DSPATIAL STAND STRUCTURE ANALYSIS OF ULUDAG FIR FORESTS IN THE NORTHWEST OF TURKEY

Abstract

Forest structural characteristics, which are one of the key determinants of species and habitat diversity, have also been used as a constitutive factor in sustainable forest management. This study aimed to analyse the spatial structure (Clark-Evans, segregation and species mingling) of pure fir (7 plots, 1000-1600 m a.s.l.), fir dominated (5 plots, 1000-1400 m a.s.l.) and fir-beech co-dominated (7 plots, 1000-1300 m a.s.l.) stands at the center and edge distribution of Abies nordmanniana ssp. bornmuelleriana in Sub-euxine zone of Euro-Siberian region of Turkey. The Shannon diversity of tree species was found significantly (P < 0.01) lower in the edge distribution (Bolu-Aladag) (0.418 +/- 0.081) compared to Yenice (0.824 +/- 066). Fagus orientalis showed a clumped distribution in fir dominated stands where it is not competitive compared to Abies nordmanniana ssp. bornmuelleriana but it had a spatial association with other species in co-dominated stands Light demanding deciduous trees such as Quercus hartwissiana, Carpinus betulus and Populus tremula were observed in pure groups, whereas Pinus sylvestris and Pinus nigra did not show a tendency towards clumping and had a spatial association with other species since they were located in upper stand layer. As shown in this study, spatial data in stand profiles provide new opportunities for understanding ecosystem structure and silvicultural treatments.