A Multi-layer model for estimating sulfur dioxide deposition to a deciduous oak forest canopy

Abstract

A multi-layer 'K-theory' model for gaseous deposition to a deciduous forest is described and discussed. The model incorporates realistic physiological concepts to improve upon earlier multi-layer models found in the literature. Computations of deposition fluxes and velocities are most sensitive to variations in parameters relating to stomatal resistance. The model computations of deposition velocities are less sensitive to aerodynamic parameters since the canopy resistance of a deciduous forest is generally much greater than the aerodynamic resistance. Model computations of SO2 flux and deposition velocities are tested against deposition measurements made over a deciduous forest; these computations are not significantly different from measured values. Estimates of deposition fluxes, computed with multi-layer model, improve upon those values estimated with a "big-leaf" model.