CONICET | Buscador de Institutos y Recursos Humanos

Forest loss can affect ecosystem processes such aslitter decomposition. In semi-arid areas, where forest loss is increasing, soilfauna can play a particularly important role on litter decomposition. However,few studies have addressed the effect of soil fauna on litter decomposition infragmented semi-arid forests, and none within the dry season in which mostlitter is shed. In this study, we employed litterbags filled with a common substrate to assessforest size and invertebrate detritivore effects on decomposition. Our resultsshowed an average 14% litter mass loss along 3-9 months of incubation in the dryseason, with variations being independent of forest size. Although exclusionresulted in slightly lower abundance of invertebrate detritivores, litterdecomposition was similar in exclusion and non-exclusion treatments. We foundno significant relationships between fragment size and invertebrate abundance orrichness, which in turn did not influence decomposition. Temperature or moisturelimitations, and even photodegradation, could have masked differences indecomposition rates related to forest size during the dry season in semi-arid ChacoSerrano. Additionally, harsh environmental conditions during the incubationperiod could constrain the impact of invertebrate detritivores on thedecomposition process. The absence of clear links between forest fragmentation,decomposition and soil fauna during the dry season, when conditions might beparticularly limiting for this process, and when invertebrates could beexpected to play a particularly important role, opens up new questions andhighlights the complexity of this fundamental ecosystem process.