Silviculture-driven vegetation change in a European temperate deciduous forest

Forest management consists in anthropogenic disturbances that are able to modulate ecological features, resource availability and successional patterns. Plant communities are thus expected to react differently to contrasted silvicultural systems. We compared plant species composition between stands submitted to a traditional management since many centuries (i.e. coppice-with-standards treatment, stands intensively but infrequently disturbed) and stands recently converted into a selective cutting system (stands moderately but frequently disturbed), over uniform edaphic and topographic conditions. We found significant differences in species composition between both systems. Despite a strong shift in species composition among different stages of the coppice cycle, coppice-with-standards stands supported the highest number of true forest species. Selectively-cut stands were more homogeneous and characterized by ruderal "generalist" species. These fast changes in vegetation composition were related to differences in a group of factors that are directly or indirectly linked to the silviculture-associated disturbance regime, including soil moisture, soil fertility, forest microclimate, light and game predation. We conclude that the conversion of a silvicultural system which has patterned plant communities since many centuries, induces early major changes in vegetation composition. The most negatively impacted species are the so-called "true forest species" that may be better labelled "coppice-woodland species" La sylviculture est une perturbation anthropogène capable de moduler les facteurs environnementaux, la disponibilité des ressources et la dynamique forestière. La végétation spontanée est donc susceptible de réagir différemment à des systèmes sylviculturaux contrastés. La composition floristique de parcelles forestières traitées en taillis-sous-futaie depuis plusieurs siècles a été comparée à celle de parcelles récemment converties en futaie irrégulière coupée « pied-à-pied », en conditions édaphique et topographique uniformes. Malgré des différences importantes en fonction du temps écoulé depuis la dernière coupe, la partie de la forêt traitée en taillis-sous-futaie hébergeait un nombre plus important d'espèces forestières. Les parcelles en futaie irrégulière étaient plus homogènes et caractérisées par des espèces rudérales « généralistes ». Ces changements précoces de la composition spécifique ont pu être reliés à des modifications du contexte environneme