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

Abstract

Forest management for timber production has improved in tropical forests with the adoption of a polycyclic 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 2×2m 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.