نوع مقاله : مقاله پژوهشی
موضوعات
عنوان مقاله English
نویسندگان English
Background and Objective: Landscape metrics are usually the broadest and most diverse measure of spatial scale. Disturbance in environments is an undeniable problem, transforming the landscape into a mosaic of diverse habitat patches.
Method:In order to prepare land cover maps and analyze changes, satellite images TM(1988), ETM+(2001) and OLI(1400) were used, respectively, as well as metrics of class area, patch number index, mean patch size, patch density and patch edge density, and mean shape index. The results of the study of landscape change in the Mehran region show that during the first period (1988-2001), the area of forested land in the region decreased by (11446 hectares), while agricultural land increased (1575 hectares). The decrease in the area of forest cover and the increasing trend of agricultural land use indicate the replacement and conversion of the natural cover of the region (mainly "fair rangeland") with agricultural lands. On the other hand, the area of fair rangeland (16974 hectares) has decreased (in both periods) and poor range lands have increased, which indicates the trend of degradation in the study area (in both periods). The decrease in the area of forest cover and fair rangelands in the region and the increasing trend of poor rangeland, agriculture, and barrenland use indicate overall degradation in the region and the replacement of weaker land uses in the region. In addition, in both time periods, the amount of residential and barrenland has had an upward trend, indicating an increase in population and also an increase in human pressure in the study area.
Discussion and Conclusion: The results also showed that the increase in the number of patch and the decrease in the average area were two important indicators of degradation, and the trend of degradation and degradation of the landscape was increasing.
کلیدواژهها English