Author(s):
1. Branko Stajiić, University of Belgrade-Faculty of Forestry, , Serbia
2. Marko Kazimirović, University of Belgrade-Faculty of Forestry, , Serbia
3. Vojislav Dukić, Šumarski fakultet Banja Luka , Republic of Srpska, Bosnia and Herzegovina
4. Živan Janjatović, University of Belgrade-Faculty of Forestry, , Serbia

Abstract:
To understand how European ash (Fraxinus excelsior L.) in the area of NP ’’Djerdap’’ might respond to environmental changes, relationship between radial growth and climate was studied using basic dendroclimatological methods. For this purpose, we developed firstly a 103-year long (1913-2016) radial increment chronology from 14 ash tress (25 radial increment series). The influence of climate on the growth of E. ash was evaluated by comparing radial indices with seasonalized (three-month period) and monthly temperature and precipitation data, using correlation analysis (seasonalized) and response functions (seasonalized and monthly). On the basis of correlation analysis it was found that low precipitation in spring (April-June) and early summer (May-July) as well as high temperature in spring, early summer, summer (June-August) and late summer (July-September) were among the most important factors limiting radial increments of E. ash. In contrast, response function analysis (seasonalized data) showed that only precipitation in early summer (May-July) had a significant effect on radial increment indices values and other three-month periods were not recognized as seasons with significant growth reductions. Further, we also performed response function analysis where predictors were principal components of a set of mean temperature and precipitation data only for months in ‘’significant’’ seasons by the correlation analysis. These results pointed out that there was a strong tendency towards positive response to June precipitation. A dendroclimatological study of European ash was performed for the first time in Serbia. Our findings are of preliminary character and in order to reveal main climate factors of importance in controlling annual growth variability of European ash in the studied area, future studies of E. ash radial growth-climate relations are necessary to be performed. Such studies of growth-climate are of special importance for here analyzed tree species having in mind in the recent years observed severe crown dieback that has led to great concern for the future of ash in many parts of Europe.

Key words:
radial growth, climate, dendroclimatology, European ash, Serbia

Thematic field:
Forest Menagement Planning

Date of abstract submission:
05.09.2017.

Conference:
Šumarska nauka u funkciji održivog razvoja šumarstva
25 godina šumarstva Republike Srpske