Journal of Rangeland

Applying appropriate sampling methods ensure the efficiency and accuracy of from inventory and monitoring results in rangelands. Vegetation type, spatial vegetation pattern and plant size affect selection of proper plot shape and size in vegetation measurements. It enhances the measurements accuracy and reduces observed variance among measured samples and save sampling time. This study aimed to determine proper plot size and shape for vegetation study in semi-steppe rangelands dominated by Bromus tomentellus- Astragalus verus in Isfahan province. Square, rectangular and circle plots with size of one and two square meters were compared in measuring vegetation cover in a dominated random vegetation pattern. A systematic random sampling method was used and variance analysis of measured attributes was conducted. According to the results, there were significant differences between various plot sizes (P< 0.01) but plot shapes didn't differ significantly. Evaluating variation coefficient of vegetation cover in plots with different size revealed that 2 m² plot was more efficient and accurate than 1 m² plot size. Rectangular plots in vegetation cover measurements produced data with lower coefficient of variant than other plot shapes. Overall, 2 m² rectangular plots is suggested as an appropriate plot size and shapes in vegetation cover measurements of rangeland with similar vegetation patterns in semi-arid rangelands.