Assessing the externalities of timber production

Abstract

Responsible forest policy promotes management that does not impair the multiple uses of forests or decrease their regulative effects and biological diversity. The most important regulative effect of boreal forests is their ability to remove carbon dioxide from the atmosphere. High biological diversity improves the resilience of forest ecosystems and forest-based economies, enhancing the long-term sustainability of forest production. This study developed a method for assessing the performance of forest management in terms of its effects on multiple uses, biodiversity, and carbon sequestration. These externalities were described with 11 indicator variables, which can be calculated for any Finnish forest stand from the current forest inventory data with currently available models and algorithms. The indicator variables were normalized based on the ranges of the indicator variables in Finnish forests on different sites. The forest-level averages of the normalized indicator variables were used to calculate a multiplicative externality score for the forest. The developed method for calculating the forest-wide externality score was used in two forest holdings for alternative silvicultural systems. The case study results suggested that continuous cover management enhances the positive externalities of timber production, as compared to even-aged rotation forestry. Green-tree retention improved the externality score in both silvicultural systems. Maximizing the net present value of timber production in rotation forestry decreased the externality score by about 50% compared to a non-managed forest. The decrease was about 30% smaller in continuous cover forestry.