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Using the dual isotopes approach to identify the nitrate sources of karst groundwater, guiyang, Southwest china.

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Acta Geochimica 2006年第S1期 173-174页

作者： Siliang LI, Congqiang LIU, Yunchao LANG The state key laboratory of environmental geochemistry, institute of geochemistry, chinese academy of sciences, guiyang 550002, china

Applications of synchrotron-based X-ray techniques in environmental science

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Science china Chemistry 2010年第12期53卷 2529-2538页

作者： LUO Lei & ZHANG ShuZhen state key laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-environmental sciences,chinese academy of sciences,Beijing 100085,china state key laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-environmental sciences Chinese Academy of Sciences Beijing China

Synchrotron-based X-ray techniques have been widely applied to the fields of environmental science due to their element-specific and nondestructive properties and unique spectral and spatial resolution *** techniques are capable of in situ investigating chemical speciation,microstructure and mapping of elements in question at the molecular or nanometer scale,and thus provide direct evidence for reaction mechanisms for various environmental *** this contribution,the applications of three types of the techniques commonly used in the fields of environmental research are reviewed,namely X-ray absorption spectroscopy (XAS),X-ray fluorescence (XRF) spectroscopy and scanning transmission X-ray microscopy (STXM).In particular,the recent advances of the techniques in china are elaborated,and a selection of the applied examples are provided in the field of environmental ***,the perspectives of synchrotron-based X-ray techniques are *** their great progress and wide application,the techniques have revolutionized our understanding of significant geo-and bio-chemical *** is anticipatable that synchrotron-based X-ray techniques will continue to play a significant role in the fields and significant advances will be obtained in decades ahead.

关键词： synchrotron spectroscopy spectromicroscopy environmental science

In situ DRIFTS study of hygroscopic behavior of mineral aerosol

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Journal of environmental sciences 2010年第4期22卷 555-560页

作者： Qingxin Ma,Hong He,Yongchun Liu state key laboratory of environmental Chemistry and Ecotoxicology,Research Center for Eco-environmental sciences,chinese academy of sciences,Beijing 100085,china. state key laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

In situ diffusion reflectance infrared Fourier transform spectroscopy was used to study the water adsorption on mineral oxides （SiO2, a-Al2O3, MgO, Fe2O3, TiO2）. The results showed that all the water adsorption isotherms were well fitted with the Brunauer-Emmett-Teller （BET）-Ⅲ type equation, with the calculated monolayers occurring at 24%-30% relative humidity. It showed that about 1-5 layers of water adsorbed on oxides surfaces in ambient relative humidity （20%-90%）. The measured deliquescence relative humidity of NaCl was （74 ± 1）%, which demonstrated that DRIFTS is a useful method for the study the hygroscopic behavior of mineral dust. In addition, the limits of DRIPTS were also discussed.

关键词： DRIFTS mineral oxides water adsorption hygroscopicity

Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in china

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2,3 Sheng-Bin CHEN § 1 Gao-Ming JIANG 3 Zhi-Yun OUYANG 3 Wei-Hua XU 3 Yi XIAO 1 (state key laboratory of Vegetation and environmental Change, institute of Botany, chinese academy of sciences, Beijing 100093, china) 2 (Graduate University of the chinese academy of sciences, Beijing 100049, china) 3 (state key laboratory of Urban and Regional Ecology, Research Center for Eco-environmental sciences, chinese academy of sciences, Beijing 100085, china) (state key laboratory of Vegetation and environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (state key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China)

environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from china, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

Effect of temperature on the sorption and desorption of perfluorooctane sulfonate on humic acid

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Journal of environmental sciences 2010年第3期22卷 355-361页

作者： Chengxia Jia, Chun You, Gang Pan state key laboratory of environmental Aquatic Chemistry, Research Center for Eco-environmental sciences, chinese academy of sciences, Beijing 100085, china. state key laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Sorption and desorption of perfluorooctane sulfonate （PFOS） on humic acid at different temperatures were studied. It was found that the sorption process could be modeled with power kinetic equation very well, suggesting that diflusion predominated the sorption of PFOS on the humic acid. The sorption capacity was doubled when the temperature increased from 5 to 35°C, and thermodynamics parameters △G0 was calculated to be –7.11 to –5.04 kJ/mol, △H0 was 14.2 kJ/mol, and △S 0 was 69.5 J/（mol·K）, indicating that the sorption was a spontaneous, endothermic, and entropy driven process. Desorption hysteresis occurred at all studied temperatures which suggested that humic acid may be an important sink of PFOS in the environment.

