2011年第5期49卷 449-463页

作者： 1,3.Zhi-Jing QIU 2~Zu-Li YUAN 1~Zhen-Yu LI 1~Yin-Zheng WANG 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,{3. 100093.China) 2(Henan Agricultural university,Zhengzhou 45002,China) 3.graduate School of the chinese academy of sciences,beijing 100049,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate School of the chinese academy of {3. Beijing 100049 China) (Henan Agricultural university Zhengzhou 45002 China)

A natural hybrid species in Petrocosmea named Longianthera in Yanshan County,Yunnan Province is confirmed for the first time based on molecular and morphological *** character count procedure of the variable characters show that Longianthera populations are characteristic of the intermediate morphological traits between its putative parents Yanshan and Petrocosmea *** nuclear ribosomal internal transcribed spacer region and three chloroplast regions of matK,trnL-F,and trnT-L are sequenced in the putative hybrid and the related *** alignment of DNA sequences and the phylogenetic trees could exclude all the other species in Petrocosmea as the parental species except for Yanshan and *** haplotypes in the 3. internal transcribed spacer sequences and six haplotypes in 42 cpDNA sequences were found from 14 individuals of Longianthera *** analyses of DNA sequences,haplotypes,and phylogenetic trees indicate that Longianthera is likely a hybrid species between its putative parents Yanshan and ***,in which Yanshan might be the most possible maternal *** factors may contribute to the natural hybridization between these two parental species in Petrocosmea,such as the overlapped geographic distribution,habitats,flowering periods,and shared ***,the new species of Yanshan and the natural hybrid species of Longianthera are described.

关键词： chloroplast DNA Gesneriaceae ITS morphology natural hybridization Petrocosmea.

Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

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Science China Earth sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3.1. Key Laboratory of Lake Sedimentation and Environment, Nanjing Institute of Geography and Limnology, chinese academy of sciences, Nanjing 210008, China 2. Institute of Tibetan Plateau Research, chinese academy of sciences, beijing 10085, China 3. graduate university of chinese academy of sciences, beijing 10003., China Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 210Pb and 13.Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14C age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 210Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14C dating is stronger. Based on the analysis on results of 14C, 210Pb and 13.Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C calendar ages, and establish the time sequence for cores CE-1 and CE-2 with result of 210Pb CRS model for the upper 3. cm and re-calculated 14C calendar age for sediments bellow 3. cm. Since 1400 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14C, 210Pb and 13.Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

Compositions of heavy minerals in Northeastern China sandlands and provenance analysis

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Science China Earth sciences 2007年第11期50卷 1715-1723页

作者： XIE Jing1,2 & DING ZhongLi1 1 Institute of Geology and Geophysics, chinese academy of sciences, {3. 100029, China 2 graduate university of chinese academy of sciences, beijing 100049, China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun Buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and tourmalines. Heavy mineral assemblages of these three sandlands consist mainly of garnet, ilmenite, epidote and minor amphibole and magnetite. Garnets consist mainly of high Mg type-A ones (58% on average), and minor type-B ones. Toumalines are mainly composed of Mg-rich and minor Fe-rich ones. Compared with those of central-southern Mongolia and central Tarim, these three sandlands are derived from the Phanerozoic rocks of the Central Asian Orogenic Belt and the Archean and Paleoprotorozoic basement rocks of the North China Craton. Our results provide direct evidence that the present-day sands may be reworked from LGM ones. Differences of heavy mineral composi-tions occur between the samples of the three sandlands and Taklimakan Desert, indicating that the material of the western arid regions contributes little to the eastern sandlands.

