Distribution and abundance of plants has been correlated with a variety
of complex environmental gradients. Environmental factors affect plants
growth and need to be understood by ecosystem managers. This study was
carried out to examine the relationships between site factors and
different vascular and non-vascular plants in north of Iran. For this
purpose, vegetation and soil sampling was performed along 8 transects
each with a length of 300 m in key areas of the rangeland. Also,
topographic properties including elevation, slope and aspect were
recorded in sampling points, too. Using TWINSPAN, classification of the
vegetation was performed. After grouping of the species, Multivariate
technique of Principal Component Analysis (PCA) was used to analyze the
relationships between vegetation and site factors. The results of
classification revealed that species are classified to 6 ecological
groups. The interesting result was that vascular and non-vascular
plants were positioned in approximately separated groups. Also, each
group according to the contained species showed different correlation
with site factors. Properties of nutrient status, EC, texture and slope
aspect were the most important factors that correlated strongly with
the distribution of ecological groups in the study area, but the
strength and weakness of the correlation was different based on the
species of each group