Ecological mechanisms of canopy thinning: Insights into biodiversity recovery in neglected coppice

Abstract

Abandonment of traditional management is among the major causes of the loss of temperate forest biodiversity. While numerous studies highlight the positive impact of restoring traditional forest management on biodiversity, there is a notable gap in research focusing on the ecological mechanisms underlying the benefits to taxonomic, functional, and phylogenetic diversity.

In this study, we applied canopy thinning of various intensity in an abandoned coppice to examine the response of vascular plant, ant, carabid and spider communities to the thinning intensity.

Our results showed that the increase of functional diversity following canopy thinning is driven by the increased presence, rather than abundance, of species exhibiting unique combinations of ecological traits. Plant and invertebrate communities were not clustered or overdispersed within the phylogenetic or functional space delimited by the species pool, indicating the dominant effect of stochastic processes on community assembly.

Our multispecies study demonstrates for the first time that ecological mechanism maintaining biodiversity following forest thinning are mainly governed by stochastic processes. Notably, our research reveals that the increase in species richness after tree thinning is due to the presence of species with unique ecological trait combinations. Furthermore, we identified distinct mechanisms driving community changes: carabid beetles and ants mainly experience shifts in species composition, while plants and spiders are more affected by species loss.