Long-term effects of traditional and conservation-oriented forest management on the distribution of vertebrates in Mediterranean forests: A hierarchical hybrid modelling approach

Abstract

Aim: Recently, increasing attention has been devoted to the development of sustainable forestry practices aimed at finding a balance between the maintenance and enhancement of different forest resources. However, the long-term, large-scale effects of conservation-oriented forest management on vertebrates have been poorly studied. We tested the hypothesis that conservation-oriented forest management, being conceived to mimic the dynamics of a natural forest succession more closely than does traditional forestry, causes a less severe long-term impact on the distribution of forest vertebrates. Location: Molise region, Central Italy. Methods: We proposed a hybrid modelling framework based on the integration of a forest dynamic model ('LANDIS-II') with species distribution models (SDMs). The framework was applied on four forest specialist vertebrates (tiny salamander, slow worm, Eurasian nuthatch and Leisler's bat) and included three components: forest dynamic model (FDM), SDMs and spatial pattern analysis (SPA). FDM was used to simulate spatially explicit patterns of forest succession for the current time and for 2050, imposing three alternative forestry scenarios. The simulated forest succession patterns were analysed through SPA to calculate spatialized landscape metrics that were adopted as environmental predictors for SDMs. Landscape trajectories were calculated on current and future species distributions predicted with SDMs to evaluate the effect of alternative forestry practices on their extent and fragmentation. Results: Forest management mainly affected the spatial configuration rather than the extent of the species potential distributions. Conservation-oriented forest management was more favourable than traditional forestry in increasing the extent and reducing the fragmentation of the studied species' distributions. Main conclusions: Conservation-oriented forest management, by mimicking the dynamics of a natural forest succession more closely than did traditional practices, favoured elements, such as forest unevenness, species richness, aggregation of patches and variability in their distances, which emerged as fundamental characteristics for preserving the long-term persistence of forest vertebrates.