Growth responses to climate and drought in silver fir (Abies alba) along an altitudinal gradient in southern Kosovo

Abstract

This paper deals with the response of silver fir ( Abies alba Mill.) growth to climate, mainly drought, presenting data from southern Kosovo, for which only little information is available. Two cores from 55 dominant trees were extracted at two sites representing the limits of the natural distribution of silver fir. We built 80- and 112-year-long chronologies for each site. Comparison of both ring width chronologies showed that they were diverse. Pointer year analysis indicated that high spring temperatures and ample rainfall (1082 mm) influenced positively silver fir growth (wide ring), while low spring temperatures and scarce precipitation had an inverse effect. Bootstrapped response functions confirmed that April and May temperatures of the current growth year influenced positively silver fir growth at the low-elevation site, while the July precipitation of the previous growth year had a negative influence. At the high-elevation site, warm previous December temperatures had a positive influence on silver fir growth. Drought indices indicated two periods (1953–1961 and 1994–2001) with moderate drought. Correlation analysis between silver fir radial growth and drought indices revealed that the impact of drought on radial growth was significant at the time scale of 1.5 months during the summer months.