فهرست نشریات علمی دسترسی آزاد ایران

The purpose of this study was to classify ecological groups and their gradient analysis according to soil physio-chemical properties in the forest reserve park of SiSangan under the Buxus hyrcana Pojark. For this purpose, 46 systematic sample plots of 400 m2 (20×20 m) were selected. In each sample plot, canopy cover values by species abundance-dominance coefficients based on Brown-Blanquet's method were measured and then soil samples were taken in the both depth of 0-15 and 15-30 cm to analyze some properties such as OC, N, P, K, C/N, pH and EC, texture, lime and moisture content. Using TWINSPAN analysis of species cover percentages, three ecological groups determined in the area and using methods of Detrended Correspondence Analysis (DCA) and Canonical Correspondence Analysis (CCA) were used to explain relationships between ecological groups and soil properties. The results showed that the shape of the ecological groups in the area and soil factors including: silt and clay, organic carbon, nitrogen and C/N in the first depth, moisture content and available phosphorus in non-Buxus type and percentage of sand, acidity, electrical conductivity, lime, available potassium, organic carbon, total nitrogen and C/N in second depth in Buxus type were relatively correlated to each other. The results of ecological groups' classification into species-environmrntal factors and releve-environmental CCA biplot showed that sample plots and indicator species of each unit from each other in ordination diagrams were separated.