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BIODIVERSITY OF WOODY SPECIES IN Acer platanoides SITES IN THE SHAFAROUD FORESTS, GILAN (IRAN)

In this research, biodiversity was investigated in the species diversity level. The objective of this research was to study of Norway Maple (Acer platanoides L.) dispersion and biodiversity of associated woody species in the Shafaroud forests, Gilan (IRAN). In this regard, a 0.5 ha lozenge sample plot was selected with considering presence of Norway Maple in each site. In each plot, geographic characteristics (i.e. slope, aspect and elevation) were documented, then diameter of breast height (dbh) of trees >10 cm were measured. Afterwards, within 0.5 ha plot three 100 m2 circular subplots were established for recording of saplings in diameter class 2-10 cm and 50 m2 circular subplot was located within each 100m2 subplot, for recording of seedlings in diameter class 2> . In addition, type of woody species identified and documented. Shannon-Wienerʹs and Simpsonʹs diversity indices were used for evaluating of woody species diversity, and also evenness and richness indices were calculated. Results showed that Shannon-Wienerʹs index in seedling layer had the highest value and in the tree layer had the least value. Simpsonʹs index in trees layer had the highest value and in the sapling layer had the least value. For detecting relationships between diversity indices with richness and evenness, the most correlation of Simpsonʹs index was shown with its evenness and the least correlation was with richness in the tree layer, whereas in the sapling and seedling layers the most correlation of Shannon-Wienerʹs index was with richness and the least of that was with its evenness. Also, the most population of Norway Maple was found in slopes > 50 percent, northern aspect and in altitudes from 1000 to 1200 m and the lowest value was in slopes < 50 percent, eastern aspect and in altitudes from 400 to 800 m a.s.l.