ALTITUDINAL CHANGES IN THE WOOD ELEMENTS OF Pinus nigra IN TWO DIFFERENT ASPECTS OF MOUNTAIN ULUDAG,TURKEY

摘要

In this study, the anatomical characteristics of Pinus nigra JF Arnold(black pine)in Mountain Uludag were studiedusing the samples from six dif-ferent elevation zones on both northern and southern aspects. On the wood sections, radial and tangential diameters of tracheids, their frequencies, wall thick-nesses and lengths, ray numbers per mm, ray heights and widths were measured.It is obtained that the di-ameters and lengths of tracheid (tracheid wall thick-nesses， number per mm²） increased （decreased）along the mountain from lower to upper elevations, following by southern and northem aspects, respec-tively.Our results showed that the wood samples were classified into two main groups as lower(first group, 550-1150 m a.s.1) and upper (second group, 1350-1550 m a.s.1)elevations.Elevational differ-ences were found as the decisive factor forming the main groups, while the subgroups were clustered by aspect in particular.