Changes of vascular plant diversity along a chronosequence of beech coppice stands, central Apennines, Italy.

摘要

This research sought to understand the patterns of vegetation recovery after disturbances because of coppice management in beech forests. Eighty sampling units from the mountain belt of the Marche region (Apennines, Italy) were collected according to a stratified sampling based on their geological setting (limestone, sandstone), elevation classes and age after last coppicing (to represent a chronosequence, from 1 to 90 years). The expected successional trend of decreasing species richness was confirmed, together with some stabilisation processes for older stand ages. However, more complex diversity patterns were found when total species richness was decomposed into the species richness of five social behaviour types (SBTs), defined based on the species' habitat preference. On both bedrocks, temporal gradients explained the observed diversity changes at the stand level: forest specialists increased whereas non-forest species decreased. A relatively long time after coppicing (40-60 years), the contribution of the beech specialist species doubled, whereas non-forest and species from anthropogenic habitats decreased by about 50%. On sandstone, the contribution of gap species also decreased over a long-period, and the beech stands experienced stronger changes over time. We conclude that the decomposition of total species richness in terms of SBT affords the opportunity to identify temporal references for thresholds which can be used to assess plant diversity status in relation to management schedules and conservation policy decisions.