This study was conducted in an area of Amazonia-Cerado transition forest in the noirth of Mato Grosso state, Brazil. The main objectives of the study was to quantify the variability of litter fall and litter pool biomass (leaves, flowers, fruits, and wood), and the participation of the leaves in the return of nitrogen, phosphorus and carbon to the soil through decomposition. Litter was collected monthly during one year and leaves decomposition was analyzed during the dry and rainy seasons. Litter fall varied along the year with higher values in the dry season and predominance of the leaf fraction. Nevertheless, there was no significant difference between dry and rainy seasons for litter pool as well as significant correlation between litter pool and litter fall. Decomposition of leaves was more intense in the rainy season in order of decreasing species: T. schomburgkii, Thyrsodium sp, B. lactescens and P. sagotianum. The species P. sagotianum in both dry and rainy seasons showed most slowly decomposition. The potential return was 70.3 kg.ha-1.year-1for nitrogen, 76.1 kg.ha-1.years-1 for phosphorus, 3.5 ton.ha-1.years-1 for carbon. There was significant correlation between leave decomposition and nitrogen and phosphorus return for all species analyzed in the dry season. However, it was found significant correlation only for the carbon and the nitrogen for the species P. sagotianum in the rainy season.
Nutrients cycling; Litter fall and litter pool; transition forest