摘要 : Reduced-impact logging (RIL) is a set of techniques aimed to maintain forest structure and functions of the harvested forest as similar as possible to pre-logging status, while reducing adverse impacts from logging activity on the... 展开 Reduced-impact logging (RIL) is a set of techniques aimed to maintain forest structure and functions of the harvested forest as similar as possible to pre-logging status, while reducing adverse impacts from logging activity on the remaining forest. We analysed the mid-term effects of RIL on the regeneration of the long-lived pioneers (LLP) <i>Bagassa guianensis</i> and <i>Jacaranda copaia</i>; the partially shade tolerant (PST) <i>Hymenaea courbaril</i>, <i>Dipteryx odorata</i>, and <i>Carapa guianensis</i> and the total shade tolerant species (TST) <i>Symphonia globulifera</i> and <i>Manilkara huberi</i>. This study was carried out in an intensive study plot in the 600,000-ha Tapajos National Forest, Eastern Amazon - Brazil (03 degrees 02'S and 54 degrees 56'W). Three transects split in 10x10 m plots, adding up to 2.37 ha were sampled in an area where RIL was applied, and compared with a same size sampling in an unlogged area. The regeneration of individuals <= 20 cm in dbh was inventoried and measured before logging in 2003 and three times after logging (2004, 2006, and 2009). RIL modified the forest structure creating more gap-phase plots, with the consequences of such disturbance still remaining after 6 years. Densities of <i>B. guianensis</i>, <i>J. copaia</i>, and <i>S. globulifera</i> increased, while <i>C. guianensis</i> diminished. The positive effect on the density of LLP species was, however, ephemeral and disappeared 2 years after logging. RIL had a positive effect on the height growth rate of <i>S. globulifera</i> and on the dbh growth rate of <i>C. guianensis</i>. Plants growing in the gap-phase plots had higher height growth rates (ANOVA, <i>F</i>_2;2980=33.3, <i>p</i><0.001) than plants growing in other phases, but the same difference was not observed for dbh growth rates (ANOVA, <i>F</i>_1;364=0.9, <i>p</i>=0.33). Crown position had positive effects on height and dbh growth rates: the higher the crown position, the faster the plant grows in height (ANOVA, <i>F</i>_3;2979=148.4, <i>p</i><0.001) and dbh (ANOVA, <i>F</i>_3;362=26.1, <i>p</i><0.001). The application of RIL following the Brazilian regulations, may be considered a silvicultural technique for increasing density and growth rates of commercial species, but additional silvicultural interventions, as liberation for example, might be required for maintaining the ecological outcomes of RIL in the long run.Digital Object Identifier http://dx.doi.org/10.1016/j.foreco.2012.02.028 收起