关键词： heavy minerals,provenance,Northeastern China,garnet,tourmaline

Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan university Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2, LIU Chuang1, 3.1. Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, China 2. graduate university of chinese academy of sciences, beijing 100049, China 3. College of Resources Science and Technology, beijing Normal university, beijing 100875, China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China College of Resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2000,and the image with the charge-coupled device camera (CCD) on the China-Brazil earth resources satellite (CBERS) in 2008 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2008. There were 12 63..54 hm2 cropland de-creased between 1993.and 2000,and 8 227.6 hm2 cropland de-creased between 2000 and 2008. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the China-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

Evaluation of 10 plant barcodes in Bryophyta (Mosses)

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

作者： 1,2 Yan LIU 3.Hai-Fei YAN 4 Tong CAO 3.Xue-Jun GE 1(Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, China) 2({3. university of the chinese academy of sciences, beijing 100049, China) 3.Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, chinese academy of sciences, Guangzhou 510650, China) 4(College of Life & Environment sciences, Shanghai Normal university, Shanghai 20023., China) (Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China) (graduate university of the chinese {3. of sciences Beijing 100049 China) (Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (College of Life & Environment sciences Shanghai Normal University Shanghai 200234 China)

DNA barcoding is a molecular tool that uses a standardized DNA region to identify *** preliminary study reported here is the first attempt to specifically focus on universality and attributes of candidate barcodes across a wide systematic range of *** tested eight previously proposed plant barcoding regions(atpF-atpH, ITS2, matK, psbK-psbI, rbcL, rpoB, rpoC1, and trnH-psbA) and two popular phylogenetic markers(rps4 and trnL-trnF of cpDNA) in 49 moss species and 9 liverwort species, representing half of the orders in moss *** ITS2, rbcL, rpoC1, rps4, trnH-psbA and trnL-trnF regions showed good universality, and therefore the efficacy of these loci as DNA barcodes was further evaluated in 3. mosses and 2 liverworts, each of which included two to three individuals per *** five loci, ***, rpoC1, rps4, trnH-psbA and trnL-trnF, were easy to amplify and sequence and showed significant inter-specific genetic variability, making them potentially useful DNA barcodes for *** best performing single loci were the rbcL and rpoC1 coding *** loci showed equivalent performance and combinations of them did not greatly increase their discrimination *** addition, phylogenies generated from each of the separate regions and multi-locus combinations by using best-fit and Kimura 2-parameter models were compared, but no significant difference was found.

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

A Test on Different Types of the Time Curve of Hardness Ratio of Gamma-Ray Bursts based on the Curvature Effect

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chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 451-464页

作者： Lan-Wei Jia National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,China {3. School of chinese academy of sciences,beijing 100049,China National Astronomical Observatories/ Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China graduate School of chinese academy of {3. Beijing 100049 China

We analyzed a sample of 66 gamma-ray bursts （GRBs） and statistically confirmed the prediction on the time curve of the hardness ratio of GRBs made by Qin et al. based on the curvature effect. In their analysis, GRB pulses are divided into three types according to the shape of their raw hardness ratio （RHR） time curves, defined as to include the background counts to the signal counts, so as to make use of counts within small time intervals. Of the three types, very hard sources exhibit a perfect pulse-like profile （type 1）, hard bursts possess a pulse-like profile with a dip in the decay phase （type 2）, and soft bursts show no pulse-like profile but have only a dipped profile （type 3.. In terms of the conventional hardness ratio, type 3.sources are indeed generally softer than those of type 1 and type 2, in agreement with the prediction. We found that the minimum value of RHR is sensitive in distinguishing the different types. We propose that GRB pulses can be classified according to the minimum value of RHR and that the different type sources may be connected with different strengths of the shock or/and the magnetic field.

关键词： gamma-rays burst -- gamma-rays observations - methods statistical

Scale effects of leaf area index inversion based on environmental and disaster monitoring satellite data

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Science China Earth sciences 2010年第S1期53卷 92-98页

作者： ZHANG Hao1,LI XiaoWen1,2,CAO ChunXiang1,YANG Hua2,GAO MengXu1,3.ZHENG Sheng1,3.XU Min1,3.XIE DongHui2,JIA HuiCong1,JI Wei1,ZHAO Jian1,3.CHEN Wei1,3.& NI XiLiang1,3.1 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by Institute of Remote Sensing Applications,chinese academy of sciences and {3. Normal university,{3. 100101,China 2 State Key Laboratory of Remote Sensing Science,Jointly Sponsored by {3. Normal university and Institute of Remote Sensing Applications of chinese academy of sciences,{3. 100875,China 3.graduate university of chinese academy of sciences,{13.,China State Key Laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

