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genetic structure and phylogeography of a relict tree fern,Sphaeropteris brunoniana (Cyatheaceae) from china and Laos inferred from cpDNA sequence variations:Implications for conservation

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Journal of Systematics and Evolution 2011年第1期49卷 72-79页

作者： 1.2 Zi-Juan WANG 1.Kai-Yun GUAN 1.(Kunming Institute of Botany, chinese academy of sciences, Kunming 650204,{1.) 2 (Graduate University of chinese academy of sciences, beijing 1.0049,{1.) (Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (Graduate University of chinese academy of sciences Beijing 100049 China)

In this study, we analyzed the genetic structure and phylogeography of Sphaeropteris brunoniana from china and Laos. Combining cpDNA trnL-trnF and atpB-rbcL sequence variations, five haplotypes were identi- fied from the 1. investigated populations. Moderate haplotype diversity (h = 0.66580) and low nucleotide diver- sity (π = 0.23 × 1. ?3 ) were detected. The S. brunoniana in Yunnan region had much higher genetic diversity (h = 0.601.5, π = 0.35 × 1. ?3 ) than that of Hainan–Laos (h = 0.00000, π = 0.00). A high level of genetic differentiation (94.74%) between the two regions was revealed by AMOVA. Nested clade analysis identified two major clusters of the five haplotypes, one clade in the Yunnan region and the other in Hainan–Laos. The analysis indicated that restricted gene flow with isolation by distance and allopatric fragmentation were likely the major processes that shaped the spatial distribution of the haplotypes. The isolated distribution of clades implied the emergence of independent refugia of this species in each region during Quaternary glaciations. The Yunnan populations frequently contained an ancestral haplotype, and most of them harbored other descendent haplotypes. Based on the distribution pattern of haplotypes and the nested clade analysis results, the Yunnan region potentially had several refugia of this species during glacial periods, whereas the Hainan populations were probable new colonizations.

关键词： atpB-rbcL Hainan–Laos phylogeography Sphaeropteris brunoniana trnL-trnF Yunnan.

Structures and physical properties of rigid polyurethane foams with water as the sole blowing agent

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Science china Chemistry 2006年第4期49卷 363-370页

作者： LI Xiaobin1.2, CAO Hongbin1.& ZHANG Yi1.1. Institute of Process Engineering, chinese academy of sciences, {1. 1.0080, china 2. Graduate School of the chinese academy of sciences, {1. 1.0039, china Institute of Process Engineering Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of sciences Beijing China

Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3365), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical charac- teristics, and the cream time and gel time were shorter for the fully water blown rigid foams than that for the fully cyclopentane blown foams. The density of foam samples decreased from 45.0 kg/m3 to 27.4 kg/m3 with the increase of water level from 3 pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 241.μm to 356 μm with the increase of water level from 3 pph to 7 pph, respectively. At the same time, poorer dimen- sional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2 out of the foam. The results of thermal analysis show that the glass transition temperature (Tg) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent.

关键词： polyether polyol, polyurethane rigid foam, compressive strength, dimensional stability, cell size, glass transition temperature.

ecological Behavior of Linear Alkylbenzene Sulfonate (LAS) in Soil-Plant Systems

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Pedosphere 2005年第2期15卷 216-224页

作者： JIALiang-Qing OUZi-Qing OUYANGZhi-Yun research{1.foreco-environmentalsciences ChineseAcademyofSciencesBeijing100085（China）／／AnhuiAcademyofEnvironmentalSciencesHefei230061（China） InstituteofAppliedecology ChineseAcademyofSciencesShenyang100016（China） research{1.foreco-environmentalsciences ChineseAcademyofSciencesBeijing100085（China）

More and more linear alkylbenzene sulfonate (LAS) has contaminated the water and soil ma pollution discharge, making it important to identify the {1.logical behavior and toxicity of LAS so as to carry out measures that will reduce its negative effects on the {1.system. The {1.logical behavior of LAS. including degradation, migration, and plant uptake, in both soil-paddy rice and soil-soybean systems was studied. Reduction of LAS in pot and field plots followed the first order reaction kinetics with degradation half-lives of 35-50 days with LAS decreasing to very low concentrations after a season of crop growth. Strong migration ability for LAS was found and the breakthrough time in a 1.5 in soil monolith was significantly shortened to 23 days by preferential flow. Leachate volumes of soil-paddy and soil-soybean systems at preferential breakthrough were much different, while the leachate volumes at equilibrium governed by soil adsorption/desorption processes were very similar. Significant uptake of LAS in both paddy rice and sovbeans was observed in pot and field experiments (P 1.and above of LAS significantly inhibited the growth of paddy seedlings (P 1.0 μg g-1. when higher, there was a strong negative influence, with decreases in height, spike length, and production, when lower than 80 μg g-1. paddy growth was stimulated. There was little effect of LAS on soybeans.

关键词： degradation ecological behavior linear alkylbenzene sulfonate migration preferential flow

^(40)Ar/^(39)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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Science china Earth {1. 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1. CHEN Wen2, 3 & YANG Nong1.1. Institute of geomechanics, {1. {1. of geological sciences, beijing 1.0081. china 2. Institute of geology, {1. {1. of geological sciences, beijing 1.0037, china 3. Institute of geology and geophysics,{1.}, beijing 1.0029, china Institute of geomechanics Chinese Academy of Geological Sciences Beijing China Institute of geology Chinese Academy of Geological Sciences Beijing China Institute of geology and geophysics Chinese Academy of Sciences Beijing China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (1.-1. Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 350℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/39Ar dating, late Cenozoic.

