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Aridity/humidity status of land surface in china during the last three decades

Science china Earth sciences 2005年第9期48卷 1510-1518页

作者： WU Shaohong1, YIN Yunhe1,2, ZHENG Du1 & YANG Qinye1 1. Institute of Geographical sciences and Natural Resources Research, Chinese Academy of sciences (CAS), beijing 100101, china 2. graduate school of the CAS, beijing 100039, china 1. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences (CAS) 100101 Beijing China 2. graduate school of the CAS 100039 Beijing China

To clarify aridity/humidity status of land surface is helpful for studying environmental background and regional differences, seeking causes of environmental change, and providing a scientific basis for researches on climate change in the future. In this paper, the authors calcu- lated potential evapotranspiration of china using data from 616 meteorological stations during the period of 1971―2000 with the Penman-Monteith model recommanded by FAO in 1998. Vy- sothkii’s model was used to calculate aridity/humidity index. Then the calculated results of sta- tions were interpolated to land surface using ArcGIS. Results show that the annual average po- tential evapotranspiration is 400―1500 mm in the whole country, 600―800 mm in most parts of it; and 350―1400 mm in growing season (April―Octobor), which is nearly 200 mm less than the annual average. According to the aridity/humidity indexes of 1.0, 1.5 and 4.0, the aridity/humidity status is categorized to four types, namely, humid, subhumid, semiarid and arid. A majority of stations (76%) are more humid in growing season than the annual average. Results of com- prisons between the distribution map of aridity/humidity index with that of precipitation and vegetation indicate a good consistence of aridity/humidity status with natural environment. Therefore potential evapotranspiration calculated with modified FAO’s Penman-Monteith model in combination with aridity/humidity index that considers water balance can more reasonably explain the actual land surface aridity/humidity status of china.

关键词： potential evapotranspiration, aridity/humidity status, land surface, regional differences, Penman-Monteith.

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Overexpression of a tobacco small G protein gene NtRop1 causes salt sensitivity and hydrogen peroxide production in transgenic plants

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Science china(Life sciences) 2008年第5期51卷 383-390页

作者： CAO YangRong1,2, LI ZhiGang1,2, CHEN Tao1,2, ZHANG ZhiGang1, ZHANG JinSong1 & CHEN ShouYi1 1 National Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of sciences, beijing 100101, china 2 graduate school of Chinese Academy of sciences, beijing 100039, china 1. National Key Lab of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China 2. graduate school of Chinese Academy of sciences Beijing 100039 China

The small GTPases of Rop/Rho family is central regulators of important cellular processes in plants. Tobacco small G protein gene NtRop1 has been isolated; however, its roles in stress responses were unknown. In the present study, the genomic sequence of NtRop1 was cloned, which has seven exons and six introns, similar to the Rop gene structure from Arabidopsis. The NtRop1 gene was constitutively expressed in the different organs whereas the other six Rop genes from tobacco had differential expression patterns. The expression of the NtRop1 gene was moderately induced by methyl viologen, NaCl, and ACC treatments, but slightly inhibited by ABA treatment, with no significant induction by NAA treatment. The transgenic Arabidopsis plants overexpressing the NtRop1 showed increased salt sensitivity as can be seen from the reduced root growth and elevated relative electrolyte leakage. The hydrogen peroxide production was also promoted in the NtRop1-trangenic plants in comparison with wild type plants. These results imply that the NtRop1 may confer salt sensitivity through activation of H2O2 production during plant response to salt stress.

关键词： small G protein NtRop1 salt sensitive hydrogen peroxide

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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, china 2. Department of Geography, Nanjing University, Nanjing 210093, china 3. school of Earth sciences and Resources, china University of Geosciences, beijing 100083, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Nanjing University Nanjing 210093 China school of Earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

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Comparative study on CO_2 corrosion behavior of N80,P110,X52 and 13Cr pipe lines in simulated stratum water

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Science china(Technological sciences) 2010年第9期53卷 2342-2349页

作者： CAI YiDong1,GUO PengChao1,LIU DaMeng1,CHEN ShiYu2 & LIU JunLai3 1 school of Energy Resources,china University of Geosciences,beijing 100083,china 2 school of Materials Science and Engineering,University of Science and Technology beijing,beijing 100083,china 3 school of Earth sciences and Resources,china University of Geosciences,beijing 100083,china 1. school of Energy Resources China University of Geosciences Beijing 100083 China2. School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China3. School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

