Distribution pattern of oak species (Quercus brantii) and its relationship with some soil factors (case study: in Khanmirza region, Chaharmahal va Bakhtiari)

Plants distribution patterns is one of the important characteristics of plant community, and it is so important for ecological explain and description of plant species as well as sampling methods. On the other hands, environmental variables are among of the main factors that effects on plant distribution and occurrence. Therefore, this study was done for determine distribution patterns of Quercus brantii and its relationship with environmental factors in Khanmirza region of Chaharmahal va Bakhtiari in 2012. Plants sampling carried out in four key-area and in each key-area ten 20*20 m2 plots across two transects. In addition, in each plots, one soil sample was taken. Distribution patterns was determined by distance (Zimer-Johnson index, Eberhart index, Hopkines index, T Square index, Hines and Holgate index) and quadratic (variance /mean index, Green index, Lioyd index, Morisita index, and Standard Morisita index) indices. Linear regression and stepwise regression was used for determine of oak cover and environmental factors. The results showed that distribution patterns of Quercus brantii was followed as Aggregated. The results of relationship between oak cover and soil factors showed that oak cover had a positive relation with clay percent, pH, organic matter, total nitrogen and potassium as well as negative relation with stone percent. In addition, the most relation between oak cover and environmental factors was for organic matter (R2=44). It can be concluded that environmental factors (i.e. soil factors) had a critical role in oak forest and for suitable management attention to those relation is so important.