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Source characteristics of O_3 and CO_2 at Mt. Waliguan Observatory,Tibetan Plateau implied by using ~7Be and ^(210)Pb

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Science China Earth Sciences 2011年第4期54卷 550-560页

作者： ZHENG XiangDong wan guojiang TANG Jie Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological Sciences Beijing 100081 China State Key Laboratory of Environment Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

The weekly averages of near-surface ^7Be, ^210pb, 03, and CO2 concentrations at the Global Atmospheric Watch Observatory, Mt. Waliguan （101.98°E, 36.287°N, 3810 m a.s.l.）, from October 2002 to January 2004 are presented. With the establishment of the new datasets of DCCW （Differential Concentrations in Contiguous Weeks） of ^7Be,^210pb, and O3, CO2 （△^7Be, △^210pb, △O3, △CO2, respectively, the impacts of upper-level downward transports and land-surface emissions on O3 and CO2 concentrations are implied by ^7Be and ^210pb being as independent tracers. The relations among △^7Be, △^210pb, and △O3, △CO2 are examined statistically and compared. The results indicate that with the DCCWs, the interferences with the tracing significance of ^7Be and ^210Pb from the seasonal wet scavenging of atmospheric aerosol are greatly reduced, and the weighting sources of O3 or CO2 variations are more pronounced. Basically, the variability of surface O3 is controlled predominately by air mass transported from the upper atmosphere levels while the emission from the Continent Boundary Layer （CBL） has an obvious input for CO2. The relation between △^210pb and △O3 reflects that influences of CBL emission are generally positive/negative for surface O3 budget in summer/winter, and the relation of △^7Be and △CO2 also reveals that upper level downward transport has positive/negative inputs for CO2 in summer/winter. With the highly correlated relations between ^7Be and O3, a quantitative estimation is made of the stratospheric contributions to the budget of surface O3 at WLG： the monthly averages of stratospheric O3 range from 6 ×10^-9 to 8 ×10^-9 （volume mixing ratio） in April and from June to August, and 2 ×10^-9 to 4 ×10^-9 in the remaining months. For the ultimate sources of the baseline concentration of surface 03, which consist of only stratospheric transport and tropospheric photochemistry production, the contribution from stratospheric transport is estimated to be about 20 ×10^-9 from May

关键词： Differential Concentrations in Contiguous Weeks (DCCW) Continent Boundary Layer (CBL) emission downward transport from stratosphere natural trace WLG

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Tree-Ring Carbon Isotopic Constraints on Carbon-Water Exchanges between Atmosphere and Biosphere in Drought Regions in Northwestern China

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 301-305页

作者： wanG Shilu wan guojiang State Key Laboratory of Environmental Geochemistry Institute of GeochemistryCASGuiyang 550002

The comparison between the carbon isotope and the index of ring width of a pine disc from the Tuomuer Peak region in Xinjiang shows that the effects of climate changes on the tree-ring growth and carbon isotopic fractionation varies with time. The reason is probably relative to the characters of climate changes and adaptability of the tree-ring growth to climate changes. The relationships between the atmospheric CO2 level and the revised δ13Cair by the tree-ring carbon isotope indicate that the carbon cycle is not in a steady state, but under a stage-change condition in this area. It also can be concluded that the ratio of CO2 from the terrestrial eco-system has increased, and the flux of CO2 exchange between the atmosphere and the biosphere was gradually increasing over the past century. In addition, the results also confirm the validity and superiority of the carbon isotope to the research of the water-use efficiency.

关键词： tree ring carbon isotope CO_(2) exchange water-use efficiency

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Different fossil brachiopod skeletal microstructure of different information on carbon and oxygen isotope contents

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Chinese Science Bulletin 1999年第22期44卷 2087-2094页

作者： Xinqing Li guojiang wan Ronggui Huang Chinese Acad Sci Inst Geochem State Key Lab Environm Geochem Guiyang 550002 Peoples R China Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Whether there is isotope fractionation caused by metabolism (vital effect) of bra-chiopods in geologic time with their shells’ δ18O and δ13C has been studied intensively in the field of carbonate isotope geochemistry in the last decade. The approach to dealing with the problem is by comparing isotopic compositions between different fossil brachiopods with their secondary shells which usually consist of two kinds of layers: prismatic layer composed of pris-

关键词： fossil brachiopod geochemistry stable isotope Longmenshan.

