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Characterization of MASDs of surface soils in north china and its influence on estimating dust emission

chinese Science Bulletin 2004年第20期49卷 2169-2176页

作者： mei fanmin1,2. ZHANG Xiaoye1. LU Huayu1.{1.,{2., chinese academy of sciences, xian 710075, china 2. xian University of Engineering Science and Technology, xian 71.048, china state {1. {2. of {2. and quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China Xi''an University of Engineering Science and Technology Xi''an 710048 China

The micro-aggregated size distribution (MASD) of surface soil is an important parameter for modelling dust emission. However, there is no dataset of MASDs of all sur-face soil types in north china. The MASDs are here pre-sented, measured by dry sieving, for typical surface soil sam-ples, including sandy soil, gravelly sand soil, gravelly loam soil, loam soil and silt loam soil, collected from sandy deserts, Gobi deserts, oases, farmlands in steppe regions and steppe areas in north china. The MASDs of various surface soil types exhibit a combination of several log-normal distribu-tions of five separated sizes with mean mass median diame-ters (MMDs) of 90, 2.2., 390, 600 and 980 mm, respectively, and mean standard deviations (SDs) of {2.2., {2.40, {2.2., {2.35 and {2.2. respectively. The log-normal distributions corre-spond to very fine sand, fine sand, medium sand, coarse sand and very coarse sand population. On the basis of characteri-zation of the retrieved MASDs of various surface soil types in north china, dust emission fluxes are modelled by a dust production model (DPM model). It is shown that dust emis-sion has been significantly influenced by MASDs. Fine sand and very fine sand are always associated with the highest dust emission fluxes. Emission fluxes of the medium sand, gravelly sand soil, gravelly loam soil and loam soil are lower than those of very fine sand and fine sand, but larger than those of the coarse sand. The differences in dust emission fluxes vary among the different soil types from {2.{2.to {2.3 mg·m-2.s-{2. Dust emission fluxes from sandy deserts and farmlands covered with sand sheets in north china rang from {2.{2.to {2.4 mg·m-2.s-{2.while those from Gobi deserts, farmlands and steppes with gravelly desertification range from {2.{2.to {2.2.mg·m-2. s-{2. The modelled results indicate that deserts and farmlands with sand are the major dust sources in north china.

关键词：华北地区 MASDs 微块状粒度分布地面土壤粉尘排放壤土大气污染气溶胶

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Concentration Characteristics and Sources of Chemical Elements in Atmospheric Fine Particles (PM_(2.5)) in Autumn in Xi'an City

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Meteorological and environmental Research 2011年第4期2卷 5-8页

作者： GAN Xiao-feng1,2. CAO Jun-ji2.3, wang Qi-yuan4, {1. Zhen-xing4, XU Hong-{2.2.1. Department of {2.al Science and Technology, Xi’an Jiaotong University, Xi’an 710049, china 2. state key laboratory of loess and quaternary geology, institute of earth environment,{1.}, Xi’an {1.}, china 3. {1.} of Global {2.al Change, Xi’an Jiaotong University, Xi’an 710049, china 4. Department of {2.al Engineering, Xi’an Jiaotong University, Xi’an 710049, china

[Objective] The aim was to study the concentration characteristics and sources of chemical elements in atmospheric fine particles (PM2.5) in autumn in Xi’an City. [Method] By means of mini-volume sampler, PM2.5 samples in atmosphere in Xi’an were collected in October 2.09, and the concentration characteristics and sources of elements in PM2.5 were analyzed. [Result] The average mass concentration of PM2.5 in atmosphere in autumn in Xi’an City was 1.8.44 μg/m3 which was higher than that of Beijing and Pearl River Delta area, and the minimum and maximum value were 53.2. and 358.1. μg/m3, respectively. The mass concentration of S, Zn, K, Cl, Ca and Fe in PM2.5 was above 1.0 μg/m3, being at high pollution level. In addition, K had obvious correlation with organic carbon (OC) and element carbon (EC), with the correlation coefficients of 0.76 and 0.75 (P1., respectively, and it showed that OC and EC had the same source as K, namely biomass burning had certain contribution to OC and EC. Enrichment factors analysis revealed that K, Ca, Fe, Ti, Mn and Cr mainly came from earth crust, rock weathering and other natural sources, while anthropogenic pollution sources had great effects on S, Zn, Cl, Pb, Br, Mo, Cd and As which were affected by soil dust and other natural sources slightly, and Cd had the highest enrichment factor and mainly came from metal smelting. In a word, coal combustion, biomass burning, vehicle emissions, metallurgical, chemical industry and dust were the main sources of PM2.5 in autumn in Xi’an. [Conclusion] The study could provide theoretical foundation for the control of urban {1.al pollution.

