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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, {3., Wuhan 43.072. China 2. graduate school of the{3.,{3., China) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. graduate school of the{2. 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 2. 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

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3. 1. Institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan, China 2. {3. University of chinese academy of sciences, {3. 100049, China 3. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, {3. 100101, China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China graduate University of chinese academy of sciences 100049 Beijing China Institute of Geographical sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 3. debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Effect of rock mass structure and block size on the slope stability——Physical modeling and discrete element simulation

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Science China(Technological sciences) 2005年第z1期48卷 1-17页

作者： LI Shihai1, LIAN Zhenzhong1,2.& J. G. Wang3.1. Institute of Mechanics, chinese academy of sciences, beijing 100080, China {2., chinese academy of sciences, beijing 100060, China 3. Tropical Marine Science Institute, National University of Singapore, Singapore 1192.0 chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.

Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

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Science China Earth sciences 2004年第8期47卷 710-719页

作者： FAN Chengxin1, ZHANG Lu1,2. QIN Boqiang1, WANG Sumin1, HU Weiping1 & ZHANG Chen1 1. Taihu Lake Laboratory for Ecosystem Research, Nanjing Institute of Geography & Limnology, chinese academy of sciences, Nanjing 2.0008, China {3. of chinese academy of sciences,{3., China 1. Taihu Lake Laboratory for Ecosystem Research Nanjing Institute of Geography & Limnology Chinese Academy of Sciences 210008 Nanjing China 2. graduate school of chinese academy of sciences 100039 Beijing China

Through man-made disturbance experiments, the corresponding relationships be-tween suspended particulate matter (SPM) and wind speed in different lake areas were simu-lated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show that about 0.44 t·a-1 loading in Lake Taihu mainly comes from phosphorus-releasing action of SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution mainly from biological mineralizing and decaying was about 42..8 t·a-1, which is equal to 15.0% of the total external loading of Lake Taihu, namely 4.7—7.5 times as much as SRP loading en-tering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

关键词： phosphorus release,wind wave disturbance,particulate decaying,dynamical loading,Lake Taihu.

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,{3., Shanghai 2.02.3. China {2. of the{3., beijing 100039, China 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological sciences,{3., Shanghai 2.003.0} China National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China graduate school of the{2. 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 12.69 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 2.% 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

Reconstruction of temperature series in China for the last 5000 years

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Progress in Natural Science:Materials International 2006年第8期16卷 838-845页

作者： GE Quansheng, WANG Shunbing and ZHENG Jingyun (Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, {2. 100101, China {3. school of the chinese academy of sciences, beijing 100039, China) [a]chinese academy of {2. Institute of Geographical Sciences and Natural Resources Research Beijing China [b]graduate school of the{2. Beijing China

A temperature series with a 100 year resolution for the last 5000 years in China has been reconstructed by using 3. longterm temperature proxy series selected from recent publications in the last 2. years. The proxy records include pollens, stalagmites, lake-sediments, peat, ice cores and historical documents. The result reveals that in the millennial scale temperature variation it was warm in 3.50-2.0 BC and it was cold in 2.0 BC-1950 AD. In the above two periods there were many stages of sub-scale temperature fluctuations. The result also shows an obvious temperature discrepancy on the century to multi-century scale between the Eastern Monsoon Region, the Qinghai-Tibet Region and the Northwestern Region in 2.50 BC, 2.50 BC, 13.0 BC, 950-3.0 BC, 50-2.0 AD, and 550 AD. A comparison between the reconstructed series of this paper and some North Hemisphere temperature series indicates that in the longterm scale change, the temperature change in China is in phrase with that of the Northern Hemisphere during the last 5000 years, while on the century to multi-century scale there are differences at the beginning and end times, which may imply that temperature change does not occur simultaneously in different regions.

关键词： temperature series the last 5000 years China.

The biomarkers of 2.6,10,15, 19-pentamethylicosenes and their carbon isotopic composition in the sediments from the Gulf of Mexico

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chinese Science Bulletin 2006年第14期51卷 1736-1740页

作者： SONG Zhiguang1,2.& WANG Cuiping1,3.. State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, China 2. Guangzhou Research Center of Gas Hydrate, chinese academy of sciences, Guangzhou 510640, China 3. {2. {3. of chinese academy of sciences, beijing 100039, China State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangzhou Research Center of Gas Hydrate Chinese Academy of Sciences Guangzhou 510640 China graduate school of{2. Beijing 100039 China

A group of 2.6,10,15,19-pentamethyli- cosenes (PMIΔ) containing 1―5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 2.8 *** PMIΔ compounds are distributed between nC2. and nC2. on the mass chromatogram of aliphatic fraction. Their δ 13. values are very much depleted in 13. and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13. values of companion n-alkanes range from ?2..4‰ to ?3..6‰. These unsaturated PMIΔ com-pounds are typical biomarkers derived from the an-aerobic oxidation of methane mediated by meth-ane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

关键词：生物标志墨西哥湾沉积物 PMIA 天然气水化物

Spatial heterogeneity of the driving forces of cropland change in China

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Science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2.3.1. Institute of Geographic sciences and Natural Resources Research,{3., {2. 100101, China {3. of the{3., beijing 100039, China 3. College of Arts and sciences of {2. Union University, {2. 100083. China 4. school of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL3.849, USA 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. graduate school of the chinese academy of sciences 100039 Beijing China 3. school of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of beijing Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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 2.0008, China 2. Institute of Tibetan Plateau Research, chinese academy of sciences, {2. 10085, China 3. {3. University of chinese academy of sciences, beijing 100039, China 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 100039 China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 2.0Pb 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. 2.0Pb 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, 2.0Pb 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 2.0Pb 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, 2.0Pb and 13.Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.