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Seasonal variation and sources of low molecular weight organic acids in precipitation in the rural area of Anshun

Chinese Science Bulletin 2011年第10期56卷 1005-1010页

作者： ZHANG YanLin lee xinqing CAO Fang HUANG DaiKuan State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Low molecular weight (LMW) organic acids are important and ubiquitous chemical constituents in the atmosphere.A comprehensive study of the chemical composition of precipitation was carried out from June 2007 to June 2008 at a rural site in Anshun,in the west of Guizhou Province,*** this period,118 rainwater samples were collected and the main LMW carboxylic acids were determined using ion *** average pH of rainwater was 4.89 which is a typical acidic *** most abundant carboxylic acids were formic acid (volume weight mean concentration:8.77 μmol L-1) and acetic acid (6.90 μmol L-1),followed by oxalic acid (2.05 μmol L-1).The seasonal variation of concentrations and wet deposition fluxes of organic acids indicated that direct vegetation emissions were the main sources of the organic *** concentrations were observed in winter and were ascribed to the low winter rainfall and the contribution of other air pollution sources northeast of the study *** ratio of formic and acetic acids in the precipitation ([F/A] T) was proposed as an indicator of pollution *** suggested that the pollution resulted from direct emissions from natural or anthropogenic *** with acid precipitation in other urban and rural areas in Guizhou showed that there was a decreasing contribution of LMW organic acids to free acidity and all anions in rainwater from urban to remote rural ***,it is necessary to control emissions of organic acids to reduce the frequency of acid rain,especially in rural and remote areas.

关键词：低分子量有机酸农村地区季节变化降水安顺平均浓度化学成分污染来源

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Characteristics and distribution of low molecular weight organic acids in the sediment porewaters in Bosten Lake, China

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Journal of Environmental Sciences 2010年第3期22卷 328-337页

作者： Min Xiao Fengchang Wu Haiqing Liao Wen Li xinqing lee Rongsheng Huang State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550002 China Graduate School of Chinese Academy of Sciences Beijing 100039 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

The composition and vertical profiles of low molecular-weight organic acids （LMWOAs） and the contribution of them to dissolved organic matter （DOM） in sediment porewaters in Bosten Lake, Xinjiang, China were investigated. The results showed that total concentration of LMWOAs was up to 94.5 μmol/L and their proportion in DOM was 5.6%, suggesting that LMWOAs were important chemical components in DOM in lake sediment porewaters. Among the seven LMWOAs, pyruvic and acetic acid had the highest concentrations with 26.30 and 8.31 μmol/L, accounting for 51.4% and 14.92% of LMWOAs, respectively. Trifluoroacetic and sorbic acid had the lowest concentrations, indicating that the compositions of LMWOAs in relative reducing environments were largely different from those reported in glacier, atmosphere and soils. The concentrations of lactic, acetic, formic, sorbic and oxalic acid decreased with increasing depth, probably relating to stronger microbial activities in the initial stage of early diagenesis. Trifluoroacetic acid was mainly anthropogenic with its concentration, showing a diusive trend from the surface to bottom sediments. The concentrations of lactic acid and nitrate generally showed a consistent profile. The increasing concentration of pyruvic acid in the vertical profile was just opposite to that of sulfate, revealing a significant negative relationship between them. Oxalic acid remained constant except for an obvious peak at 6 cm depth. The results indicated the diversities in sources and behaviors for various LMWOAs during early diagenesis in sediments.

关键词： dissolved organic matter low molecular-weight organic acids sediment porewaters early diagenesis

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Diurnal and spatial variations of soil NO_x fluxes in the northern steppe of China

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Journal of Environmental Sciences 2015年第6期27卷 54-61页

作者： Bing Wang xinqing lee Benny K.G. Theng Jianzhong Cheng Fang Yang State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Landcare Research Private Bag 11052 Graduate University of the Chinese Academy of Sciences

