Functional adjustments of xylem anatomy to climatic variability: insights from long-term Ilex aquifolium tree-ring series

摘要: The present study assessed the effects of climatic conditions on radial growth and functional anatomical traits, including ring width, vessel size, frequency derived variables, i.e., potential hydraulic conductivity xylem vulnerability to cavitation in Ilex aquifolium L. trees using long-term tree-ring time series obtained at two climatically contrasting sites, one mesic site Switzerland (CH) drought-prone Italy (ITA). Relationships were explored by examining different point pattern analysis was applied investigate clustering. We also used generalized additive models bootstrap correlation functions describe temperature precipitation effects. Results indicated modified anatomy over last century; particular, increased markedly both sites recent years, all traits examined, with exception vulnerability, higher CH compared ITA drought site. A significant clustering observed site, which could contribute an enhanced tolerance drought-induced embolism. Flat negative relationships between size width observed, suggesting carbon not allocated under favored stem water conduction. Finally, most cases results that influenced more substantially than tree growth, a crucial role func tional plant acclimation future conditions.