Vertical fluxes of monoterpenes above a Scots pine stand in the boreal vegetation zone

The vertical fluxes of monoterpenes, measured above a boreal forest canopy by a micrometeorological gradient method during two days in summer 1997, ar e presented. The forest, composed mainly of Scots pine (Pinus sylvestris), emitted significant amounts of monoterpenes, alpha-pinene and Delta(3)-care ne being the major species. The correlations of measured monoterpene fluxes with several meteorological parameters are presented. The best correlation was found with the IR radiation temperature of the canopy. The temperature dependency of the monoterpene fluxes, obtained from the measurements, was beta=0.20 degrees C-1. The mean total monoterpene emission rates, normalize d to 30 degrees C with temperature coefficients beta=0.09 degrees C-1 and b eta=0.20 degrees C-1, were 190 ng m(-2)s(-1) and 570 ng m(-2)s(-1), respect ively. (C) 1999 Elsevier Science Ltd. All rights reserved.