Search

Abstract: The forest growth model 4C was used to investigate how conversion management of a Scots pine (Pinus sylvestris L.) stand towards a mixed oak–birch stand would affect stand structural development – and hence biodiversity and productivity – in the long term. For this purpose the 4C model was parameterised for natural regeneration of light demanding species and extended for management of multi-layered stands. A series of structural indicators was selected to describe key factors of forest biodiversity at the stand scale. Two consecutive aspects of Scots pine conversion were tested: (1) the choice of conversion strategy between thinning and gap creation and (2) the choice of conversion regime in terms of cutting cycle, thinning type and pine tree retention. Three simulated conversion strategies aim at the gradual removal of the pine canopy but differ in the spatial organisation of pine cuttings and hence result in different light conditions for regeneration. Only the directed gap creation strategy was able to maintain and increase birch admixture to the stand and to approach natural stand structural development. Simulation of 12 conversion regimes for the directed gap creation strategy indicated that thinning type (from above or from below), pine tree retention at final felling (50% of the standing volume or none) and cutting cycle (6, 9 or 12 years) all significantly influence stand structural development. These effects were clearest for oak development. Birch occurred in a few mixed clusters, but tended to disappear when longer cutting cycles were used. Based on a multi-criteria analysis we conclude that the optimal conversion regime – in which both stand productivity and biodiversity objectives can be combined – implies thinning from above, pine tree retention, and cutting cycles of 6 years. The conceptual validity of the model as well as the applicability of the results are discussed. [Copyright &y& Elsevier]

• We propose a framework for the optimal supply of forest biodiversity. • We define optimal wood and biodiversity streams to maximize social welfare. • Climate change has important implications for biodiversity-oriented policy mechanisms. • Current management undersupplies biodiversity and is inefficient under climate change. Forest biodiversity underpins social welfare by preserving ecosystem multifunctionality and the provision of ecosystem goods and services. Still, the social value of biodiversity is not adequately incorporated into forest management and decision support models. This study proposes a novel approach for defining socially optimal biodiversity levels, wood supply and taxation schemes under climate change. We developed a partial equilibrium model to maximize consumers' and producers' surplus until the end of the century, including climate change impacts as productivity shocks in a coupled ecological-economic framework. In our model, we consider a first-best and a second-best taxation scheme to internalize the value of forest biodiversity into forest planning. The framework developed here was applied to a temperate forest landscape in southwestern Germany, where biodiversity has a high social value. Our results indicate an increasing consumption of wood and supply of biodiversity (up to 38.4 %) until the end of the century. Moreover, climate change may affect forest productivity, optimal harvesting rates and taxation schemes. Crucially, current management is unable to capture the adequate social value of biodiversity and is inefficient under climate change. Policy mechanisms are therefore required to correct biodiversity provision in temperate forest landscapes. [ABSTRACT FROM AUTHOR]