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

作     者：XU Gang LEE XinQing LU YingChun CHEN YingJun HUANG DaiKuan 

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) 

主　　题：雨水 酸雨 离子色层谱 羧基的酸 季节的变化 

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.