RUPTURE IN A COLLEMBOLA COMMUNITY STRUCTURE FROM A QUERCUS-ROTUNDIFOLIA LAM FOREST DUE TO THE REAFFORESTATION WITH EUCALYPTUS-GLOBULUS LABILL

Here we compare Collembola populations from a Quercus rotundifolia for est and an Eucalyptus globulus plantation. The overall analysis of dat a (using both diversity and similarity measures) have shown clear sign s of rupture on the structure of collembola populations, with the faun a associated with the Quercus stand being richer (in exclusive and pre ferential species) and more abundant than the one connected with the E ucalyptus. Data also reflects the faunal stratification between organi c and mineral horizons, with the majority of species being associated with upper soil layers in detriment of mineral horizon. These disrupti ons may be related to profound alterations of habitat characteristics, particularly the frequent removal of shrub vegetation and leaf layer, result of the forestry practices connected with the preparations and management of the eucalyptus plantation.