In planted forest landscapes, semi-natural forest remnants constitute essential habitats for forest biodiversity. However, modifying forest cover to restore these stands and enhance the connectivity among them remains a logistical challenge for forest managers. While hedgerows have been widely studied for their role in promoting biodiversity in agricultural landscapes (i.e., “bocage”), it remains unclear to what extent these interstitial elements, would enhance biodiversity in planted forest landscapes. To address this question, we conducted our study in a homogeneous and monospecific pine plantation landscape in southwestern France, where we compared the diversity of six taxonomic groups in broadleaved hedgerows vs. pine stand edges. We also analysed the effect of the connectivity of hedgerows to semi-natural broadleaved stands and the proportion of broadleaved stands in the landscapes. Beyond species richness and community composition of each taxon, we calculated multidiversity indexes across all groups (using dominant, rare, or forest specialist species). Multidiversity was significantly higher in hedgerows than in pine stand edges. Hedgerows were home to communities with a distinct composition, including a greater abundance of rare species and forest specialist species. Increasing broadleaved cover in the landscape had a negative effect on multidiversity but altered community composition in three out of six groups. The connectivity of hedgerows to broadleaved stands had no significant effect on biodiversity. Preserving or planting broadleaved hedgerows therefore emerges as an effective and practical management method for enhancing biodiversity, particularly of forest specialist species, in pine plantation landscapes.
Plat et al. (Sun,) studied this question.