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Atmospheric pollutants transport tracks revealed from ^(131)I, ^(137)Cs, and ^(134)Cs leaked from Fukushima accident and ~7Be and ^(210)Pb observed at Guiyang of China

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Chinese Journal Of Geochemistry 2014年第3期33卷 248-255页

作者： wan Enyuan ZHENG Xiangdong wanG Shilu wan guojiang wanG Changsheng State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological Sciences

A massive earthquake measuring 9.0 on the Richter scale that occurred on March 11, 2011, on Honshu Island, Japan, caused radioactivity leakage from the Fukushima Nuclear Power Plant, which led to the leakage of artificial nuclides(131I, 137 Cs, and 134Cs) and their global transportation by atmospheric circulation. This paper reports a systematic comparative observation on radioactive concentrations of natural nuclides(7Be and 210Pb) and artificial nuclides(131I, 137 Cs, and 134Cs) at the surface level, measured in weekly continuous aerosol sampling at Mount Guanfeng, Guiyang, China, from March 17, 2011 to April 28, 2011. During this period, the variations in the nuclide concentrations associated with their transport paths were analyzed with 315 hour back-trajectories of air mass initialized 500 m above the surface level at Guiyang. The results show that the pollutants of nuclear leakage from the Fukushima accident were transported to the Guiyang region of China via two significant pathways. In the first pathway the first wave of nuclear pollutants were transported from west to east in air masses at higher altitudes via global atmospheric circulation. The nuclear pollutants encircled the Earth almost once and after about 10 days to two weeks, between March 24 and March 31, 2011, intruded Guiyang from the northwestern region of China. In the second pathway, the nuclear pollutants from the Fukushima region arrived at Guiyang between April 7 and April 14, 2011, via air masses at lower altitudes that moved southwards because of the squeezing of the northeast Asian weather system and then by the influence, in succession, of the northeastern and southeastern air currents in the low-latitude region. The first transport pathway for atmospheric pollutants is on a global scale and based on air masses at higher altitudes, and the second transport pathway is on an eastern Asia regional scale and based on the air masses at lower altitude.

关键词：全球大气环流 137Cs 贵阳地区铅-210 污染物输送中国活度事故

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Mass and isotopic concentrations of water-insoluble refractory carbon in total suspended particulates at *** Observatory(China)

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Particuology 2015年第3期13卷 24-31页

作者： Xiangdong Zheng Chengde Shen guojiang wan Jie Tang Kexin Liu Key Laboratory of Atmospheric Chemistry Chinese Academy of Meteorological Sciences State Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences State Key Laboratory of Environment Geochemistry Institute of GeochemistryChinese Academy of Sciences Center of Meteorological Sounding Chinese Meteorological Administration State Key Laboratory of Nuclear Physics and Technology and Institute of Heavy Ion Physics Peking University

Mass concentration and isotopic values δ13C and 14C are presented for the water-insoluble refractory carbon （WIRC） component of total suspended particulates （TSP）, collected weekly during 2003, as well as from October 2005 to May 2006 at the WMO-GAW Mt. Waliguan （WLG） site. The overall average WlRC mass concentration was （1183 ± 120）ng/m3 （n = 79）, while seasonal averages were 2081 ± 1707 （spring）, 454±205 （summer）, 650 ±411 （autumn）, and 1019 ± 703 （winter） ng/m3. Seasonal variations in WIRC mass concentrations were consistent with black carbon measurements from an aethalometer, although WIRC concentrations were typically higher, especially in winter and spring. The δ13C PDB value （-25.3 ± 0.8）%0 determined for WIRC suggests that its sources are C3 biomass or fossil fuel combustion. No seasonal change in δ13C PDB was evident. The average percent Modern Carbon （pMC） for 14C in WIRC for winter and spring was （67.2 ± 7.7）% （n = 29）. Lower pMC values were associated with air masses trans- ported from the area east of WLG, while higher pMC values were associated with air masses from the Tibetan Plateau, southwest of WLG. Elevated pMC values with abnormally high mass concentrations of TSP and WIRC were measured during a dust storm event.

