Regeneration and management of lesser known timber species in the Peruvian Amazon following disturbance by logging

Following the principles of Reduced Impact Logging (RIL) the construction of roads and log landings together with logging gaps are the most profound direct impacts that a forest operation has on the forest. While the effects of logging gaps have been studied in detail, the impacts of road and log landing construction, and how the forest regenerates after such disturbances, remain poorly understood. This paper investigates the regeneration success of a range of well/lesser-known timber species in a tierra-firme forest concession in Peru. Sample plots (100 m2) were established in areas with three different types of logging induced disturbances: skid trails caused by log extraction, secondary roads and log landings/patios. Seedling establishment of 16 different commercially targeted species groups was examined for these three types of disturbances using a chronosequence of 5 years. As 100 plots were inventoried for each type of disturbance an area of 3 hectares was sampled in total. The regenerative success was compared across disturbance categories, and each species' response to environmental variables was investigated using zero-inflated negative binomial regression. Regenerative success varied across species groups, with the majority either regenerating significantly better at the least disturbed sites (n = 6) or showing statistically indistinguishable results (n = 9) because of limited regeneration. One species group, Cariniana spp., regenerated best at intermediate sites. The varying response across species groups indicates a need for a more varied forest management. For species with poor regeneration it is recommended to plant saplings (enrichment planting) to ensure forest recovery and species preservation at the landscape level.