To understand the changes in the components of volatile organic compounds(VOCs), the contribution proportion of each component to ozone, and the VOCs sources, we monitored the VOCs for a year in Lishui. The results showed that theρ(TVOC) was 223.46 μg·m-3, ρ(alkanes) was 49.45 μg·m-3(22.3%), ρ(OVOCs) was 50.63 μg·m-3(22.66%), ρ(halogenated hydrocarbons) was 64.73 μg·m-3(28.95%), ρ(aromatic hydrocarbons) was 35.46 μg·m-3(15.87%), ρ(alkenes) was 18.26 μg·m-3(8.19%), and ρ(others) was 4.9 μg·m-3(2.2%). ρ(TVOC) was higher in summer(263.75 μg·m-3) and lower in winter(187.2 μg·m-3), with 246.11 μg·m-3 in spring and 204.77 μg·m-3 in autumn. The daily concentration of VOCs showed two peaks, one from 9:00 to 10:00 and another from 14:00 to 15:00, and the high concentration was mainly found in the urban main road area with dense human activities. The ozone formation potential(OFP) was 278.92 μg·m-3, and those of olefin and aromatic hydrocarbon were 114.47 μg·m-3(41.1%) and 113.49 μg·m-3(40.8%), respectively, contributing over 80%, which was an important precursor of ozone. On the other hand, the ratio of characteristic compounds to toluene/benzene(T/B) was 4.13, which indicated that it was greatly affected by the solvent usage. In the end, the results of positive matrix factorization(PMF) source apportionment showed that VOCs mainly came from solvent usage, industrial production, and traffic emissions. The VOCs pollution had a great influence on ozone, so it was necessary to strengthen the treatment of industrial production, solvent usages, and traffic emissions.
Keywords: Lishui of Nanjing; mobile monitoring; ozone formation potential(OFP); source apportionment; volatile organic compounds(VOCs).