Determination and Analysis of Ecological Species Groups with Respect to Environmental Factors, (Case study: Kheiroudkenar Forests)

This study was done in oriental beech (Fagus orientalis) communities of Namkhaneh, Gorazbon and Chelir districts in Kheiroudkenar-Noshahr forests. The aim of the research was investigation on classifying the vegetation, recognition of ecological species groups and comparing different environmental conditions among them.
Selective stratification sampling method was used to locate samples. One plot is sampled on each aspect in each community. Totally, 120 samples were selected in beech communities in the study area. The plot size was 400 m2 considering to Minimal area method. At each sample, floristic list and an estimate of percent cover and abundance of each vascular plant in separate strata were recorded with using of Braun-Blanquet scale. At the center of samples, two soil samples were taken from 0-10 and10-30 cm layers of mineral soil. The physical and chemical soil properties in each sample were analyzed. Cluster analysis was used to classification of samples. Multi-response Permutation Procedures (MRPP) was used to test the hypothesis of no difference between groups in species space and also in environmental variables space. Tukey test was used to compare the environmental variables means among groups.
The results showed that the distribution of ecological associated with Aspect, Clay, Total nitrogen, Organic matter, Phosphorous and exchangeable cations. There is no direct relationship between distribution of ecological groups and Elevation, slope, percentage of sand and silt, C/N ratio, pH, bulk density and porosity in the study area.