NOx emissions from biogenic sources in soils play a significant role in the gaseous loss of soil nitrogen and consequent changes in tropospheric chemistry. In order to investigate the characteristics of NOx fluxes and factors influencing these fluxes in degraded sandy grasslands in northern China, diurnal and spatial variations of NOx fluxes were measured in situ. A dynamic flux chamber method was used at eight sites with various vegetation coverages and soil types in the northern steppe of China in the summer season of *** of NOx from soils with plant covers were generally higher than those in the corresponding bare vegetation-free soils, indicating that the canopy plays an important role in the exchange of NOx between soil and air. The fluxes of NOx increased in the daytime,and decreased during the nighttime, with peak emissions occurring between 12：00 and14：00. The results of multiple linear regression analysis indicated that the diurnal variation of NOx fluxes was positively correlated with soil temperature（P 〈 0.05） and negatively with soil moisture content（P 〈 0.05）. Based on measurement over a season, the overall variation in NOx flux was lower than that of soil nitrogen contents, suggesting that the gaseous loss of N from the grasslands of northern China was not a significant contributor to the high C/N in the northern steppe of China. The concentration of NOx emitted from soils in the region did not exceed the 1-hr National Ambient Air Quality Standard（0.25 mg/m^3）.

关键词： Desertification N cycle Land-use change Nitrogen oxides

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Metabolic effects on stable carbon isotopic composition of freshwater bivalve shell Corbicula fluminea

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Chinese Journal Of Geochemistry 2012年第1期31卷 103-108页

作者： YAN Hui LI Zhongxuan lee xinqing ZHOU Hui CHEN Jie College of Urban Planning and Environment Science Xuchang UniversityXuchang 461000China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China

The stable isotopic composition of the bivalve shell has been widely used to reconstruct the pa-laeo-climate and palaeo-environment. The climatic and environmental significance of carbon isotopic composition of the bivalve shell is still in dispute, and incorporation of metabolic carbon can obscure carbon isotope records of dis-solved inorganic carbon. This study deals with freshwater bivalve, Corbicula fluminea aragonite shell. The results indicated that the δ13C values of bivalve shells deposited out of equilibrium with the host water and showed an onto-genic decrease, indicating that there are metabolic effects and more metabolic carbon is incorporated into larger shells. The proportion of metabolic carbon of shells varies between 19.8% and 26.8%. However, δ13CS can still be used as qualitative indicators of δ13CDIC and environmental processes that occurred during shell growth.

关键词：稳定碳同位素组成淡水贝类代谢双壳河蚬碳同位素记录溶解无机碳生长过程

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Seasonal variations of carboxylic acids and their contributions to the rainwater acidity: A case study of Guiyang and Shangzhong,China

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Chinese Science Bulletin 2010年第16期55卷 1667-1673页

作者： XU Gang lee xinqing LU YingChun CHEN YingJun HUANG DaiKuan Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Low molecule weight carboxylic acids are ubiquitous and important chemical constituents in the *** carboxylic acids in the rainwater of Guiyang and Shangzhong were simultaneously determined by ion chromatography from April 2006 to April ***, acetic and oxalic acids were found to be the predominant carboxylic *** volume weighted average concentration (VWA) in the rainwater of Guiyang were 14.24 μmol/L, 9.35 μmol/L and 2.79 μmol/L, respectively;as compared to 4.95 μmol/L, 1.35 μmol/L and 2.31 μmol/L in the rainwater of *** Shangzhong it is witnessed that the concentra-tions of these acids were higher in the summer than in the winter and direct emissions from vegetations or soils may account for the main provenance of the *** is, however, not the case in Guiyang, where the concentrations of the carboxylic acids were higher during the non-growing season than during the growing *** relatively weak scavenging affected by scarce and little rainwater as well as the particles accompanied with the rainfall may have some effect on the carboxylic acids during the wintertime in *** acids in the rainwater of Guiyang were estimated to account for 18.7% to the free acidity, where formic, acetic and oxalic acids accounted for 7.9%, 4.7%, 6.1%, *** Shangzhong, the 3 primary carboxylic acids represented 58.1% to the free acidity where formic, acetic and oxalic acids represented 25.1%, 7.5%, 25.5%, *** anions accounted for 6.6% (1.7%–19.2%) to the total anions in the rainwater of *** anions repre-sented 13.2% (0.5%–92.2%) to the total anions in the rainwater of *** results indicated that carboxylic acids were the important contributors to the rainwater acidity, especially in remote regions.

