Floristic Structure and Vegetation Composition of Boralan Mountainous Rangelands in North-Western Azerbaijan, Iran

Document Type: Research and Full Length Article

Authors

1 Range Sciences, Gorgan University of Agricultural Sciences and Natural Resources

2 Urmia University,

3 Gorgan University of Agricultural Sciences and Natural Resources

Abstract

Recognition of habitats and conditions of species presences in different
situations can be effective in proper utilization of vegetation. Little is known about the
vegetation composition of Boralan Mountain region located in North West of Iran in the
border of Turkey and Azerbaijan with the altitude range of 800-2000m. The aim of this
study therefore was to investigate the floristic composition quantitatively and analyze the
vegetation response to altitudinal gradient conditions of mountain. Firstly, plants were
collected by floristic field survey and identified using the floras. To investigate the
relationship between the gradients of elevation and vegetation, two transects of 100m were
established at every 100m of elevation belts and the percentages of canopy cover and
density of species were totally recorded in 20 plot samples using a random plot design.
Plant community zones were characterized on the basis of species’ cover dominances using
cluster analyses. According to this study, the area includes 108 species that were classified
into 26 families. Totally, Poeaseae and Asteraceae with 40 percent cover dominance were
more frequent than other families. Based on species similarity of elevation classes, the
cluster analysis led to four vegetation type groups. The grass group and the shrub group
occurred on high altitudes at 1900 m and lowland sites at 800-1300 m, respectively. The
results also showed that elevation variations had considerable effects on diversity and
richness indices of vegetation groups with the highest number of species at high altitudinal
belt. It seems that precipitation improvement and low grazing intensities has mainly caused
these changes.

Keywords