Decomposition of leaf litter of four native broad-leaved tree species in south China

Abstract

Leaf litter decomposition of Castanopsis fissa, Cinnamomum camphora, Michelia macclurei and Mytilaria laosensis in mixed broad-leaved plantation and pine plantation was studied by the litterbag method for 1 year. Leaf litter decomposition rates of the four species were highest in Cinnamomum camphora, followed by Mytilaria laosensis, Michelia macclurei, and Castanopsis fissa. The decomposition rates of all four species were higher in the mixed than in pine plantation. The decomposition processes of all species followed Olson’s exponential model. The decomposition coefficients (k) of all species were also higher in the mixed plantation and had the same order as the decomposition rates. The nitrogen contents of leaf litter of the different species studied increased initially and then decreased with time. Net release of N only occurred in pine plantation. Potassium contents appeared to decrease first but later increase, and net release was only found in mixed plantation. Calcium, magnesium and boron all showed similar pattern of initial increase followed by later decrease. They all had net release in both mixed and pine plantations. The release of phosphorus varied greatly between species and showed no clear trend.