Litter productivity and leaf litter nutrient return of three native tree species in drained tropical peatland, Riau-Indonesia

Information on litter productivity and its nutrient return of tree species are essential for consideration in selecting tree species. The study was carried out to quantify the litter productivity and macronutrient (N, P and K) deposition through leaf litter to forest floor under 2 - 3 years old three native tree species of tropical peatland forest. Those three species are mahang (Macaranga pruinosa), geronggang (Cratoxylum arborescens) and skubung (Macaranga gigantea). These three native species coincide with one exotic species krassikarpa (Acacia crassicarpa) were planted on the drained tropical peatland in Riau using a randomized completely block design. Litter trap was set up on this experimental plot for litter productivity measurement. Nutrient content of leaf litter was analyzed to quantify the nutrient return. Results showed that the maximum litter productivity and leaf litter nutrient return was found in geronggang. Litter productivity, N return, P return, and K return of this native tree species were 7.04 ton ha(-1)yr(-1), 60.69 kg ha(-1)yr(-1), 10.82 kg ha(-1)yr(-1) and 57.68 kg ha(-1)yr(-1), respectively. These results suggested that forest and land productivity could be better maintained by Cratoxylum arborescens plantation than other native tree species. In terms of litter productivity and leaf litter nutrient return, this species is, therefore, more recommended than Macaranga pruinosa and M. gigantea.