[Screenings of 23 plant species in Beijing for volatile organic compound emissions]

The VOCs emissions from plants are mainly isoprene and monoterpenes, which account for 2/3 of the total emissions from biosphere. 23 kinds of typical plants in Beijing area were screened to estimate the emission rates of isoprene and monoterpenes by adopting a bag-enclosure sampling method followed by a GC-FID analysis. It was found that such deciduous trees as Sophora japnica and Salix babyloniaca etc. were mainly emitting isoprene and coniferous trees as Pinus tabulaetormis mainly released monoterpenes. The study also showed that the emission of isoprene were affected by both temperature and Photosynthetic Active Radiation (PAR), while monoterpene emissions were mainly temperature-dependent.