Effects of Physiographic factors and Some Physical and Chemical Soil Properties on Distribution Amygdalus scoparia Spach. in 4 Areas of Markazi Province

Investigation on site demands of forest species such as physiographical factors and soil characteristic are necessary for improvement, reclamation and conservation of plant cover. Amygdalus scoparia Spach. is one of the most important forest species in Markazi Province with edible use, industrial, environmental and protective values. In this research, firstly, all of the regions were surveyed and with regard to variables such as aspect, altitude and slope, sampling performed by 61 plots and GPS device in four areas of Jalayer Saveh, Nimvar Mahalat, Jaftan Tafresh and Sarabadn Tafresh. In each sample plot, some physical and chemical soil properties (K, Caco₃, C, N, clay, silt, sand, EC, pH and P) and as well as quantitative measurement of species growth such as (tree density in hectare, crown diameter, height, basal area each tree, basal area in hectare and regeneration) were conducted and then the data were analyzed using SPSS and PC-ORD. The results of One Way ANOVA showed that of altitude, slope, Caco₃, EC, P in Nimvar Mahalat, sand and basal area in hectare in Jalayer Saveh and Sarabadan Tafresh, tree density in hectare in Sarabadan Tafresh had the highest amount. The lowest altitude and silt is in Jalayer Saveh. The results Principal Component Analysis (PCA) showed that all of the quantitative measurements of species growth were distributed in the positive direction of the 1^st axis. The highest positive correlation with the 1^st axis is in Jalayer Saveh and 2^nd axis in Nimvar Mahalat. Sand and N in the first quarter (Sarabadan Tafresh and Jalayer Saveh), altitude, slope and P in the second quarter (Nimvar Mahalat) and C in the fourth quarter (Jaftan Tafresh) are the most important affecting factors on distribution of Almond.