부산대학교 도서관

Biogenic volatile organic compound (BVOC) emissions such as terpenes from varied treespecies are highly reactive and when mixed with anthropogenically emitted nitrogen oxidesact as strong precursors of secondary pollutants such as ozone and secondary organic aerosol,with consequences also for cloud formation and the regional climate. Mahogany (Swieteniamacrophylla King) trees occupy an area of ∼150 million ha, and are widespread in Centraland South America and parts of South Asia. The species is listed in the Convention onInternational Trade in Endangered Species (CITES) of Wild Fauna and Flora AppendixII due to widespread unsustainable logging, and silviculture and agroforestry ofMahogany are increasing globally to keep up with the demand for its highly-valued bestquality timber. However, to the best of our knowledge, its BVOC emissions remainunknown. Here, we quantified the emission flux (EFBV OC) of naturally-growing Mahogany(Swietenia macrophylla King) at a site in North India using a dynamic branch cuvette andrapid VOC measurements made using a high sensitivity proton transfer reaction massspectrometer (PTR-MS). BVOC emissions were studied as a function of temperature,photosynthetically active radiation (PAR) and other physiological factors for a betterunderstanding of the drivers of emission flux. It was found that Swietenia macrophylla Kingemitted very high rates of monoterpenes with highest emissions during the monsoon seasonfollowed by the post-monsoon season and summer season. Surprisingly, significantco-emission of other reactive compounds that have recently been observed in ambientair over tropical rainforests was also observed, and the diurnal variability of themonoterpene flux appeared to be more strongly driven by PAR rather than temperature withpeak hourly values reaching as high as 78 micrograms of monoterpenes/gDW/h. [ABSTRACT FROM AUTHOR]