FOLIAR DECOMPOSITION OF CAATINGA SPECIES IN ALAGOAS

Leaf decomposition is one of the main processes that regulate nutrient cycling. Understanding how the decomposition process occurs makes it easier to understand ecological processes in ecosystems. The aim of this study was to evaluate the leaf decomposition of Byrsonima gardneriana A. Juss, Tocoyema formosa (Cham and Schltl) K. Schum and Tabebuia sp. of Caatinga in Delmiro Gouveia, Alagoas. To evaluate the decomposition, leaves were collected from the three species, oven dried at 65 °C for 72 hours, weighed 15,0 g of leaves and inserted into the litterbags, which were distributed on the soil surface, withdrawing monthly ten per species, which again were dried and weighed for determination of decomposition relative to the initial weight. About the species evaluated during the 300 days, T. formosa presented a higher rate of decomposition, followed by Tabebuia and B. gardneriana; The decomposition of leaf material is influenced directly by rainfall, since when precipitation is higher, decomposition increases; The studied region went through a long period of drought, making it difficult to decompose the leaf material of the species sampled; The carbon and organic matter contents are superior to other Caatinga environments, due to the good conditions of the experimental area, however these variables did not present significant relation with decomposition of the species; The C/N ratio influences the decomposition of species leaf material of T. formosa and Tabebuia; Due to the microclimatic conditions and characteristics of the plant material, B. gardneriana was the slowest decomposing species