At the TRACE conference organized between 11-15 May 2016 in Białowieża (Poland) we presented results of our investigation intra-specific plasticity in common beech (Fagus sylvatica L.) trees growing in favourable, yet different climatic conditions in Slovenia. Dynamics of xylem differentiation processes as well as vascular characteristics were investigated in order to evaluate how beech trees adjust their xylem structure to changing environmental regimes. Analyses were performed on micro-cores collected at weekly intervals at Menina planina (ME – 1200 m a.s.l.) and Panska reka (PA – 400 m a.s.l.) between the 2008–2011 growth seasons. Time intervals between major cell differentiation steps were investigated in the initial and terminal parts of the xylem increments; , i.e., onset / end of (i) cell expansion (PC), (ii) wall thickening and lignification (SW), and (iii) fully matured cells (MT). In addition, vessel characteristics (density, diameter, mean area, and total conductivity area) were analysed in the first and last quarters of the growth rings. Results showed that although the duration of the growing seasons was much longer at PA than at ME, the time differences between first observed PC and SW cells as well as between first SW and MT cells were similar at both sites. At the end of the growing seasons the time intervals between the cessation of PC and MT phases significantly differed between sites. We observed differences in xylem differentiation dynamics in the initial and terminal part of the growth rings which are partly reflected in differences of vessel features in beech. Vessel density was the only vessel characteristics that significantly differed between sites and was therefore suggested to be a promising climatic proxy, whereas other vessel features seemed to be predominantly intrinsically controlled.
B.06 Other
COBISS.SI-ID: 4404390