A ocorrência de fogo media a remoção de sementes por pequenos roedores em habitats florestais neotropicais

(Fire occurrence mediates small rodent seed removal in neotropical forested habitats) Fire can alter animal-plant interactions such as seed dispersal and seed predation. However, little is known about the long-term effects (≥ 2 years) of a fire event on these ecological processes. We investigated the relation between fire and small-rodent removal upon seeds of six tree species in Gallery Forests from Brazilian savanna (Cerrado). We expected a reduction in rodent abundance and a consequent reduction in total number of seeds removed in burned areas. The relative role of small rodents as seed removers, however, should increase in such areas, due to a possibly stronger negative effect of fire on larger seedeating animals. We sampled eight forested areas (four burned 2.8 years before and four that had not been burnt) for evaluation of small-rodent communities (3,789 trapping nights). We also assessed the role of small rodents as seed removers using two exclusion treatments: semipermeable exclosure (exclusive access of small rodents) and an open control (access of all seed-removing animals) (34 experimental stations per area). As expected, the average abundance of rodents in the burned forests was reduced to about 1/6 in comparison to the unburned ones and overall seed removal was significantly reduced in fire-disturbed forests for the six species. We found no effects of Treatment (or Fire x Treament) for the seeds of Copaifera langsdorffii, Hymenaea courbaril, and Mauritia flexuosa, indicating that small rodents were the main seed removers regardless the fire occurrence. For Cariniana estrellensis and Dipteryx alata, seeds from open stations were significantly more removed than in exclosures, indicating that others animals than small-rodents also were relevant seed removers. Only for Platypodium elegans, the relative role of small-rodents as seed removers increased after fire, as predicted. Fire reduced rates of seed removal by small-rodents in Gallery Forests. Nevertheless, this disturbance event may reduce rates of seed dispersal by reducing seed removal by potential dispersers in comparison with small rodents, which act chiefly as seed predators. Key-words: Small rodents, seed removal, fire, Gallery Forests, Cerrado.