Intraspecific competition of Amygdalus orientalis as influenced by physiographic factors

The objective of this research was to study the intraspecific competition for Amygdalus orientalis as influenced by physiographic factors (Slope, Aspect and Elevation) in the Semiroms Tang Khoshk forest reserve. To this aim, a number of 30 circular plots each encompassing 0.2 ha were randomly recorded in the study area. Within each plot, four circular competition plots were designed, and the competition amongst shrubs were measured by means of Schütz competition index. The physiographic attributes including slope, aspect and altitude were recorded within each plot. Non-parametric tests as well as the analysis of variance were used to analyze the dataset. The results showed that the competition index is substantially higher on western slopes. In addition, the competition index decreased on elevations higher than 2201- 2300 m, as well along with increasing the slope. It can be concluded that the competition amongst shrubs for nutrient and resources at high altitudes and on steep slopes is intense due to low depth of soil and limited nutritional resources. Thus, this should be considered in the plantation and forest management in the high elevations and on steep slopes. Moreover, this should be followed by optimization of the distance between seedlings.