Sustaining the joint production of timber and Lactarius mushroom: A case study of a forest management planning unit in Northwestern Turkey

Abstract

Forest management planning focusing on sustainable supply of forest-based services such as wood and Non-Wood Forest Products (NWFPs) is important for the sustainability of forest ecosystems over time. This study explores the development of a mushroom integrated decision support system (ETçAPOptimization) for multiple use forest management planning and for the analysis of long-term effects of different forest management scenarios on the joint production of timber and mushroom. The Decision Support System (DSS) integrates both mushroom and timber production derived from the same forest ecosystem using empirical models for mushroom occurrence and yield as well as for tree growth. The DSS takes further into account the spatial distribution and productivity models of Lactarius deliciosus and Lactarius salmonicolor generated for the Kizilcasu Planning unit in Northwest Turkey. Six different forest management scenarios were considered, each with a different set of objectives, e.g., maximization of both the amount and the income from timber or mushroom production. Some scenarios include further timber even flow constraints (10% fluctuation). The Net Present Value (NPV) and the amount of timber and of mushroom production were used as performance indicators to discuss and elaborate on forest dynamics under different management scenarios. The results indicated that forest management planning strategies to address the maximization of NPV from mushroom production scenarios are characterized by substantial decreases in total income from the forest due mainly to the conservation of forest areas to favor mushroom production. On the other hand, the integration of regulatory constraints into forest management plans lead to a substantial decrease of both the economic profit and the amount of forest ecosystem services, e.g., timber and mushroom. The results showed that the NPV from mushroom production can be two to three times higher than the NPV from timber production based on carefully designed management objectives and constraints.