Monitoring the dynamic emission of biogenic volatile organic compounds from Cryptomeria japonica by enclosure measurement

Abstract

Abstract Research on biogenic volatile organic compounds (BVOCs) emitted from trees is essential in the world since these BVOCs play an important role in the atmospheric process which may further influence on the air quality. However, little is known about BVOCs emitted from trees in the field in Taiwan. Hence, this study intends to establish an enclosure technique coupled with in situ sampling to facilitate the collection of BVOCs emitted from Cryptomeria japonica leaves. Furthermore, the emission model derived from the relationship between emission rate and temperature was applied to estimate the emission of BVOCs in the field. Results from GC–MS showed that the BVOCs emitted from intact leaves contain 14 monoterpenoids and 4 sesquiterpenoid. The emission rate of the major constituent, sabinene, was 0.42 μg h−1 g−1 around noon on September 11, 2013. Sabinene varies with the changing temperature inside the bag. These findings indicated that the enclosure technique can collect the BVOCs emitted from intact leaves and monitor the dynamic changes in emission. Two determinants, basal emission rate (at 30 °C) and β coefficient, of sabinene were further measured, and they were 1.29 μg h−1 g−1 and 0.18 °C−1, respectively. By using these two determinants and data of meteorology and forest resource, the emission of monoterpenes from C. japonica stand was estimated to be 1.13 mg m−2 h−1 in July in Xitou area. Taken together, the results provide valuable information for estimation of BVOCs from tree species in Taiwan for the first time.