关键词： perfluorooctane sulfonate sorption desorption temperature humic acid

Combined fluorescence and electrochemical investigation on the binding interaction between organic acid and human serum albumin

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Journal of environmental sciences 2009年第3期21卷 373-379页

作者： CHEN Yan-Min,GUO Liang-Hong state key laboratory of environmental Chemistry and Ecotoxicology,Research Center for Eco-environmental sciences,chinese academy of sciences,Beijing 100085,china. state key laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Human serum albumin （HSA） is a plasma protein responsible for the binding and transport of fatty acids and a variety of exogenous chemicals such as drugs and environmental pollutants. Such binding plays a crucial role in determining the ADME （absorption, distribution, metabolism, and excretion） and bioavailability of the pollutants. The binding interaction between HSA and acetic acid （C2）, octanoic acid （C8） and dodecanoic acid （C12） has been investigated by the combination of site-specific fluorescent probe, tryptophan intrinsic fluorescence and tyrosine electrochemistry. For the study of the fatty acid interaction with the two drug-binding sites on HSA, two fluorescent probes, dansylamide and dansyl-L-proline were employed in the displacement measurements. Intrinsic fluorescence of tryptophan in HSA was monitored upon addition of the fatty acids into HSA. Electrocatalyzed response of the tyrosine residues in HSA by a redox mediator was used to investigate the binding interaction. Qualitatively, observations from these three approaches were very similar. HSA did not show any change in the fluorescence and electrochemical experiments after mixing with C2, suggesting there is no significant interaction with the short-chain fatty acid. For C8, the measured signal dropped in a single-exponential mode, indicating an independent and non-cooperative binding. The calculated association constant and binding ratio were 3.1 × 10^6 L/mol and 1 with drug binding Site Ⅰ, 1.1 × 107 L/mol and 1 with Site Ⅱ, and 7.0× 0^4 L/mol and 4 with the tryptophan site, respectively. The measurements with C12 displayed multiple phases of fluorescence change, suggesting cooperativity and allosteric effect of the C12 binding. These results correlate well with those obtained by the established methods, and validate the new approach as a viable tool to study the interactions of environmental pollutants with biological molecules.

关键词： absorption, distribution, metabolism, and excretion (ADME) organic acid human serum albumin fluorescence electrochemistry

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, guiyang 550003, china 2. Nanjing institute of Geology and Palaeontology, chinese academy of sciences, Nanjing 210008, china 3. state key laboratory of Papaeobiology and Stratigraphy, Nanjing institute of Geology and Palaeontology, Nanjing 210008, china 4. Department of Geological Science, Ohio state University, Columbus, OH 43210, USA 5. institute of geochemistry, chinese academy of sciences, guiyang 550002, china) College of Resource and Environment of Guizhou University Guiyang 550003 China Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China state key laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, china and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 1934, are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou china.

Carbon Storage and Vertical Distribution in Three Shrubland Communities in Gurbantünggüt Desert,Uygur AutonomousRegion of Xinjiang,Northwest china

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chinese Geographical Science 2012年第5期22卷 541-549页

作者： GONG Yanming 1 ,HU Yukun 1 ,FANG Fei 1 ,LIU Yanyan 1 ,LI Kaihui 1 ,ZHANG Guangming 2 (1.key laboratory of Biogeography and Bioresource in Arid Land,Xinjiang institute of Ecology and Geography,chinese academy of sciences,Urumqi 830011,china 2.state key laboratory of Vegetation and environmental Change, institute of Botany,chinese academy of sciences,Beijing 100093,china) key laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China state key laboratory of Vegetation and environmental Change Institute of Botany Chinese Academy of Sciences Beijing China

This study was carried out in the Gurbantünggüt Desert,Uygur Autonomous Region of Xinjiang,Northwest china in August,*** quantify the storage,contribution and vertical distribution patterns of plant biomass carbon (PBC)and soil organic carbon(SOC)in the study area,we investigated the carbon concentrations and its vertical distribution in three different desert shrubland communities dominated by Reaumuria soongorica,Haloxylon ammodendron+*** and Tamarix ramosissima+***,*** analyzed vertical distribution of root biomass carbon and soil carbon contents by excavating soil profiles for each dominated *** results show that SOC is considerably the larger carbon pool in the soil layers of 1.0-3.0 m(the mean value of three shrubland communities is 38.46%)and 3.0-5.0 m(the mean value is 40.24%).In contrast,70.74%of belowground biomass carbon storage in 0-1.0 m layer,and its content decrease with increasing soil *** Haloxylon ammodendron+R. soongorica shrubland community has the highest belowground biomass carbon among three selected communities. This study highlights the importance of SOC stored in deep soil layers(lower than 3.0 m from the surface)in arid shrubland communities in the global carbon *** addition,it provides the data support for revealing deep soil solid carbon potential,and offers scientific basis for the further research in the carbon cycle of terrestrial ecosystem.

关键词： shrubland community plant biomass carbon soil organic carbon vertical distribution Gurbantünggüt desert

Responses of differences in iron and manganese partitioning patterns within and among organs on legume biomass in limestone and sandstone areas

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Acta Geochimica 2006年第S1期 169-170页

作者： Hechun PIAO, Congqiang LIU The state key laboratory of environmental geochemistry, chinese academy of sciences, guiyang 550002, china