Differential climate–growth relationships in Abies alba Mill. and Fagus sylvatica L. in Mediterranean mountain forests

Abstract

Pointer year analysis, simple correlations, and response functions were combined in a dendroecological study to evaluate climate–growth relationships over the last century in two Abies alba Mill. and Fagus sylvatica L. mixed stands in Southern Italy mountainous areas. Analyses revealed species-specific attributes at the two study sites, i.e. Molise and Basilicata. Growth divergence between the two species emerged based on three primary climatic drivers, including drought stress and spring warmer temperatures during the current growing season for F. sylvatica, and water availability in the previous growing season for A. alba. However, despite the microclimatic differences between the two study sites, F. sylvatica showed similar climate–growth patterns, while differences were indicated for A. alba, due to its minor susceptibility to drought stress during the current growing season at the Basilicata site. Indeed, at the southernmost geographic limits of A. alba drought avoidance mechanisms were confirmed, consistent with traits considered diagnostic for the species in the Mediterranean region.