A predictive model of rainfall interception in forests. II. Generalization of the model and comparison with observations in some coniferous and hardwood stands.
A previously published model of rainfall interception by forests was generalized, and elaborated to enable separate calculation of through-fall and stem-flow. Calculated mean interception loss per month was within 10% of the observed means (for periods of from 8 to 18 months) in Pinus nigra, Pseudotsuga menziesii, Picea abies and Carpinus betulus. In an old coppice of Quercus robur mean monthly interception loss was underestimated by 20% and in artificially defoliated plots in the same coppice, by 32%. The correlation coefficient between observed and calculated monthly totals of interception loss was about 0.9 in five of the stands and 0.82 in the defoliated Q. robur. The ability of the model to account for differences in interception loss between different species in the same climate, between the leafy and leafless condition in deciduous stands, and for stem-flow and evaporation from trunks, is discussed.