The seasonal cycle of stem variations in beech populations is affected by interannual fluctuation of climatic conditions more than by the tree origin

Abstract

European beech (Fagus sylvatica L.) is highly sensitive to climatic fluctuations, and its distribution is expected to be affected by the projected climate change. In our study, we applied high-resolution stem size variation measurements to understand the effect of provenance and season on the variability in phenotypic plasticity between and within marginal beech populations. Four marginal beech populations were selected among those growing in common garden experiment in Oleszyce, Southeastern Poland. Stem circumference variation were recorded by automatic band dendrometers during 2016 – 2018. Our results highlighted the key importance of climatic conditions, namely temperature and precipitation of August as well as temperature of June and precipitation of April for stem size variation, but the effect of provenance was scares. Temperature of spring and temperature with precipitation of autumn affect onset and end of stem size variation. Thus, high intra-provenance variation in stem size changes suggests that local populations will cope with climate anomalies thanks to relatively high adaptive potential.