Izvorni znanstveni članak
https://doi.org/10.15177/seefor.15-05
Growth-Climate Response of Young Turkey Oak (Quercus cerris L.) Coppice Forest Stands along Longitudinal Gradient in Albania
Merita Stafasani
; Agricultural University of Tirana, Faculty of Forestry Sciences, Koder Kamez, AL-1029 Tirana, Albania
Elvin Toromani
; Agricultural University of Tirana, Faculty of Forestry Sciences, Koder Kamez, AL-1029 Tirana, Albania
Sažetak
Background and Purpose: Turkey oak (Quercus cerris L.) is the most widespread species in Albania and less investigated from dendroclimatological point of view. Previous studies have reported that Q. cerris is sensitive to the environment when growing at different latitudes and ecological conditions. Based on this fact we have explored the response of different Q. cerris populations located along the longitudinal gradient.
Materials and Methods: The stem discs were sampled from six sites (Kukes, Diber, Rreshen, Ulez, Elbasan, Belsh) along longitudinal gradient ranging from north-east to central Albania. All oak forests stands grow under the influence of specific local Mediterranean climate. Tree-ring widths were measured to the nearest 0.001 mm using a linear table, LINTAB and the TSAP-Win program. Following the standard dendrochronological procedures residual tree-ring width chronologies were built for each site. Statistical parameters commonly used in dendrochronology were calculated for each site chronology. Relations between the tree-ring chronologies were explored using Hierarchical Factor Classification (HFC) and Principal Component Analysis (PCA), while the radial growth-climate relationship was analyzed through correlation analysis using a 19-month window from April in the year prior to tree-ring formation (year t - 1) until October in the year of growth (year t).
Results and Conclusions: The length of the site chronologies ranged from 16 to 36 years, with the Elbasan site chronology being the longest and the Belsh site chronology the shortest one. Trees at lower elevation were younger than trees at higher elevation. Statistical parameters (mean sensitivity (MS) and auto correlation (AC)) of site chronologies were different among them and lower values of AC1 showed a weaker dependence of radial growth from climatic conditions of the previous growing year. Principal component analysis showed that Belsh, Rreshen and Elbasan site chronologies were clustered in the first principal component accounted 36.6% of the total variance. The HFC indicated grouping of the site chronologies in two clusters, where Belsh, Rreshen and Elbasan site chronologies were grouped in the first cluster while Kukes, Diber and Ulez in the second one, confirming the results previously provided from PCA. The dendroclimatological analyses showed that the positive moisture balance in current April and previous September was the dominant climatic factor favoring the radial growth of Q. cerris in Albania.
Ključne riječi
endroclimatology; principal component analysis; hierarchical cluster analysis; correlation analysis
Hrčak ID:
139159
URI
Datum izdavanja:
19.5.2015.
Posjeta: 1.274 *