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Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science china Earth sciences 2008年第12期51卷 1776-1785页

作者： xiAO YingKai1,2, LI HuaLing1,3, liu weiguo4, wang xiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, chinese academy of sciences, xining 810008, china 2 state key laboratory of environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3 Nanjing institute of geology and Mineral Resources, Nanjing 210016, china 4 state key laboratory of loess and quaternary geology, institute of Earth environment, chinese academy of sciences, xi’an 710075, china 5 state key laboratory for Mineral Deposits Research, Department of Earth sciences, Nanjing University, Nanjing 210093, china Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China state key {2. of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China Nanjing institute of geology and Mineral Resources Nanjing China state key {2. of loess and quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China state key {2. for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34 was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4-pH curves and neither do they exactly parallel any theoretical δ 11B4-pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4- in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4-3) between B(OH)4- and B(OH)3 is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water

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Science china Chemistry 2006年第5期49卷 454-465页

作者： xiAO Yingkai1,2.LI Shizhen1,WEI Haizhen1,SUN Aide1,ZHOU Weijian2.& liu {2.2.1. Qinghai institute of Salt Lakes,chinese academy of sciences,xining 810008,china 2. state key laboratory of loess and {12. geology,institute of Earth environment,chinese academy of sciences,xi’an 710075,china Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China state key {2. of loess and quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China

Inorganic calcium carbonate precipitation from natural seawater and salinewater at various pH values was carried out experimentally. The results show the clear positiverelationships between boron concentration and δ^(11)B of inorganic calcium carbonate with the pH ofnatural seawater and saline water. However, the variations of boron isotopic fractionation betweeninorganic calcite and seawater/saline water with pH are inconsistent with the hypothesis thatB(OH)_4^- is the dominant species incorporated into the biogenic calcite structure. The isotopicfractionation factors a between synthetic calcium carbonate precipitate and parent solutionsincrease systematically as pH increases, from 0.9884 at pH 7.60 to 1.0072.at pH 8.60 for seawaterand from 0.982. at pH 7.60 to 1.0178 at pH 8.75 for saline water. An unusual boron isotopicfractionation factor of larger than 1 in synthetic calcium carbonate precipitated fromseawater/saline water at higher pH is observed, which implies that a substantial amount of theisotopically heavier B(OH)_3 species must be incorporated preferentially into synthetic inorganiccarbonate. The results propose that the incorporation of B(OH)_3 is attributed to the formation ofMg(OH)_2.at higher pH of calcifying microenvironment during the synthetic calcium carbonateprecipitation. The preliminary experiment of Mg(OH)_2.precipitated from artificial seawater showsthat heavier ^(11)B is enriched in Mg(OH)_2.precipitation, which suggests that isotopically heavierB(OH)_3 species incorporated preferentially into Mg(OH)_2.precipitation. This result cannot beapplied to explain the boron isotopic fractionation of marine bio-carbonate because of thepossibility that the unusual environment in this study appears in formation of marine bio-carbonateis infinitesimal. We, however, must pay more attention to this phenomenon observed in this study,which accidentally appears in especially natural environment.

关键词： boron, isotopic fractionation, calcium carbonate precipitate, seawater, saline water.

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. liu Yu2.& TAN Ming31. South{2. Sea institute of Oceanology, chinese academy of sciences. Guangzhou 510301,{2. 2. state key laboratory of loess and quaternary geology, Earth {12.al institute, chinese academy of sciences, xi’an 710075,{2. 3. institute of geology and Geophysics, chinese academy of sciences, Beijing 10002.,{2. South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China state key {2. of loess and quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3,liu xiaoDong 4 & TIAN ZhiPing 2,5 1 Climate Change Research Center,chinese academy of sciences,Beijing 100029,china 2 Nansen-Zhu International Research Centre,institute of Atmospheric Physics,chinese academy of sciences,Beijing 100029,china 3 key laboratory of Regional Climate-environment Research for Temperate East Asia,chinese academy of sciences,Beijing 100029,china 4 state key laboratory of loess and quaternary geology,institute of Earth environment,chinese academy of sciences,xi’an 710075,china 5 Graduate University of chinese academy of sciences,Beijing 100049,china Climate Change Research Center Chinese Academy of Sciences Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences key laboratory of Regional Climate-{2. Research for Temperate East Asia Chinese

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National Center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

Sun-coupled climate connection between eastern Asia and northern Atlantic

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Sun-coupled climate connection between eastern Asia and nort...

