The climate sensitivity of Norway spruce [Picea abies (L.) Karst.] in the southeastern European Alps

To investigate the potential of Norway spruce (Picea abies L. Karst) as a palaeoclimate archive in the southeastern European Alps, tree ring chronologies were developed from trees growing at two sites in Slovenia which differed in their ecological and climatological characteristics. Ring width, maximum latewood density, annual height increment and latewood cellulose carbon isotope composition were determined at both sites and the resulting time-series compared with and verified against instrumental climate data for their common period (AD 1960-AD 2002). Results indicate that ring width sensitivity to summer temperature is very site-dependent, with opposing responses at alpine and lowland sites. Maximum density responds to September temperatures, indicating lignification after cell division has ceased. Stable carbon isotopes have most potential, responding strongly to summer temperature in both alpine and lowland stands. Height increment appears relatively insensitive to climate, and is likely to be dominated by local stand dynamics.