Relationship between vegetation and environmental factors in the Anatolian oak (Quercus petraea L. subsp. iberica (Stev.) Krassiln) habitat: a case study of Asalem forests, Guilan

This study was carried out to investigate the relationship between vegetation and environmental factors of Quercus petraea habitat in the district No. 8 of Asalem forests، Guilan. Data were selectively collected in 30 sampling plots of 50 m × 50 m. In each plot، diameter at breast height (dbh) of trees ≥ 10 cm were measured considering the tree species. Herbaceous species data were taken using Whittaker’s nested plot sampling، the species coverage were estimated using Domin criterion، and types of the species were identified in each plot. In addition، the most important topographical factors were recorded in each plot. Soil samples were taken from depths 0 to 20 cm in each plot center and to characterize ecological species groups، TIWNSPAN method was used. Also، Canonical Correspondence Analysis (CCA) was applied to study relationship between environmental factors and vegetation composition on plot level. Results indicated that there are four ecological groups in the studied area; and that elevation، aspect، bulk density، gravel percent، organic carbon، organic matter and total nitrogen were the most important factors in determining the ecological groups.