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Carbon isotope ratios of C_(4. plants in loess areas of North china

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Science china Earth sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2.3, HAN Jiamao 2. ZHOU Liping3, XIONG Xiaogang4. TAN Ming2. WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, china Agricultural University, Beijing 100094. china 2. institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002., china 3. College of Environmental sciences, MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, china 4. institute of botany, chinese academy of sciences, Beijing 100093. china 5. Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712.00, china 6. Network Center, china Agricultural University, Beijing 100094. china 1. Department of Plant Nutrition China Agricultural University Beijing 100094 China 2. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. College of Environmental sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. institute of botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China 6. Network Center China Agricultural University Beijing 100094 China

Carbon isotope ratios (δ^(13)C) of 89 C_4.plant samples were determined fromthe loess area in North china. δ^(13)C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13)C values of C_4.plants show a slight decreasingtrend. The δ^(13)C values of C_4.plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3 species.

关键词： C4 plants, carbon isotope ratios, loess area.

Wind vector retrieval using dual polarization imagery of ASAR

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Progress in Natural Science:Materials International 2006年第11期16卷 1183-1187页

作者： SONG Guiting~ 1,2., HOU Yijun~1** and QI Peng~1(1. institute of Oceanology, chinese academy of sciences, Qingdao 2.6071, {2. 2. Graduate School, chinese academy of sciences, Beijing 100039, {2.) [a]institute of Oceanology Chinese Academy of Science Qingdao China [b]Graduate School Chinese Academy of Sciences Beijing China

A new algorithm for retrieving wind vector using dual polarization imagery of advanced synthetic aperture radar (ASAR) is developed and tested. Based on the combination of co-polarization and cross-polarization, this new algorithm effectively eliminates the 180° ambiguity which occurs when using single imagery of the ASAR to retrieve wind vector. This algorithm also solves the problem that the retrieval results will break down on very small spatial scales. The results retrieved from dual polarization imagery of ASAR show that the wind speed and direction are in agreement with the data from Quikscat and buoy measurements. The root mean square errors of wind direction and speed between the retrieved results and data from Quikscat are 2.2.° and 0.53 m/s, respectively. Comparisons between the new method and the traditional method show that the new methods fit the buoy data and Quikscat data a little better than the traditional method in this image.

关键词： wind vector retrieval ASAR dual polarization.

Toward a general evaluation model for soil respiration (GEMSR)

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Science china(Life sciences) 2008年第3期51卷 254-262页

作者： ZHOU GuangSheng, JIA BingRui, HAN GuangXuan & ZHOU Li Key Laboratory of Vegetation and Environmental Change, institute of botany,{2., Beijing 100093. {4. Key Laboratory of Vegetation Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Soil respiration is an important component of terrestrial carbon budget. Its accurate evaluation is es- sential to the study of terrestrial carbon source/sink. Studies on soil respiration at present mostly focus on the temporal variations and the controlling factors of soil respiration, but its spatial variations and controlling factors draw less attention. Moreover, the evaluation models for soil respiration at present include only the effects of water and heat factors, while the biological and soil factors controlling soil respiration and their interactions with water and heat factors have not been considered yet. These models are not able to accurately evaluate soil respiration in different vegetation/terrestrial ecosystems at different temporal and spatial scales. Thus, a general evaluation model for soil respiration (GEMSR) including the interacting meteorological (water and heat factors), soil nutrient and biological factors is suggested in this paper, and the basic procedure developing GEMSR and the research tasks of soil respiration in the future are also discussed.

关键词： soil respiration controlling factors general evaluation model

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 {2.0072. 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 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

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. institute of Engineering Thermophysics, chinese academy of sciences, Beijing 100080, {2. 2. Graduate School, chinese academy of sciences, Beijing 100080, {2. 1. institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. Graduate School Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Climate instability in the Yili region, Xinjiang during the last glaciation

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chinese Science Bulletin 2000年第17期45卷 1604-1609页

作者： YE Wei, DONG Guangrong, YUAN Yujiang & MA Yingjie1. Xinjiang institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, {2. 2. Department of Geography, Zhejiang Normal University, Jinhua 32.004. {2. 3. institute of Desert Research, chinese academy of sciences, Lanzhou 730000, {2. 4. Xinjiang institute of Meteorological Research, Urumqi 830002. {2. Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Department of Geography Zhejiang Normal University Jinhua China institute of Desert Research Chinese Academy of Sciences Lanzhou China Xinjiang institute of Meteorological Research Urumqi China