Effects of grassland degradation on chestnut soil properties in Bashang Plateau, china

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Journal of environmental {1. 2000年第1期12卷 105-109页

作者： SHENG Xue bin\+1. LIU Yun\|xia\+1. ZHAO Yu\|ping\+2 (1. research {1. for eco\|environmental sciences, chinese academy of sciences, beijing 100085, china 2. china University of Agriculture, beijing 1.0094, china)

The repeated effects of vulnerable habitat and unreasonable human activities on the Bashang Plateau of china led the chestnut soil to degrade. It expresses in reducing soil CEC, decreasing nutrient content, d{1.mposing organic complexes, and reducing humus in loose, steady and tight bond forms, respectively. The percentage of three forms are 21.—34%, 44%—55% and 5%—6.2%, respectively.

关键词： Bashang Plateau chestnut soil organic and inorganic complexes humus bond form CLC number: S1.2.4 Document code: A

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 266071.{1. 2. Graduate School, chinese academy of sciences, beijing 1.0039,{1.) Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 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 1.0° 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 2.21. 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.

Terrestrial transect study on driving mechanism of vegetation changes

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Science china Earth {1. 2008年第7期51卷 984-991页

作者： ZHANG YuJin1.2 & ZHOU GuangSheng1.1.State Key Laboratory of Vegetation and {1. Change, Institute of Botany,{1., beijing 1.0093, china 2 Graduate University of{1., beijing 1.0049, china State Key Laboratory of Vegetation and {1. Change Institute of Botany Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

In terms of chinese climate-ve{1.tation model based on the classification of plant functional types, to- {1.ther with climatic data from 1.51.to 1.80 and two future climatic scenarios (SRES-A2 and SRES-B2) in{1. from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of ve{1.tation types and their chan{1.s along the Northeast{1. Transect (NECT) and the North-South Transect of Eastern{1. (NSTEC) were simulated in order to understand the driving mechanisms of ve{1.tation chan{1.s under climatic chan{1.. The results indicated that the ve{1.tation distribution patterns would chan{1. significantly under future climate, and the major factors driving the ve{1.tation chan{1.s were water and heat. However, the responses of various ve{1.tation types to the chan{1.s in water and heat factors were obviously different. The ve{1.tation chan{1.s were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect ve{1.tation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium

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Science china Earth {1. 2005年第4期48卷 521-529页

作者： LIU Xiaohong1.2, QIN Dahe1. SHAO Xuemei , CHEN Tuo1.& REN Jiawen1. 1. Cold and Arid Regions environmental and Engineering {1. Institute, chinese academy of sciences, Lanzhou 730000, china 2. Institute of geographical sciences and Natural Resources {1., chinese academy of sciences, beijing 1.01.1. china Cold and Arid Regions environmental and Engineering {1. Institute Chinese Academy of Sciences Lanzhou China Institute of geographical {1. and Natural Resources {1. Chinese Academy of Sciences Beijing China

Based on the cross-dated tree-ring samples collected from the middle Qilian Moun- tain, a standard ring-width chronology had been developed, which covered the period AD 1.00 to 2000. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the “Little Ice Age” and the con- tinuous warming during the twentieth century. Comparison between the ring-width chronology and δ1.O records from the Dunde ice core in the Qilian Mountain indicated that there was a con- sistent trend in both time series. A significant correlation existed between our ring-width chro- nology and the Northern Hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global cli- mate.

关键词： middle Qilian Mountain, tree-ring width chronology, temperature variations.

An evaluation of mercury emissions from the chlor-alkali industry in china

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Journal of environmental {1. 2000年第S1期12卷 24-30页

作者： QI Xiao\|fan 1, LIN Yu\|huan\+1, CHEN Jian\|hua\+1, YE You\|zhong 2 (1. research {1. for eco environmental sciences, chinese academy of sciences, beijing 100085, china 2. china National Chemical Information {1., beijing 100029, china)

The present status and the history of chlor alkali industry using mercury as cathode in china has been studied. Quantitative mercury emission has been estimated. At present, 1..5%—20% of the consumed mercury is released into water, 49.1.—53.3% of the Hg is dischar{1.d to the brine system outside the plants. 1.%—1.% of the Hg is emitted directly to the atmosphere, 5 3%—6 7% enters waste materials. The chlor alkali industry in china dischar{1.d about 1. tons every year. The total amount of mercury released by the chlor alkali industry in china is estimated to be 1.00—2700 tons since 50's. With the result of improved technology and more strict environmental regulations started in late 1.70's, chlorine plants reduced their mercury loss factor from 0 5? ? 4 kg/t NaOH before 1.77 to 0.1.—0.1. kg/t NaOH in 1.97. The number of mercury cells in alkali plants was also reduced. In 1.98, china is planning to finish the history of producing chlorine and caustic soda using the mercury cell process in the near future. How to deal with the emitted mercury will remain a main problem.

关键词： chlorine alkali industry Hg cell Hg loss factor quantity of the discharged mercury