DOI: 10.5061/dryad.6c886
title: Data from: Present conditions may mediate the legacy effect of past land-use changes on species richness and composition of above- and below-ground assemblages

description: 1. In forest ecosystems, the influence of landscape history on
 contemporary biodiversity patterns has been shown to provide a convenient
 framework to explain shifts in plant assemblages. However, very few
 studies have controlled for present human-induced activities when
 analyzing the effect of forest continuity on community structures. By
 cutting and removing trees, foresters substantially change stand
 ecological conditions, with consequences on biodiversity patterns.
 Disentangling the effect of past and present human activities on
 biodiversity is thus crucial for ecosystem management and conservation. 2.
 We explored the response of plant and springtail species richness and
 composition to forest continuity (ancient vs recent) in montane forests,
 while controlling for stand maturity (mature vs overmature). We
 established 70 sites in landscapes dominated by unfragmented ancient
 forests where we surveyed plants and assessed springtails by analyzing
 environmental DNA. 3. Neither plant nor springtail species richness was
 influenced by forest continuity or by stand maturity. Instead,
 site-specific characteristics, especially soil properties and canopy
 openness, were of major importance in shaping above- and below-ground
 richness. 4. For plant and springtail species composition, the effect of
 forest continuity was mediated by stand maturity. Thus, both plants and
 springtails showed a convergence in assemblage patterns with the
 increasing availability of overmature stand attributes. Moreover, soil and
 stand-scale factors were evidently more important than landscape-scale
 factors in shaping above- and below-ground species composition. 5.
 Synthesis. We clearly demonstrated that biodiversity patterns are more
 strongly influenced by present human-induced activities than by past
 human-induced activities. In the Northern Alps where our study sites were
 located, the colonization credit of most species has been paid off and the
 transient biodiversity deficit usually related to forest continuity has
 moved toward equilibrium. These findings emphasize the necessity to better
 control for local-scale factors when analyzing the response of
 biodiversity to forest continuity; we call for more research into the
 effects of forest continuity in unfragmented mountain forests.
description: Environmental
 variablesDate were collected in
 70 beech-fir montane forests of the French Northern Alps, in 2014 (stand
 measurements) and 2015 (soil measurements). Abbreviated headlines are as
 follows: "H_index" = Humus index (based on humus form);
 "pH" = pH-H2O (topsoil); "CN_ratio" = Total carbon /
 total nitrogen ratio (topsoil); "Canop" = Mean canopy openness
 (%); "Tree_Compo" = Coniferous proportion;
 "Tree_Struc" = Number of diameter classes of standing trees ;
 "Alpha_LU" = Land-use diversity (500 m radius);
 "Dist_Forest" = Distance to forest edge in meters;
 "Prop_Forest" = Forest proportion (500 m
 radius).Data_Plots.csvHerbaceous plants dataSite by species matrix of herbaceous plants (presence/absence).Data_Plants.csvSpringtails dataSite by species matrix of springtail MOTUs (presence/absence).Data_Springtails.csv