Contribution of forest management artefacts to plant diversity at a forest scale

Abstract

Most temperate forests are managed for wood production, and some forestry practices generate typical environmental features such as roads, paths, ditches and tractor ruts, which are likely to affect forest species distribution. We studied the influence of forestry artefacts on the overall forest-understory plant diversity in an ancient oak-dominated French forest with a long history of management. Two designs (grid design and paired design) were built in order to record the occurrence frequency of artefacts and to estimate the originality of the plant assemblage that they host. We recorded 897 plots on the grid design: 68.3% of the plots were more than 4 m away from any artefact, 23.3% were within 4 m of an artefact and 8.4% were located on an artefact. The artefact contribution to total floristic richness would lie between 8.0% and 22.6%, depending on whether the artefact surroundings were included or not in the artefact contribution. Road verges were the least frequent artefacts but provided the richest contribution to overall plant diversity (82%), whereas paths were the poorest (with only a 42% contribution). Thirteen species appeared to prefer artefacts over control plots: six forest species, five non-forest species and two generalist species. We show that forestry artefacts are key components of the floristic diversity in managed forests; therefore, forest management should take them into consideration.