Deposition patterns in bulk precipitation and throughfall in a subtropical mixed forest in central-south China

Abstract

The chemistry and deposition pattern in bulk precipitation and throughfall (TF) were examined and evaluated based on the 3-year observations in Shaoshan subtropical deciduous-conifer mixed forest in central-south China. The TF chemistry was notably changed when passing through canopies, which probably was attributed to the dry deposition (DD) on leaf surface and the canopy exchanges. Base cations' (Ca2+, Mg2+ and K+) fluxes were significantly enriched in TF, in particular for K+. The annual K+ canopy exchange was ∼12 times larger than DD, and canopy exchange of Ca2+, Mg2+ and K+ was four times as high as the DD. The canopy exchange of base cations in association with weak acid accounted for 28.4 per cent of total leached base cations, which was one of the important factors to modify the TF chemistry.