Natural regeneration of tree species in the Eastern Amazon: Short-term responses after reduced-impact logging

Forest management for timber production has improved in tropical forests with the adoption of a poly cyclic silvicultural system (PSS) where harvesting is carried out using reduced-impact logging (RIL). In this study, the natural regeneration of forests harvested under RIL restrictions was assessed in three different sites of the Eastern Amazon two years after logging. A total of 7987 seedlings and saplings belonging to 197 species were sampled through 951 plots of 2 x 2 m in 11 different natural and logging created environments. Light-demanding commercial species presented their highest density in logging environments such as logging gaps, skid trails, and borders of log decks. Shade-tolerant commercial species were more common in natural and logging gaps. Regarding the densities of harvested species in the three study sites, only 26.3% were represented by >= 5 individuals and 28.1% were completely absent in the surveys two years after logging. These results suggest a lack of natural regeneration of the current commercial tree species in the Eastern Amazon. Therefore, post-harvesting silvicultural treatments as enrichment planting and the tending of the natural regeneration in logging gaps should be applied to ensure the regeneration of these species. (C) 2016 Elsevier 13.V. All rights reserved.