To better understand the carbon dioxide (CO2) corrosion behavior of carbon steel and its influence on petroleum development (including drilling,production and transportation) in the Daqing Oilfield,CO2 corrosion behaviors of N80,P110,X52 and 13Cr pipe lines in simulated solution at high temperature and high pressure condition are investigated by dynamic corrosion experiments,scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) *** show that the corrosion rate of all pipe lines increases quickly when CO2 partial pressure increases from 0.5 to 1.5 MPa,but it slows down when CO2 partial pressure further increases from 1.5 to 4.5 MPa,during which localized corrosion is *** the experimental temperature ranges from 60 to 120°C,localized corrosion *** corrosion rate of all pipe lines decreases sharply when the temperature changes from 60 to 100°C,and it becomes stable after the temperature is higher than 100°*** the flow rate is in the range of 0–1.5 m/s,the corrosion rate of sample X52 remains unchanged,but localized corrosion gradually becomes very serious when the flow rate further *** analyzing the corrosion product scales of sample 13Cr,some remarkable phenomena are *** the temperature range of 60–100°C,the corrosion product scales are loose and thick,but become very compact when the temperature increases above 100°*** the later case,localized corrosion is *** main components of the corrosion product scales are FeCO3 and Cr2O3.

关键词： CO2 corrosion pipe lines weight loss SEM EDS

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South china's Gondwana connection in the Paleozoic:Paleomagnetic evidence

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Progress in Natural Science:Materials International 2004年第1期14卷 86-91页

作者： ZHANG Shihong*(school of Earth sciences and Resources, china University of Geosciences, beijing 100083, china) china Univ Geosci Sch Earth Sci & Resources Beijing 100083 Peoples R China

The reconstruction in which the South china Block (SCB) lies along the Great India Australia region of Gondwana margin is tested by using existing Paleozoic paleomagnetic data. Under the proposed reconstruction, all six high quality paleopoles from the SCB between the Early Cambrian and late Early Devonian (～400 Ma) are in good agreement with coeval paleopoles from Gondwana. Thereafter, the apparent polar wander paths for the SCB and Gondwana diverge markedly. This indicates that the SCB had been part of Gondwana and the connection was intact from at least Early Cambrian until late Early Devonian, but they began to separate by late Middle Devonian (～375 Ma).

关键词： South china block Gondwana paleomagnetism reconstruction

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A formula on linear complexity of highest coordinate sequences from maximal periodic sequences over Galois rings

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Progress in Natural Science:Materials International 2006年第9期16卷 998-1001页

作者： HU Lei and SUN Nigang (State Key Laboratory of Information Security, graduate school of Chinese Academy of sciences, beijing 100049, china) [a]State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing China

Using a polynomial expression of the highest coordinate map, we deduce an exact formula on the linear complexity of the highest coordinate sequence derived from a maximal periodic sequence over an arbitrary Galois ring of characteristic p2 , where p is a prime. This generalizes the known result of Udaya and Siddiqi for the case that the Galois ring is Z4.

关键词： Galois ring highest coordinate sequence linear complexity.

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Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1,2, ZHENG Jinsong 1,2, XU Limei 1,2 and WANG Ding1*(1. Institute of Hydrobiology, Chinese Academy of sciences, Wuhan 430072, china 2. graduate school of the Chinese Academy of sciences, beijing 100039, china) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. graduate school of the Chinese Academy of sciences Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 23 individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage

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Linear EV model with replicate observations on independent variables

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Science china Mathematics 2006年第6期49卷 752-769页

作者： LIU Jixue, ZHANG Sanguo & CHEN Xiru Department of Statistics and Finance, University of Science and Technology of china, Hefei 230026, china Department of Mathematics, graduate school of Chinese Academy of sciences, beijing 100049, china 1. Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China 2. Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing 100049 China

This paper studies the linear EV model when replicate observations are made only on independent variables. We construct the estimates of regression coefficients and prove the consistency and asymptotic normality under some proper conditions. Results obtained reveal the difference between the case where the independent and dependent variables are observed repeatedly and simultaneously and the case studied in this article.

关键词： linear EV model, consistency, asymptotic normality.

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Sequence analysis of mRNA polyadenylation signals of rice genes

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Chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2, GAO Chenxi1,2,3 & HAN Bin1,3,41. National Center for Gene Research, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Shanghai 200233, china 2. graduate school of the Chinese Academy of sciences, beijing 100039, china 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Shanghai 200032, china National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China graduate school of the Chinese Academy of sciences Beijing 100039 China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3′-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12969 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953 genes. The al- ternative poly(A) sites were revealed in approxi- mately 25% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3′ fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3′ fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2. Department of Urban and Resources sciences, Nanjing University, Nanjing 210093, china 3. Department of Earth sciences, Nanjing University, Nanjing 210093, china 4. Department of Geography, Shaanxi Normal University, Xi’an 710062, china 5. Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 100029, china 6 Department of Geography, Qinghai Normal University, Xining 810008, china 7. graduate school of the Chinese Academy of sciences, beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. graduate school of the Chinese Academy of sciences Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of Earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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