Using Wood Anatomical Proxies to Study the Effect of Climate on Black Alder (Case Study: Forest Park of Astara)

Although in the recent years, the effect of ground water level on radial growth of black alder has attacked attentions of scientist but to comprehensively interpret the results of such studies, we need to investigate the independent influence of climate on ring width and other wood anatomical features of this species. Hence, in current study, the influence of climatic factors on the annual ring width and some vessel features of black alder were investigated in a Forest Park located in Astara (northeast of Iran). In this site, 11 trees were selected and after preparations, cross sections were scanned from two or three pith-to-bark strips of each tree. After distinguishing the growth rings, tree ring width and some quantitative vessel features were measured in the last 20 growth rings of each tree using an image analyzing software and their relations with different climatic factors were studied in the monthly, seasonally and yearly scales. Results indicated that in long term scales, only average vessel lumen area show a statistically meaningful correlation with meteorological parameters. In this site, rainfall increased the vessel size while evaporation rate had a negative effect on this feature. Since there was no age trend in vessel related chronologies and the greater strength and number of found correlations with monthly climate, these features can be suggested to be used in dendroclimatological studies using this species.