Análise da relação da riqueza de espécies arbóreas sobre a taxa de decomposição em um experimento de restauração ativa da Mata Atlântica

Abstract

Tropical forests are complex ecosystems with high biotic and abiotic diversity that provide ecosystem functions crucial to their functioning. Taxonomic diversity, influenced by species richness and abundance, impacts ecosystem functions such as nutrient cycling and litter production. It also influences functional complementarity between tree species, optimizing the use of resources and the provision of ecosystem services. The decomposition of litter is an essential process for nutrient cycling, involving a reduction in the mass of organic matter (OM) and the release of nutrients into the soil. This process consists of leaching, fragmentation and chemical alteration of the OM, until its complete mineralization. The litter deposited in the soil can show different decomposition rates depending on factors such as the quality of the OM, the moisture content of the soil, the composition of organisms, among others. It has a labile rapidly decomposing fraction and a recalcitrant fraction that contributes to carbon sequestration and soil properties. The soil influences decomposition and nutrient retention. Environmental degradation caused by agricultural and pastoral activities alters the nutrient cycle and decomposition conditions. Forest restoration with high biological diversity is crucial for re-establishing ecosystem functions and soil fertility. The aim of this study was to analyze the influence of tree species richness on the rate of litter decomposition in areas of a restoration experiment. It was observed that, in the initial periods of the restoration experiment (i.e. less than 2 years), species richness had no significant influence on the decomposition rate. Thus, longer periods are needed to evaluate this relationship over time and a better understanding of the influence of other environmental factors that may mask the effect of species richness on decomposition.