关键词： Water-insoluble refractory carbon (WIRC)Mass concentration813C14CMt. Waliguan (WLG)

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Sodic metasomatism in a dacite weathering profile in Pinxiang, Guangxi, China

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Chinese Journal Of Geochemistry 2007年第4期26卷 434-438页

作者： GU Shangyi wan guojiang MAO Jianquan Key Laboratory of Karst Environment and Geohazard Prevention （Guizhou University） Ministry of Education Guiyang 550003 China School of Resources and Environmental Engineering Guizhou University Guiyang 550003 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

The Pinxiang weathering profile is well developed on Early Triassic dacite lavas of the Baisi Formation. At the top of the profile is developed a red clay zone which is characterized mineralogically by kaolinite, iron oxide minerals, quartz, and a small amount of illite, montmorillonite and vermiculite. In going downwards the red clay zone gives way to a saprolite zone in which plagioclase pseudomorphs have been well preserved although replaced by kaolinite. Beneath the saprolite zone is the saprock zone characterized by less weathering for dacite. At the bottom of the weathering profile is the parent material, dacite, which is composed mainly of plagioclase, quartz, K-feldspar and biotite which have been largely altered into chlorite owing to submarine extrusion of dacite lavas. Some layers in the weathering profile show obvious sodium enrichment and potassium depletion relative to others. In the Al2O3-(CaO*+Na2O)-K2O triangular diagram, the weathering trends of these layers in the middle stage are remarkably deviated from normal ones. Both mineralogy and micro-morphology of these layers indicate such deviation resulted from sodic metasomatism of orthoclase.

关键词：英安岩化学风化交代作用中国

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Carbon-Doped Titanium Oxide Films by DC Reactive Magnetron Sputtering Using CO_2 and O_2 as Reactive Gas

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Acta Metallurgica Sinica(English Letters) 2014年第2期27卷 239-244页

作者： Dong Xie Feng Wen Wenmao Yang Xueyuan Li Yongxiang Leng guojiang wan Hong Sun Nan Huang School of Physical Science and Technology Southwest Jiaotong University Key Laboratory for Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong University Key Laboratory of Tropical Biological Resource of Chinese Educational Ministry School of Materials and Chemical EngineeringHainan University Institute of Mechanical Manufacturing Technology China Academy of Engineering Physics

CO2 and O2 were employed as reactive gases to fabricate carbon-doped titanium oxide films using DC reactive magnetron sputtering. Microstructure, composition and optical band gap of the films were investigated by X-ray diffraction, X-ray photoelectron spectroscopy, and UV-visible spectrophotometer, respectively. The results showed that carbon-doped titanium monoxide films （C-TiO） with a carbon concentration of 5.8 at.% were obtained in an AffCO2 mixed atmosphere. However, carbon-doped futile and anatase （C-TiO2） with a carbon concentration of about 1.4 at.% were obtained in an Ar/CO2/O2 mixed atmosphere. The optical band gaps of C-TiO and C-TiO2 were about 2.6 and 2.9 eV, respectively. Both of them were narrower than that of pure TiO2 films. Films with narrowed optical band gap energy are promising in promoting their photo-catalytic activity.

关键词： Carbon-doped titanium oxide films Optical band gap DC reactive magnetron sputtering

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^(10)Be/~7Be implies the contribution of stratosphere-troposphere transport to the winter-spring surface O_3 variation observed on the Tibetan Plateau

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Chinese Science Bulletin 2011年第1期56卷 84-88页

作者： ZHENG XiangDong SHEN ChengDe wan guojiang LIU KeXin TANG Jie XU XiaoBin Chinese Academy of Meteorological Sciences Beijing 100081 China Key Laboratory oflsotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China State Key Laboratory of Environment Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China State Key laboratory of Nuclear Physics and Technology & Institute of Heavy Ion Physics Peking University Beijing 100871 China

10Be/7Be is a stratospheric sensitive *** this paper,measurements of 10Be/7Be and surface O3 from October 2005 to May 2006 at *** (hereafter WLG,100.898°E,39.287°N,3810 m,a.s.l.),China global atmospheric watch (GAW) observatory,are introduced and used to investigate the stratosphere-troposphere transport (STT) and its impact on surface O3 on the Tibetan *** results show that the magnitude of STT is weak in winter,followed by strengthening from the end of winter to the middle of spring (from mid February to mid April) with large increases in 10Be,7Be,10Be/7Be and surface *** the end of spring (from the end of April to mid May in this paper),the STT weakened,and the continuous increase of surface O3 at WLG is produced by tropospheric photochemistry reactions.

