Abstract
The investigations undertaken in the College of Forestry, Vellanikkara in Kerala to find out the growth behaviour, biomass production and rate of decomposition of leaf biomass of four multi-purpose tree species, viz., Artocarpus integrifolia, Erythrina indica, Albizia falcataria and Artocarpus hirsute revealed that the total and monthly mean height and girth increment was maximum for Albizia falcataria followed by Erythrina indica. Most of the species recorded better growth from June to December while growth was poor during dry periods. With regard to biomass production, A. falcataria recorded the highest value during the entire course of study. The rate of leaf biomass decomposition was generally faster for all the species studied. All the species lost more than 80 per cent of leaf litter biomass within third or fourth fortnights. Rate of decomposition was faster in A. integrifolia while in E. indica it was slow.
A biphasic model of decomposition with a rapid initial phase followed by a slower phase was noticed for all the species. More than half of the litter mass decomposed within 3rd fortnight in the case of all the species under both the study situations. In the present study, initial nitrogen or carbon: nitrogen ratio was not found to be directly related with decay rate. Lignin content of biomass strongly influenced the rate of decomposition. Weather parameters showed a very feeble correlation with rate of decomposition while soil moisture recorded a high positive correlation.
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