Identification and quantification of volatile organic compounds found in a eucalyptus forest during FIELDVOC'94 in Portugal

A field campaign was carried out in a eucalyptus forest in Portugal to identify and quantify ambient VOCs in a rural area, with the emphasis on isoprene and it's reaction products. In conjunction with this study, the higher molecular weight VOCs were also investigated. In total, 53 higher molecular weight compounds were identified at the site, 44 of which were quantified and found to be between 0.002 and 8 ppbv. The range of compounds found suggested that there were both biogenic and anthropogenic sources of VOCs, which indicated that transport effects were of importance at the site. A definite diurnal variation of the monoterpenes was observed. Comparison of the ambient levels of the monoterpenes with emission data from the eucalyptus obtained at the site suggested that there was a source other than the eucalyptus trees for monoterpenes.