Breakdown of Ficus fistulosa ( Moraceae) leaves in Hong Kong, with special reference to dynamics of elements and the effects of invertebrate consumers.

Abstract

Mean rate of leaf material weight loss from coarse-mesh (3 mm) bags was 1.82% day -1, c4 times that inside fine-mesh (0.2 mm) bags (0.44% day -1). Breakdown rates varied seasonally, with maximum rates in spring or summer, and were significantly correlated with prevailing temperatures, rainfall of the 2 previous months, and soil moisture content of the previous month. Potassium and Mg were rapidly leached from leaf material throughout the year; concentrations of C, N, P, Ca and Na remained relatively stable. In the absence of macrofauna (inside fine-mesh bags) decomposition rate constants (k) were positively correlated with the mean abundance of mites and Collembola, and well as with total invertebrate abundance. In the presence of macrofauna (inside coarse-mesh bags) decomposition rate constants were positively correlated with isopod and amphipod abundance. -from Authors