DEPOSITION OF AEROSOL ON SPEULDER FOREST - ACCUMULATION EXPERIMENTS

The deposition of alkaline and acidic aerosol compounds on a Douglas f ir forest was measured by washing natural and artificial branches and using a certain type of Petri-dish sampler. The results were scaled to deposition on the entire canopy, using data on the Vertical distribut ion of the leaf area index and the wind velocity profile within the ca nopy. The results are, within the uncertainty range of the measurement s, comparable to those of net throughfall measurements corrected for c anopy exchange, except for the results concerning Na and Cl. The calcu lated deposition Velocities are high because of the high LAI and the l arge fraction of alkaline elements within the coarse-aerosol fraction. Theoretical data on aerosol deposition velocity compare well with the experimentally obtained values. Copyright (C) 1996 Elsevier Science L td