Study on Diurnal Variations of Terpenoid Compounds Emitted by Pistacia lentiscus and Its Emission Rate
LIANG Baosheng1) Rita Baraldi2) Francesca Rapparini2) Dept. of Environmental Sciences, College of Environmental Sciences, Peking University, Beijing, 100871; ) ISTEA-CNR Via Gobetti 101, 40129 Bologna, Italy)
The emission characteristics, emission rate and its diurnal variation of one of the main Mediterranean macchia (Pistacia lentiscus) in Noak’s Ark reserve, Sardinia, Italy have been studied using Dynamic Sampling and GC-MS method. Compounds such as α-pinene,β-pinene, sabinene, Limonene, p-cymene, camp hene, β-phellandrene,β-myrcene, α-terpinene, α-phellandr ene, 3-carene and isoprene were investigated. The emissions of the terpenes account for 99.4% of the total emission, while th e emission of isoprene only accounts for 0.6%. Of all the terpenes, the main emit ted compounds are α-pinene, β-pinene, sabinene and Limonene, which account for 64 .5%、18.4%、6.0% and 5.9% of the total emission respectively. The emission r ates of terpenes increase with temperature, showing a positive exponential correlati o n. Under normal state (temperature of 303?K), the emission rate of Pistacia l enti scus is 2.72±0.72?μg/g(DW)·h. It’s determined that β value of Pi stacia lentiscu s in its emission rate formula is 0.128?K-1, which is in good agreem ent with the values (0.057～0.144?K-1) in the literature.