SCREENING OF 18 MEDITERRANEAN PLANT-SPECIES FOR VOLATILE ORGANIC-COMPOUND EMISSIONS

Eighteen tree and shrub species were screened for emissions of isopren e and other volatile organic compounds (VOCs) at three locations at Ca stelporziano (Italy) using a bag-enclosure sampling method followed by GC analysis. Thirty emitted compounds were identified. Temperature se nsitivity of emissions of monoterpenes varied between species. Strong temperature dependencies were found for isoprene emissions. For monote rpene-emitting plant species with greatest ground cover in the dunes a nd macchia habitats, alpha-pinene, beta-pinene and sabinene appeared t o be the most frequently and abundantly emitted compounds. Isoprene wa s the major emission from the shrub species screened in the forest. Em issions from four dominant plant species were scaled up to estimate to tal fluxes from the dunes and macchia over a daytime period. Species w ith greatest biomass but low emission rates made a substantial contrib ution to total emissions. (C) 1997 Elsevier Science Ltd.