长春秋季生物质燃烧对PM2.5中WSOC吸光性的影响  

Effect of Biomass Burning on the Light Absorption Properties of Water Soluble Organic Carbon in Atmospheric Particulate Matter in Changchun

作　　者：孟德友 曹芳 翟晓瑶 张世春[3] 章炎麟 MENG De-you;CAO Fang;ZHAI Xiao-yao;ZHANG Shi-chun;ZHANG Yan-lin(School of Applied Meteorology,Nanjing University of Information Science&Technology,Nanjing 210044,China;International Joint Laboratory on Climate and Environment Change(ILCEC),Yale-NUIST Center on Atmospheric Environment,Nanjing 210044,China;Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun 130102,China)

机构地区：[1]南京信息工程大学应用气象学院,南京210044 [2]耶鲁大学-南京信息工程大学大气环境中心,气候与环境变化国际合作联合实验室,南京210044 [3]中国科学院东北地理与农业生态研究所,长春130102

出　　处：《环境科学》2020年第6期2547-2554,共8页Environmental Science

基　　金：国家重点研发计划项目(2017YFC0212302);国家自然科学基金项目(41977185,41977305);江苏省自然科学杰出青年基金项目(BK20180040);江苏省双创团队基金项目。

摘　　要：为探究长春秋季生物质燃烧对PM2.5中水溶性有机碳(water-soluble organic carbon,WSOC)吸光性的影响,于2017年10~11月进行PM2.5样品采集,对PM2.5中碳质组分、糖类化合物和WSOC的光吸收特征参数进行分析.研究表明:长春秋季PM2.5中WSOC、有机碳(organic carbon,OC)、元素碳(elemental carbon,EC)的平均浓度分别为(10.12±3.47)、(17.07±5.64)和(1.34±0.75)μg·m^-3,二次有机碳(secondary organic carbon,SOC)对OC的平均贡献率为38.93%.长春秋季总糖浓度为(1049.39±958.85)ng·m^-3,其中作为生物质燃烧示踪剂的脱水糖含量(左旋葡聚糖、半乳聚糖和甘露聚糖)在总糖中占比为91.69%,糖类相关性分析结果显示生物质燃烧源为长春秋季大气中糖类物质的主要贡献源.糖类物质的相关性分析及3种脱水糖的特征比值研究显示,作为长春秋季大气主要污染源的生物质燃烧的类型是硬木和作物残渣的燃烧.长春秋季WSOC的光吸收波长指数(AAE)为5.75±1.06,单位质量吸收效率(MAE)为(1.23±0.28)m^2·g^-1,表明生物质燃烧对WSOC吸光性具有重要影响.利用生物质燃烧特征源参数量化计算生物质燃烧对WSOC浓度的贡献达58.82%,对总WSOC光吸收的贡献达40.92%.To investigate the effect of biomass burning in Changchun in autumn on the absorbance of water-soluble organic carbon(WSOC)on PM2.5,PM2.5 samples were collected from October to November 2017.The light absorption characteristics of WSOC,carbonaceous components,and carbohydrate content in PM2.5 were analyzed.The study showed that the average concentrations of WSOC,organic carbon(OC),and elemental carbon(EC)in PM2.5 in Changchun were(10.12±3.47),(17.07±5.64),and(1.34±0.75)μg·m^-3,respectively;the average contribution rate of secondary organic carbon(SOC)to OC was 38.93%.The total sugar concentration in Changchun is(1049.39±958.85)ng·m^-3,of which the content of anhydroglucose(L-glucan,galactan,and mannan),as a biomass burning tracer in total sugar,was 91.69%.The results of sugar correlation analysis showed that biomass combustion was the main source of contribution to carbohydrates in the autumn of Changchun.The light absorption wavelength index of WSOC in autumn was 5.75±1.06,and the unit mass absorption efficiency was(1.23±0.28)m^2·g^-1,indicating that biomass combustion has an important influence on WSOC absorbance.The biomass combustion characteristic source parameter was used to quantify the contribution of biomass burning to WSOC concentration,which was found to be 58.82%,while the contribution to total WSOC light absorption was 40.92%.

关 键 词：水溶性有机碳(WSOC) 糖 左旋葡聚糖 生物质燃烧 吸光性 

分 类 号：X513[环境科学与工程—环境工程]