Abstract:Air samples were collected from one farm in Jiaxing, Zhejiang Province and analyzed for carbonyl compounds. The carbonyl compounds concentrations were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and 32 carbonyls species were quantified. Formaldehyde, acetaldehyde, nonanaldehyde/2-nonanone and dodecanal were the most abundant species with mean concentrations of 13.99, 8.76, 7.77 and 7.13μg/m3, and accounted for 18.29%, 11.45%, 10.16% and 9.32% of the total carbonyls, respectively. Photochemical reaction and plant emission, in particular for rice emission, were main sources of atmospheric carbonyl compounds in the farm of Jiaxing. Rice harvest activity was another source of acetaldehyde and hexaldehyde. There was a significant linear correlation between formalddehyde and acetaldehyde (r=0.58, P0.70, P<0.01), and the correlation coefficients of nonanaldehyde/2-nonanone, octylaldehyde, decaldehyde, undecanal, dodecanal and tridecanal were in the range of 0.95~0.99(P<0.01), which indicated that these high-molecular-weight carbonyls (C37) had same sources. Rice emission was considered to be their main common source.