关键词：臭氧变化青藏高原平流层对流层地表运输冬春季表面测量

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Characteristics of U-pattern distribution of high-concentration ^(210)Pb in surface air at central Guizhou,China

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Chinese Science Bulletin 2005年第16期50卷 1750-1755页

作者： wan guojiang YANG Wei wanG Shilu wan Enyuan WU Fengchang S.N.LEE wanG Changsheng HUANG Ronggui State Key Laboratory of Environmental Geochemistry ChineseAcademy of Sciences Guiyang 550002 China Environmental Measurements Laboratory Department of Homeland Security NY 10014-4811 USA

A better understanding of the variation of 210Pb concentrations in the surface air is the key to trace lake sedimentation and catchment erosion, to establish and vali-date the global diffusion model of contaminants, and to as-sess the impact of natural radiation on the ecological system. Basing on the study progresses of the sedimentation, the at-mospheric model and the unique environmental background in the Yunnan-Guizhou Plateau, and starting from December 20, 2001, we made use of a 500 NE Type aerosol sampler to collect filter samples, once a week in the past consecutive two years, in the surface air at Mt. Guanfeng, Guiyang City, China. Synchronous detailed γ -energy spectrometric obser-vations of 210Pb concentrations at both Chinese and U.S. laboratories have shown that the average monthly 210Pb concentration displays a regular U-patterns distribution of annual variations, with high values appearing in winter and low values in late spring and summer. The average annual 210Pb concentrations are estimated to be 2.77±0.63 mBq/m3, about 4 times the average maximum concentrations reported from quite a number of monitoring stations throughout the world. The possible factors affecting the sources of 210Pb in the surface air in the central part of Guizhou Province are: Release of 222Rn from the U-Ra series enriched in the soils; chemical weathering of carbonate rocks; the exploitation, processing and utilization of coal and phosphorous resources. The principal factor controlling the high 210Pb concentrations in the surface air in the central Guizhou and their annual U-pattern distribution is the release of 222Rn. The average monthly 210Pb concentrations show a good negative power- function relationship with increasing precipitation and also show a good negative linear-function relationship with the rise of air temperature in month grouping. Group No.1 (June to November) reflects a relatively low release of 222Rn from soils in relatively high temperature seasons; Group

关键词：表面空气铅浓度 U模式分布中国贵州

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δ13C-δ18O Covariance:An Effective Indicator of Hydrological Closure for Lakes?

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Acta Geologica Sinica(English Edition) 2008年第5期82卷 975-981页

作者： CHEN Jing＇an wanG Fushun wan guojiang TANG Degui David Dian ZHANG HUNAG Ronggui LI Jian XIAO Tangfu State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang550002 Guizhou Department of Geography University of Hong Kong Pokfulam Road Hong Kong

The correlation between the δ^13C and δ^13C-δ^18O in primary carbonates is affected by several factors such as hydrological balance, total CO2 concentrations, climatic condition and lake productivity. The influence of these factors on the δ^13C-δ^18O correlation may be different on different time scales. In this paper, two different-type lakes in southwestern China, Lake Erhai and Lake Chenghai, are selected to investigate the influence of climatic pattern on the δ^13C-δ^18O correlation and to evaluate the reliability of the δ^13C-δ^18O covariance as an indicator of hydrological closure. The results show that there exists good correlation between the δ^13C and δ^18O in Lake Erhai （overflowing open lake） and in Lake Chenghai （closed lake）. This suggests that the δ^13C-δ^18O covariance may be not an effective indicator of hydrological closure for lakes, especially on short time scales. On the one hand, a hydrologically open lake may display covariant δ^13C and δ^18O as a result of climatic influence. The particular alternate warm-dry and cold-wet climatic pattern in southwestern China may be the principal cause of the δ^13C-δ^18O covariance in Lake Erhai and Lake Chenghai. On the other hand, a hydrologically closed lake unnecessarily displays covariant trends between δ^13C and δ^18O because of the buffering effect of high CO2 concentration on the δ^13C shift in hyper-alkaline lakes. We should be prudent when we use the covariance between δ^13C and δ^18O to judge the hydrological closure of lake.

关键词： carbonates δ^13C-δ^18O covariance hydrological closure climatic pattern

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