Spatial pattern of Anagyris foetida L. shrubs in the Zagros forests

The aim of this study was to determine the spatial pattern and intra-specific interactions of Anagyris foetida shrubs in its unique habitat in the Zagros forests. For this purpose, 1-ha sample plot which is covered by relatively pure Anagyris foetida was established. The spatial location of each individual was calculated using azimuth and distance measurement. Furthermore, the biometric characteristics of the individuals were measured. Then, the spatial pattern of the shrubs were determined using the nearest-neighbor and pair correlation functions. In addition, the spatial correlation of shrubs size was determined using Mark correlation and Mark variogram functions. The measurement of biometric characteristics of shrubs showed that the mean collar diameter, height, crown area and number of sprouts were 5.15cm, 2.36m, 5.6m2 and 12.59, respectively. The density was 231 shrubs per hectare. Based on the results of the spatial pattern analysis, the shrubs were aggregated at small spatial scales and tend to follow random distribution pattern at larger distances although the results of the pair correlation function (g) showed an aggregation at distances 13-17m. The results of the Mark correlation and Mark variogram functions showed no spatial correlation among shrubs for the biometrics characteristics implying that the shrubs arrangement by their size follows complete randomness. It was concluded that although there is a positive interaction (aggregation) in small spatial scales, no specific spatial structure was observed. The size of the shrubs was not spatially correlated and the neighboring shrubs were randomly distributed with different sizes.