QUANTITATIVE CHARACTERISTICS OF COLISEUM MAPLE (ACER CAPPADOCICUM GLED. 1785) IN RELATION TO PHYSIOGRAPHIC FACTORS IN HYRCANIAN FORESTS OF IRAN (CASE STUDY: SANGDEH, MAZANDARAN PROVINCE)

The aim of this study was to investigate the effects of physiographic factors (altitude, slope and direction gradients) on quantitative characteristics of coliseum maple (Acer cappadocicum Gled. 1785) trees in Sangdeh, Mazandaran province. For this purpose, 93 sample plots of 0.1-hectare area each were laid out with a selective sampling method in different physiographic conditions, on the parts where the frequency of this species was high. Quantitative characteristics of coliseum maple trees in plots were recorded. To evaluate the group response of quantitative characteristics of coliseum maple trees to physiographic factors the multivariate analysis (RDA) was applied using Canoco Version 4.5. Results showed that the effects of physiographic factors on the quantitative characteristics of coliseum maple trees were significant. The correlation results demonstrated that with the increased of altitude, the characteristics as collar diameter, diameter at breast height, diameter at onset crown, total height, trunk length, trunk length to first branch, mean of crown diameter and crown length of coliseum maple trees, were significantly reduced. The highest values of diameter at breast height, collar diameter, diameter at onset crown, total height, and trunk length of maple were observed in the northwest aspect. The redundancy analysis (RDA) results showed that the quantitative characteristics of coliseum maple trees were located in the negative direction of the first axis and altitude had an inverse correlation with quantitative characteristics.