Seasonal variations of carboxylic acids and their contributions to the rainwater acidity: A case study of Guiyang and Shangzhong,China
Seasonal variations of carboxylic acids and their contributions to the rainwater acidity: A case study of Guiyang and Shangzhong,China作者机构: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
出 版 物:《Chinese Science Bulletin》 (Chinese Science Bulletin)
年 卷 期:2010年第55卷第16期
页 面:1667-1673页
核心收录:
学科分类:07[理学] 070601[理学-气象学] 0706[理学-大气科学]
基 金:supported by the National Basic Re-search Program of China (2006CB43205) the National Natural Science Foundation of China (4053048)
摘 要: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.