关键词：雨水酸雨离子色层谱羧基的酸季节的变化

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Nitrous oxide emissions from different land use patterns in a typical karst region, Southwest China

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Chinese Journal Of Geochemistry 2013年第2期32卷 137-145页

作者： CHENG Jianzhong lee xinqing ZHOU Zhihong WANG Bing XING Ying CHENG Hongguang State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Fluxes of nitrous oxide (N2O) from different land use patterns (matured forest, secondary forest, grassland and cropland) in a subtropical karst region of Guizhou Province, Southwest China, were measured for one year with a closed static chamber technique and by gas chromatography. The results showed that soil under different land uses was a source of atmospheric N2O. The cropland was a source with relatively high N2O as compared to forest and grassland, but no significant differences were observed. N2O emissions from soils varied with land use change and fertilizer application. There were two peaks of N2O flux occurred following the combination of two obvious precipitation and fertilizer events in the cultivated land. Converting from the matured forest to secondary forest tended to increase annual emissions of N2O (from 1.40 to 1.65 kg N ha -1 a -1 ), while changing land use from secondary forest to scattered grassland tended to decrease annual emissions of N2O slightly (from 1.65 to 1.45 kg N ha -1 a -1 ). Our range of cumulative annual N2O emission across different land uses (1.40-1.91 kg N ha -1 a -1 ) in a karst region is in general agreement with previously published data in a non-karst region. However, in the maize field, N2O emission factor (EF) was 0.34% for fertilizer application, which is about 71.2% lower than the IPCC default value. It is suggested that current IPCC (Intergovernmental Panel on Climate Change) EF methodology could overestimate N2O emission from the karstic cropland. Anyway, the N2O emission from cropland in the karst region would contribute significantly to the global N2O budget, so reducing fertilization frequency during the crop growing season could lead to a decrease in N2O emission in the whole year.

关键词：氧化亚氮排放土地利用方式中国西南地区喀斯特地区 N2O通量 N2O排放森林草原岩溶地区

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Enhanced removal of sulfonamide antibiotics from water by phosphogypsum modified biochar composite

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Journal of Environmental Sciences 2023年第8期130卷 174-186页

作者： Zonghong Jiang Miao Chen xinqing lee Qianwei Feng Ning Cheng Xueyang Zhang Shengsen Wang Bing Wang College of Resources and Environmental Engineering Guizhou UniversityGuiyang 50025China Key Laboratory of Karst Georesources and Environment Ministry of EducationGuiyang 550025China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China School of Environmental Engineering Xuzhou University of TechnologyXuzhou 221018China College of Environmental Science and Engineering Yangzhou UniversityYangzhou 225127China

Antibiotic pollution has become a global eco-environmental *** reduce sulfonamide antibiotics in water and improve resource utilization of solid wastes,phosphogypsummodified biochar composite(PMBC)was prepared via facile one-step from distillers grains,wood chips,and *** physicochemical properties of PMBCwere characterized by scanning electron microscope(SEM),Fourier transform infrared spectroscopy(FTIR),Zeta potential,X-ray diffraction(XRD),*** influencing factors,adsorption behaviors,and mechanisms of sulfadiazine(SD)and sulfamethazine(SMT)onto PMBC were studied by batch and fixed bed column adsorption *** results showed that the removal rates of SD and SMT increased with the increase of phosphogypsum proportion,while decreased with the increase of solution *** maximum adsorption capacities of modified distillers grain and wood chips biochars for SD were 2.98 and 4.18 mg/g,and for SMT were 4.40 and 8.91mg/g,respectively,which was 9.0–22.3 times that of pristine *** bed column results demonstrated that PMBC had good adsorption capacities for SD and *** the solution flow rate was 2.0 mL/min and the dosage of PMBC was 5.0 g,the removal rates of SD and SMT by modified wood chips biochar were both higher than 50%in 4 *** main mechanisms of SD and SMT removal by PMBC are hydrogen bonding,π-πdonor-acceptor,electrostatic interaction,and hydrophobic *** study provides an effective method for the removal of antibiotics in water and the resource utilization of phosphogypsum.