关键词： Atmospheric fine particles Chemical element Enrichment factor Factor analysis china

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Real-time measurements of PM_(2.5),PM_(1.-2.5),and BC in an urban street canyon

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Particuology 2015年第3期13卷 134-140页

作者： Yan Cheng Shun Cheng Lee Yuan Gao Long Cui Wenjing Deng Junji Cao zhenxing {1. Jian Sun Department of environmental Science and Technology School of Human Settlements and Civil EngineeringXi'an Jiaotong University SKLLQG Institute of Earth and EnvironmentCAS Department of Civil and environmental Engineering Research Center for Environmental Technology and ManagementThe Hong Kong Polytechnic University Department of Science and environmental Studies and Centre for Education for environmental Sustainability The Hong Kong Institute of Education

A continuous dichotomous beta gauge monitor was used to characterize the hourly content of PM2.5, PM1.-2.5, and Black Carbon （BC） over a 1.-month period in an urban street canyon of Hong Kong. Hourly vehicle counts for nine vehicle classes and meteorological data were also recorded. The average weekly cycles of PM2.5, PM1.-2.5, and BC suggested that all species are related to traffic, with high concentrations on workdays and low concentrations over the weekends. PM2.s exhibited two comparable concentrations at 1.：00-1.：00 （63.4 μg/m3） and 1.：00-1.：00 （65.0 p.g/m3 ） local time （LT） during workdays, correspond- ing to the hours when the numbers of diesel-fueled and gasoline-fueled vehicles were at their maximum levels： 31.9 and 2.07 h-1. respectively. BC is emitted mainly by diesel-fueled vehicles and this showed the highest concentration （31.2.g/m3） during the midday period （1.：00-1.：00 LT） on workdays. A poor correlation was found between PM2.s concentration and wind speed （R= 0.51. P-value 〉 0.001.）. In contrast, the concentration of PM1.-2.s was found to depend upon wind speed and it increased with obvious statistical significance as wind speed increased （R = 0,98, P-value 〈 0.0001.）.

关键词： PM2.5 PMl0 2.5BCHong KongUrban street canyon

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汉中市秋季PM_(2.5)昼夜变化特征

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地球环境学报 2019年第1期10卷 79-86页

作者：张勇刘随心曹军骥田杰张婷朱崇抒孙健沈振兴中国科学院地球环境研究所黄土与第四纪地质国家重点实验室中国科学院气溶胶化学与物理重点实验室西安710061 中国科学院大学北京100049 西安交通大学环境科学与工程系西安710049

为探讨汉中市秋季PM_(2.5)昼夜变化特征。于2.1.年9月7日至9月1.日利用中流量大气颗粒物采样仪在汉中市三个不同站点分昼夜采集PM_(2.5)滤膜样品,并分别利用热光碳分析仪(DRI—2.1.)和离子色谱(Dionex—600)分析PM_(2.5)中碳组分和水溶... 详细信息

为探讨汉中市秋季PM_(2.5)昼夜变化特征。于2.1.年9月7日至9月1.日利用中流量大气颗粒物采样仪在汉中市三个不同站点分昼夜采集PM_(2.5)滤膜样品,并分别利用热光碳分析仪(DRI—2.1.)和离子色谱(Dionex—600)分析PM_(2.5)中碳组分和水溶性离子组分,主要探讨PM_(2.5)及其碳组分和水溶性离子昼夜变化特征。结果显示:汉中秋季PM_(2.5)浓度低于国家空气质量一级标准;PM_(2.5)中主要化学组分包括SNA (硫酸盐、硝酸盐、铵盐)和有机类物质,白天和夜间占比分别达到32.3%、39.6%和2..9%、39.6%; PM_(2.5)颗粒物呈酸性。除SO_4^(2.)、Mg^(2.)和Ca^(2.)之外,PM_(2.5)及其化学组分均呈现夜间浓度高于白天的特征。离子的赋存形态分析表明:SO_4^(2.)更多以(NH_4^+)_2.O_4^(2.)的形式存在于PM_(2.5)中。本文相关结果可为地方环保政策的制定提供参考和基础数据。

关键词：汉中 PM2.5 碳组分水溶性离子

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