Effect of reduced-impact logging on seedling recruitment in a neotropical forest

Abstract

Seedling growth and survival are critical for tropical rainforest regeneration. Alterations to natural disturbance regimes, such as those brought about by logging, have the potential to shift relative species abundances and the community composition of forests, resulting in population declines for commercially valuable species. Timber operations therefore need to minimise such changes if long-term sustainability is to be achieved within the industry. Reduced-impact logging (RIL) has been promoted widely as an alternative management strategy to conventional selective logging, as it employs practices that decrease the negative impacts of logging within forests. However, the long-term sustainability of RIL, including the influence it has on the regeneration of species targeted for timber extraction, is still uncertain. Here we undertake a comparative study in Iwokrama forest, Guyana, examining seedling densities of four commercially valuable and two pioneer tree species in unlogged, 1.5years and 4.5years postharvest forest plots to ascertain how seedling regeneration is effected by RIL. We find that RIL had either a neutral or positive impact on the density of seedlings of timber species when compared to unlogged forest, with pioneer species densities remaining rare. We conclude that the forestry practices associated with RIL have little effect on the natural regeneration rates of key commercially valuable tree species in logged neotropical forests.