Are litterfall and litter decomposition processes indicators of forest regeneration in the neotropics? Insights from a case study in the Brazilian Amazon

Litterfall plays an important role in nutrient cycling and maintenance of soil fertility in terrestrial ecosystems. We gauged the effects of anthropogenic impacts on the production, decomposition and seasonality of litterfall in primary and secondary forests within a tropical landscape of the Brazilian Amazon. We hypothesized that leaf litter quantity and quality would differ in line with forest disturbance and that these changes would translate into dissimilar decomposition rates. If proved, these processes could be used as surrogates for indentifying the ecological status of forest habitats. The obtained results have shown that, in the study area litterfall is reduced and litter decomposition is braked in disturbed habitats when compared with primary and recovered secondary forests. Also, within similar climatic conditions, the litter production and decomposition rates begin to stabilize in mature secondary forests. Our results represent a useful contribution to understand the dynamics of the litterfall and litter decomposition processes in the neotropics. Both processes were correlated and sensitive to disturbance gradients and should used as forest recovery indicators in ecological monitoring and ecological restoration studies.