مقایسه ساختار اراضی مرتعی و میزان تخریب پیوستگی سیمای سرزمین در زیرحوزه‌های آبخیز ایریل، استان اردبیل

The aim of this research was to compare the rangelands structure and landscape degradation in Iril sub-watersheds, Ardabil province. Land use map and the Landscape Fragmentation Tool were used to determine 4 classes of patch, edge, perforated and core through 5, 10, 15 and 20m cell sizes. The landscape metrics of LPI, ED, cohesion, mesh, split, and AI were calculated using Fragstats software. Results showed that the low value cohesion and high values division metrics were in sub-watershed 5. Also, the LPI in 8 and 9 sub-watersheds were 89.30 and 84.12. The highest and lowest values of patch classes were attributed to 15×15m, and 5×5m cell size, respectively. The value of the edges, perforations and core does not change through different cell sizes. The inverse correlation between perforated index and cohesion (R2=-0.94) indicates a less-disturbed landscape in higher cohesion values. The positive correlation of split and perforated indices demonstrates a dis-connectivity and landscape fragmentation in high split index value. The landscape degradation are high in low patch and core area values and high edge amounts. High NP and more edge values indicate a reduction in landscape connectivity, while, the high values of core index specify the enhanced ecosystem connectivity.