The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the Xinjiang Uygur Autonomous Region. Through the study of the loess section with a thickness of 2..5 m, much useful information about climatic change in this region during the last glaciation was gotten. Grain size analysis of loess samples in the section showed that the climatic change in the Yili region was of instability during the last glaciation and similar to those of the North Atlantic Ocean and Greenland. In correspondence with the Heinrich events, the percentage of the size fraction of loess with grain size less than 10 μm decreased in cold stadials in the Yili region. This result suggests that the westerly wind be strengthened during the cold periods. Compared with the stadials, the content of the loess with grain size less than 10 μm was increased in interstadials, which indicated that the strength of the westerly wind was weakened. It is obvious that the climate was instable

关键词： Yili region last glaciation climate instability.

Phylogenetic studies of the core Alismatales inferred from morphology and rbcL sequences

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Progress in Natural Science:Materials International 2009年第8期19卷 931-945页

作者： Xiaoxian Li, Zhekun Zhou Kunming institute of botany,{2., Kunming 6502.4. china [a]Kunming institute of botany Chinese Academy of Sciences Kunming 650204 China

The phylogeny of Alismatales remains an area of deep uncertainty, with different arrangements being found in studies that examined various subsets of genes and taxa. Herein we conducted separate and combined analyses of 103 morphological characters and 52.rbcL sequences to explore the controversial phylogenies of the families. Congruence between the two data sets was explored by computing several indices. Morphological data sets contain poor phylogenetic signals. The homology of morphological characters was tested based on the total evidence of phylogeny. The incongruence between DNA and morphological results; the hypothesis of the ‘Cymodoceaceae complex’; the relationships between Najadaceae and Hydrocharitaceae; the intergeneric relationships of Hydrocharitaceae; and the evo- lutionary convergence of morphological characters were analyzed and discussed.

关键词： Alismatales Morphological phylogeny rbcL sequences Cymodoceaceae complex Najadaceae Hydrocharitaceae

U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science china Earth sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1, HU Jianmin2. SONG Biao3,4. CHEN Mulun1, XIE Shengzhou1 & FAN Yuan1 1. Geological Surveying institute of Hainan, Haikou 5702.6, {2. 2. institute of Geomechanics, chinese {4. of Geological sciences, Beijing 100081, {2. 3. Beijing Center of SHRIMP, Beijing 100037, {2. 4. institute of Geology, chinese {4. of Geological sciences, Beijing 100037, {2. 1. Geological Surveying institute of Hainan 570206 Haikou China 2. institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 3. Beijing Center of SHRIMP 100037 Beijing China 4. institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the Beijing Ion-probe Center, acquire 2.6Pb/2.8U ages of 368±3.5 Ma (of granite, 95% confidence level, MSDW=1.2.) and 362.9±6.1 Ma (of gneiss, 95% confidence level, MSDW = 2.04. respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon SHRIMP U-Pb dating.

Fluxes of CO_2. N_2. and CH_4.from a typical temperate grassland in Inner Mongolia and its daily variation

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chinese Science Bulletin 2000年第17期45卷 1590-1594页

作者： DONG Yunshe, ZHANG Shen, Ql Yuchun, CHEN Zuozhong & GENG Yuanbo1. institute of Geography, chinese academy of sciences, Beijing 100101, {2.:2. institute of {4., chinese academy of sciences, Beijing 100093. {2. Correspondence should be addressed to Dong Yunshe institute of Geography Chinese Academy of Sciences Beijing China institute of botany Chinese Academy of Sciences Beijing China

Using a dark enclosed chamber technique, the fluxes of CO2. N2. and CH4.from nature and disturbed grassland were measured on the spot in Inner Mongolian Temperate Grassland along the annual rainfall gradient section ranging from 4.0 to 2.0 mm. The results showed that the measured mean fluxes of CO2. N2. and CH4.ere (1 180.4.±308.7), (0.010 ± 0.004. and (-0.039 ± 0.016) mg · m-2.h, respectively. The decrease of the fluxes of CO2. N2. and CH4.follows with that of annual rainfall gradient in the measurement area. Human activities, such as grazing and reclamation are also critical factors to affect the fluxes of these gases from grassland. Daily continuous measurement of CO2. N2. and CH4.fluxes showed a strong diurnal variation with higher emission in the daytime. A good relationship between the fluxes of CO2. N2., CH4.and temperature was exposed in this study.

关键词： Northeast china Transect (NECT) temperate grassland greenhouse gas flux.