Développement méthodologique pour la valorisation bois d'oeuvre d'une ressource forestière donnée : développement d'un outil d'aide à la décision et étude de cas au Cameroun

This work deals with the development of a methodology allowing to globally and consistently consider wood valorisation from a given forest resource. The methodology has been developed for the mostly encountered case in the Congo basin, where forest harvesting and wood processing activities are most often performed by the same company. This approach enables the integration of technical and economic specificity peculiar to each wood species and to logs quality, as weil as their consequences on productivity. Base on a wellknown of wood market, the competitiveness estimation of each kind of wood process by species and by production type, as well as in the specifie conditions of each project constitute a tool for decision making. This tool allows to structure the approach and simulate sorne of the strategie choices that have to be made.The proposed methodology is developing in five steps, with one or more possible feedback : The first step consists in analysing the technical consistence between the available resource and the products which can be produced : from the resource inventory (species, log quality... ) and from the corresponding wood properties, the type of wood products to be manufactured is deterrnined (technical requirements to be met related to intrinsic wood characteristics).The second step consists in performing a rough evaluation of the profitability of the targeted productions for each wood species. The aim is to eliminate non competitive productions and to deterrnine the processing costs of the remaining productions. The third step is a detailed estimation of the profitability by wood species and by production type. This enables the elimination of those of the species which should stay non competitive even after process optimisation.The fourth step corresponds to the use of methods for process optimisation. It is mainly based on the functional analysis concepts applied to wood processes.The fifth step allows the selection of the productions to be kept (slicing, peeling, softwoods sawing, hardwoods sawing ... ), referring to economic and financial analysis of each type of them, completed by strategie aspects. In case of surrender of any type of production, a feedbackallow to make a new evaluation ofthe allocation of the resource.The methodology is further applied to the concrete case of a 80 000 ha forest unit in eastern Cameroon. This work led to assess its operational character as a tool for decision making. Finally, the main limits and proposaIs for future research orientations are presented : absolute necessary increase in the accuracy ofresource evaluation (quantity and quality), development of a software for assistance and capitalisation, integration of recently developed methods and concepts from innovation management, fromstrategie decision making on marketed products, adaptation of the methodology to other types of forest sector organisation.
Une méthodologie globale et cohérente de raisonnement de la valorisation du bois d'oeuvre d'une forêt donnée est développée. La méthodologie intègre les aspects techniques, économiques et stratégiques au niveau première transformation. Elle est développée en 5 étapes avec possibilités de feed-back : déterminer au plan technique quels types de produits peuvent être fabriqués, estimer la rentabilité par filière de première transformation (tranchage, déroulage, sciage), estimer la rentabilité par essence et par filière afin d'écarter celles nettement déficitaires, optimiser les procédés de transformation, sélectionner les filières en s'appuyant sur l'analyse économique et financière. Une étude de cas est réalisée sur une forêt au Cameroun. La poursuite de la recherche devrait s'attacher à obtenir une meilleure précision de l'évaluation de la ressource, intégrer des outils méthodologiques complémentaires, créer un support informatique et adapter la méthodologie à d'autres cas concrets.