A Decision Support System to Assess the Trade-offs Between Timber Production and Ecosystem Services

The 21st century is characterized by a marked increase in public demand to consider the social aspects of forest management, most often as the clear trade-offs between timber production and environmental conservation. In this study, sugi (Cryptomeria japonica D. Don) was estimated forest stand growth. Moreover, five important forest functions, namely, timber production, soil conservation, water resource conservation, carbon storage, and biodiversity conservation were quantitatively assessed, across each forest management unit. The results revealed that the inclusion of constraints related to carbon storage or soil conversation extended the cutting age and increased the area of forest with trees over 120 years of age. The optimized harvest schedules maintained timber production by the regeneration of high-productivity forests, while low-productivity forests on steep slopes were designated for public interest functions. The results proved that the tested approach can successfully take into account the multi-functional nature of forests; in other words, even though timber production decreased, the indicators of certain important public interest functions improved over the study period. This approach can be used to formulate schedules that take into account both national- and local-level regulations and enable forest managers to compare economic performance with environmental gains.