Nitrous Oxide and Methane Emissions as Affected by Water,Soil and Nitrogen

中国科学院地质与地球物理研究所2.04学术年会

作者： Ming Tan institute of geology and Geophysics,chinese academy of sciences,Beijing,china state key laboratory of loess and quaternary geology,institute of Earth environment,chinese academy of sciences, xi’an.Shaanxi,china Juzhi Hou institute of geology and Geophysics,chinese academy of sciences,Beijing,china Tungsheng liu institute of geology and Geophysics,chinese academy of sciences.Beijing,china state key laboratory of loess and quaternary geology.institute of Earth environment.chinese academy of sciences. xi’an.Shaanxi.china

[1]Few of annually resolved Proxy temperature records are reported to coincide with centennial

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Pedosphere 2007年第2期17卷 146-155页

作者： xiONG zheng-Qin xiNG Guang-xi ZHU Zhao-Liang state key {2. of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. Department of Physics Portland State University Portland Oregon 97207 （USA）

Specific management of water regimes, soil and N in china might play an important role in regulating N2. and CH4 emissions in rice fields. Nitrous oxide and methane emissions from alternate non-flooded/flooded paddies were monitored simultaneously during a 516-day incubation with lysimeter experiments. Two N sources (15N-(NH4)2.O4 and 15N-labeled milk vetch) were applied to two contrasting paddies: one derived from xiashu loess (loess) and one from quaternary red clay (Clay). Both N2. and CH4 emissions were significantly higher in soil Clay than in soil loess during the flooded period. For both soil, N2. emissions peaked at the transition periods shortly after the beginning of the flooded and non-flooded seasons. Soil type affected N2. emission patterns. In soil Clay, the emission peak during the transition period from non-flooded to flooded conditions was much higher than the peak during the transition period from flooded to non-flooded conditions. In soil loess, the emission peak during the transition period from flooded to non-flooded conditions was obviously higher than the peak during the transition period from non-flooded to flooded conditions except for milk vetch treatment. Soil type also had a significant effect on CH4 emissions during the flooded season, over which the weighted average flux was 111 mg C m-2.h-1 and 2.2.mg C m-2.h-1 from Clay and loess, respectively. Results indicated that it was the transition in the water regime that dominated N2. emissions while it was the soil type that dominated CH4 emissions during the flooded season. Anaerobic oxidation of methane possibly existed in soil loess during the flooded season.

关键词： anaerobic oxidation of methane (AOM) dissimilatory nitrate reduction to ammonium (DNRA) greenhouse gasses lysimeter paddy soil

Characteristics of indoor and outdoor black carbon aerosol during winter and summer in rural area of Guanzhong Plain

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Characteristics of indoor and outdoor black carbon aerosol d...

Interpreting Larix principis-rupprechtii radial growth in northern china based on the Vaganov-Shashkin model

第十届全国气溶胶会议暨第六届海峡两岸气溶胶技术研讨会

作者： Zhu Chongshu1,2.Cao Junji1,Shen Zhen xing3,liu Sui xin1,2.1.state {2. Lab of loess & quaternary geology,institute of Earth environment,chinese academy of sciences,xi’an,Shanxi 710075,{12. 2.Graduate School of the chinese academy of sciences,Beijing 100039,{12. 3.Department of environmental Science and Engineering,xi’an Jiaotong University,xi’an,{12..)

