Decomposição da serapilheira em áreas de gramíneas na Universidade Federal Rural de Pernambuco

Abstract

The litter is responsible for numerous functions for the balance and dynamics of ecosystems, and may promote the improvement of edaphic characteristics. Its decomposition rate can act as a bioindicator of soil quality, however, it is necessary to standardize the methodologies for obtaining it. The objective of this work was to obtain and compare litter decomposition rates obtained by litter bag and tea bag methods in two areas with grasses at the Federal Rural University of Pernambuco, Recife - PE (Viveiro Florestal and Ceagri II). The following were randomly installed in each study area: 24 litter bags, 10 tea bags containing green tea, 10 tea bags containing rooibos tea and 10 tea bags containing senna tea. Exponential models were adjusted to obtain the rate of decomposition and the half-life estimated for the litter bag and tea bag methods, and the mass loss of rooibos tea and senna tea was compared. The decomposition rates by the litter bag and tea bag method were higher for the UFRPE Forest Nursery area when compared to CEAGRI II, an area with higher humidity, pH and soil density. The decomposition rate by the tea bag method was different from that obtained by the litter bag method. Senna tea has a loss of mass over time similar to rooibos tea, so the possibility of its use in place of rooibos tea, used in the tea bag methodology, but difficult to find in the Brazilian market, cannot be ruled out. The use of a standardized tea bag method, even if potential, requires further studies, considering the differences in environmental conditions and composition of teas, which influence the hydrolyzable fraction and, consequently, litter decomposition.