The spatial distribution of sub-pixel components has an impact on retrieval accuracy,and should be accounted for when inverting a three-dimensional adiative transfer model to retrieve leaf area index(LAI).To investigate this effect,we constructed three realistic scenarios with the same LAI values and other properties,except that the simulated plants had different *** implemented the radiosity method to subsequently produce synthetic bidirectional reflectance factor(BRF) datasets based upon these simulated *** inversion was conducted using these data,which showed that spatial distribution affects retrieval *** inversion was also conducted for LAI based on charge-coupled device(CCD) data from the Environment and Disaster Monitor Satellite(HJ-1),which depicted both forest and drought-resistant crop land *** showed that heterogeneity in coarse-resolution remote sensing data is the main error source in LAI *** spatial distribution of global fractal dimension index,which can be used to describe the area of sub-pixel components and their spatial distribution modes,shows good consistency with the coarse resolution LAI inversion error.

关键词： HJ-1 leaf area index scale effect spatial distribution

Testing local realism in P → VV decays

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Science China(Physics,Mechanics & Astronomy) 2010年第5期53卷 870-875页

作者： LI JunLi1 & QIAO CongFeng1,2 1Department of Physics,graduate university of chinese {3. of sciences,beijing 100049,China 2Theoretical Physics Center for Science Facilities(TPCSF),chinese {3. of sciences,beijing 100049,China Department of Physics Graduate University of Chinese Academy of Sciences Beijing China Theoretical Physics Center for Science Facilities (TPCSF) Chinese Academy of Sciences Beijing China

It was found that the vector meson pair from the pseudoscalar decays can form an entangled *** this work we give out detailed explanations on the polarization correlation of the two entangled vector *** is demonstrated that an experimental test of the Clauser-Horne inequality can be carried out through measuring the azimuthal distribution of four pseudoscalars in the cascade decay ηc→ VV →(PP)(PP),and the measurement of this process is feasible with the current running experiments in tau-charm ***,a brief discussion on the polarization correlation of the two vector mesons from B → VV decays is also presented.

关键词： nonlocality test high energy experiment meson decays

Nitrogen isotopic composition of plant-soil in the Loess Plateau and its responding to environmental change

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chinese Science Bulletin 2009年第2期54卷 272-279页

作者： LIU WeiGuo1,2 & WANG Zheng1,3.1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075, China 2 Xi’an Jiaotong {3., School of Human Settlement and Civil Engineering, Xi’an 710049, China 3.graduate university of chinese academy of sciences, beijing 100049, China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China School of Human Settlement and Civil Engineering Xi’an Jiaotong University Xi’an China graduate university of chinese {3. of sciences Beijing China

The nitrogen isotope of soil is of emerging significance as an indicator of climatic change and biogeochemical cycle of nitrogen in nature systems. In this paper, the nitrogen content and isotopic composition of modern ecosystems from arid and semiarid Loess Plateau in northwestern China, including plant roots and surface soil, were determined to investigate trends in δ15N variation of plant roots and soil along a precipitation and temperature gradient in northwestern China under the East Asian Monsoon climate condition. The δ15N values of surface soil from the study area vary from ?1.2‰ to 5.8‰, but from -5.1‰ to 1.9‰ in the plant roots. Our results indicate that (1) although the isotopic compositions of both plant roots and surface soil change with a similar trend along the climate gradient, the apparent nitrogen difference between plant roots and soil existed, with -δ15N values ranging from 0.3. to 7.2‰ with average of 4.1‰; and (2) mean annual precipitation (MAP) is the dominant factor for isotopic composition of plant-soil nitrogen in the Loess Plateau, and the δ15N values are less correlated with MAT; we suggest that nitrogen isotopic composition of soil is a potential tracer for environmental changes.

关键词：氮同位素物理性质化学性质环境论