Black Carbon（BC） were measured continuously in rural area of Guanzhong Plain during winter and *** concentrations of BC varied acutely over a range of 3.9-2..6 μg m-3 for outdoor and 4.8-2..7 μg m-3 for indoor in daily mean concentration,with the overall average values of 14.6 μg m-3 and 14.4 μg m-3 for outdoor and indoor in winter,*** mean BC concentrations varied over a range of 2.9-9.9μg m-3 for outdoor and 4.7-10.2.g m-3 for indoor,with the overall average value of 6.0 μg m-3 and 7.2.μg m-3 for outdoor and indoor,respectively in *** results shows the concentrations of black carbon is high in the rural area,especially in winter,which is probably due to the local biomass burning for warming and *** rural area of Guanzhong Plain,Obviously diurnal variation of BC was observed,with the hourly average concentrations ascending to its peaks twice a day in the morning and at the *** frequency distributions of BC concentrations in both indoor and outdoor environments showed a similar *** indoor environment,it was found that the BC concentrations were distributed over the high spectrum of concentrations than that for outdoor *** relationships between indoor and outdoor concentrations（separately for LT,WN and HX sites） of BC were discussed,which showed a good correlation between indoor and outdoor air of the three *** results suggest that indoor black carbon was derived at least in part from outdoor air.

关键词： Black carbon rural area Guanzhong Plain

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Journal of Forestry Research 2024年第3期35卷 99-110页

作者： Jiachuan wang Shuheng Li Qiang Li Yili Guo Yijie Han Qi liu Yiqi Zhao College of Urban and environmental sciences Northwest UniversityXi'an 710127People's Republic of China institute of Global environmental Change Xi'an Jiaotong UniversityXi'an 710049People's Republic of China Shaanxi key laboratory of Earth Surface System and {2.al Carrying Capacity Northwest UniversityXi'an 710127People's Republic of China state key {2. of loess and quaternary geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061People's Republic of China

Changes in annual radial growth is an important indication of climate change. Dendroclimatology studies in northern china have focused on linear statistical analysis,but lacking studies based on the process of ring formation to clarify the radial growth of trees. Tree-ring width standard chronology(STD) was established using samples of Larix principis-rupprechtii collected at 2.03 m altitude on Luya Mountain. Using the Vaganov-Shashkin(VS) model to simulate growth and development, the internal physiological mechanism of radial growth is identified. It was concluded that:(1) the growing season of L. principis-rupprechtii was May to September;(2. soil moisture was a significant factor in the early and late growing seasons, and temperature was the dominant factor in its main growth period;and(3) formation of narrow ring widths was closely related to drought stress, the development of wide ring widths will be restricted by increasing future temperatures. The VS model is applicable for radial growth simulation of subalpine coniferous forests and for guiding the cultivation of local tree species in the future.

关键词： Vaganov-Shashkin model Larix principis-rupprechti Tree-ring width Annual growth

Carbon isotope and environmental changes in lakes in arid Northwest china

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Science china Earth sciences 2019年第8期62卷 1193-1206页

作者： weiguo liu xiangzhong LI {2. wang Huangye wang Hu liu Bo ZHANG Huan ZHANG institute of Earth environment CASState Key Laboratory of Loess and Quaternary GeologyXi’an 710061China University of chinese academy of sciences Beijing 100049China

The stable carbon isotope composition(δ13 C) of lacustrine sediments, which can record changes in past environmental conditions such as the C4/C3 terrestrial vegetation composition, has been widely used for the reconstruction of terrestrial ecosystems and global climate changes. It has also been widely used in paleolimnological studies in arid northwestern china. In recent years, however, an increasing number of studies have enriched the environmental significance reflected by the stable carbon isotope geochemistry of lakes;therefore, the interpretation of lake δ13 C variations in paleoenvironmental reconstructions should be carefully evaluated from various aspects. In this paper, previous studies from the past several decades on the lacustrineδ13 C variations in arid northwestern china were reviewed, and the possible mechanisms of the δ13 C variations were *** study will provide a reference for the application of carbon isotope geochemistry in paleoenvironmental reconstructions.

关键词： Carbon isotope Lake Arid region of northwestern china Total organic carbon Organic biomarkers