[Effects of elevated O3 on the volatile organic compounds emit from Ginkgo biloba and Pinus tabulaeformis].

To study the impact of elevated tropospheric O3 concentrations on BVOCs emissions by Pinus tabulaeformis and Ginkgo biloba in urban area, the trees were exposed in open-top chambers. Two ozone treatments were established: ambient air (approximately 30 nmol x mol(-1) ) (CK) and elevated O3 concentrations (80 nmol x mol(-1) ) (O3 ). Elevated O3 concentrations significantly induced isoprene to emit for Pinus tabulaeformis and Ginkgo biloba (p < 0.05), and delta3-carene for Ginkgo biloba (p < 0.05). The emission rates were increased to 1.96, 9.71 and 0.09 microg/(g x h) (-1), respectively. There were no significant differences between ozone fumigation treatments for the other monoterpenes. At the same time, the relative abundances of the monoterpenes and isoprene were to be different between tree species and effect by O3 exposure. In CK chambers, the dominate BVOCs emitted by Ginkgo biloba was isoprene, and a-pinene for Pinus tabulaeformis. In the elevated O3 chambers, the isoprene accounted for 64.73% of Pinus tabulaeformis BVOCs. To sum up, the BVOCs emitting patterns were influenced by elevated O3 significantly.