关键词： Modified biochar Solid waste Antibiotics Phosphogypsum Fixed-bed adsorption

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Effects of biochar-based fertilizers on nutrient leaching in a tobacco-planting soil

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Acta Geochimica 2019年第1期38卷 1-7页

作者： Yunlong Li Jianzhong Cheng xinqing lee Yi Chen Weichang Gao Wenjie Pan Yuan Tang State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Guizhou Academy of Tobacco Science

Biochar is a soil amendment for increasing soil quality and decreasing nutrient leaching. However, there is little information on the impact of biochar-based fertilizer(BF) on soil nutrient leaching in agricultural soils. We conducted a soil column leaching experiment to study the effects of BF on the leaching of total nitrogen(TN), total phosphorus, and total potassium(TK) in tobacco soils. The distribution characteristics of NH_4^+-N, available P, and available K in soil profiles were analyzed after the application of BF. Biochar was prepared by pyrolysis of fluecured tobacco stems. It was applied at four levels, 0%, 3%,9%, and 15%(w/w), respectively, to the compound fertilizer. Compared with the control, the leaching loss of soil TN decreased by 8.36%, 6.72%, and 6.45%, and the loss of soil TK decreased by 9.18%, 9.31% and 11.82% in the 3%,9%, and 15% BF treatments, respectively. However, BF had no significant effect on the P leaching due to the low movement of P in the soil profile. In addition, the BF addition increased the immobilization of NH_4^+-N, available P, and available K in the soil profile. These results indicate that addition of BF to a tobacco-planting soil reduced nutrient leaching, and suggest that BF could be an effective method of applying biochar to agriculture fields.

关键词： Biochar-based fertilizer Soil column Nutrient elements Leaching loss Immobilization

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Removal performance,mechanisms,and influencing factors of biochar for air pollutants:a critical review

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Biochar 2022年第1期4卷 678-701页

作者： Zhipeng Zhao Bing Wang Benny K.G.Theng xinqing lee Xueyang Zhang Miao Chen Peng Xu College of Resource and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Karst Georesources and Environment Ministry of EducationGuiyang 550025China Manaaki Whenua-Landcare Research Palmerston NorthNew Zealand State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Jiangsu Key Laboratory of Industrial Pollution Control and Resource Reuse School of Environmental EngineeringXuzhou University of TechnologyXuzhou 221018China

The emission of air pollutants from various industries is a major contributor to environmental *** removal of these pollutants before they are discharged into the environment has become an important means of controlling air *** has attracted increasing attention because of its low cost,high porosity,large specific surface area,abundant surface functional groups,and high removal *** physicochemical properties of biochar are greatly affected by feedstock types,preparation,and modification *** this reason,the capacity and propensity of biochar for removing air pollutants are rather *** understand the existing research status and grasp the latest research progress,a systematic review on the removal of different air pollutants by biochar is highly *** on the recent research,this paper systematically analyzes and summarizes the preparation and modification methods of biochar commonly used for the removal of six air pollutants(SO_(2),H_(2)S,CO_(2),Hg0,VOCs,and NH_(3)),as well as the removal performance and ***,the potential influencing factors(preparation parameters,physicochemical characteristics of biochar,and removal conditions)are ***,the regeneration of biochar,suggestions,and future perspectives are proposed.

关键词： Biochar Modification Air pollutants Removal performance Removal mechanisms Influencing factors

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Carbon isotope bulk organic matter:A proxy for precipitation in the arid semiarid central Asia

Carbon isotope bulk organic matter:A proxy for precipitation...

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作者： xinqing lee Mark Chopping Staste Key Laboratory of Environmental Gecohemistry Institute of Geochemistry Chinses Academy of Sciences Guiyang china.Fomrerly at National Laboratory of Western China’s Environmental SystemsMinistry of Education (MOE)Lanzhuo University Lanzhouchina. Department of Earth and Environmental studies Montclair State UniversityUpper MontclairNew JerseyUSA.

[1]Carbon isotope composition (δC)of bulk organic matter in soil and lake sediment sequcnces has been widely used to inter past clufcr clinate *** specific climatic representation of the isotopie signa- ***,lacks for *** excellent Gracients of temperature and preeipitation,as well as the graoients of vegetation zone,centfal East Asia provides an ideal background for developing the relationship be- tween the δC and the climatic provides,Analysis ute relationship between transect that crosses the various climatic and vegetation zones reveals a significant linear coneiation between δC and the mean precipitation from May to september yeta vely poor relationship between δC and *** close correiation be- tween the δC and the precipitation is aiso corroborated by measuremcnt of some C3 shrubs along the transecl Precipitation in the arid cehtral East Asia is a key factor controlling the relative competition or the distribution ot piant species with differem photosynthetlc,pathways,thus the carbon isotope in the bulk crganic mateer Its variation,therefore,can be recuvered by measurement of δC in soils or lake sedimeni sequences with terres-

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