Effects of termite exclusion on decay of a high-density wood in tropical rain forests of Peninsular Malaysia

The effect of excluding termites on wood decay was evaluated in two tropica l lowland rain forests in West Malaysia. Billets from the tree, Paranepheli um macrophyllum King (Sapindaceae), were placed in either of two designs of lidless stainless-steel trays on the forest floor. The control trays had o penings at the bottom and lower sides while the trays designed to exclude t ermites had the openings covered with stainless-steel mesh. The loss rates of carbon, nitrogen and phosphorus, and the ratios of carbon/nitrogen and c arbon/phosphorus, were compared for wood samples from which termites had or had not been excluded. Comparisons were made at yearly intervals over a pe riod of three years. C, N and P were lost over two or three years. The C/N ratio declined over the experimental period, indicating a slower loss of N compared with C. There was a significant difference in the C/N ratios of th e wood samples between the two types of trays for one of the forest sites; the ratio was greater when termites were not excluded, indicating that the termites had enhanced nitrogen release from the decaying wood. The advantag e of the present termite exclusion method over other methods is discussed.