Msc project: Study of low impact logging on the Manare Saut Lavillette site with a forest simulator

Authors: Lagrange Benjamin, Kratz Fanny

Supervisors: Sylvain Schmitt, Guillaume Salzet, Melaine Aubry-Kientz

Abstract: As the demand of timber is expected to increase over the years as the global population explodes, the logging activity has to achieve the best management strategy to keep its forests resilient. Forest dynamics simulators, such as TROLL, can simulate the regeneration of a community according to the functional traits of each individual based on its species. We simulated a logging activity through the package LoggingLab on a simulated forest, which was inspired by an inventory done in the Manar´ e Saut Lavilette plot in French Guiana. The simulation has been repeated over four logging cycles, with one cycle consisting in the logging activity followed by a standard period of 65 years of regeneration. To better understand the forest dynamics after logging, harvested volume, metrics of productivity and diversity of the forest have been calculated. The aim of this study was to evaluate the resilience of a forest managed by the ONF with a Reduced Impact Logging protocol (RIL). We observed that after the first logging campaign, the volume of timber decreased, which can be explained by the decrease in the average Diameter Breast Height of timbers. A small impact on the Net Primary Productivity and Above Ground Biomass have been observed over the simulations. The diametric structure of five commercial species (Dicorynia guianensis, Sextonia rubra, Vouacapoua americana, Manilkara bidentata, Goupia glabra) changed into a new pattern with less stems over 55 cm of DBH. This study promotes the diversity of logged trees and improves the knowledge of forest management in the new ecological and socio-economic context which is coming.