Determining the Spatial Distribution of Pistacia Atlantica Trees in the Closed and Grazed Areas Using Distance Indicators and Quadrate (Bagh-e Shadi Protected Area of Yazd)

In this study, an inventory with fixed area plots has been used. A total of 76 circular plots in the closed and grazed area were harvested and the species within each plot, the large and small crown diameters, the distance of the plot center to the nearest tree, the distance of the nearest tree to the first nearest neighbor, and the distance of the first nearest neighbor to the second nearest neighbor distance were also measured and recorded. Using the obtaineddata, the indices of dispersion patterns (Johnson zimmer, Eberhardt, Hopkins, Hines, Pielou, and C index) were calculated. Furthermore, the number of plants in each plot was measured and, using this information, the quadrate indices (green, morisita, dispersion index, and lioyd Index of Patchiness) were calculated. The results indicated that Johnson zimmer, Hines and Eberhardt dispersion indicators estimated the distribution pattern of the trees in the closed and grazed areas as bulked. The Hopkins index indicated the distribution of (Pistacia atlantica) trees in these two areas as random, while the C index revealed a uniform distribution pattern of trees in both areas. However, the dispersion pattern of the trees in the closed and grazed areas were respectively bulk and uniform according to the Pielou index. The quadrate indicators (Mvrysta, Dispersion index, and Lioyd Index of Patchiness) estimated the distribution pattern in both regions as bulk except for the Green index which indicated a random pattern for both areas. The results confirm the bulk distribution pattern for pistachia trees in the closed and grazed regions.