Modeling Stipa arabica Trin and Rupr. Habitat Displacement in Central Iran Using Ecological and Climate-Based Approaches

One of the main concerns of rangeland managers is to understand the factors that cause climate change and the effects of these factors on the main factors of rangeland management such as vegetation. Climate change in the rangelands of the highlands causes a decrease in biodiversity and deterioration in the downstream areas. This study aimed to predict the future habitat displacement of Stipa arabica Trin and Rupr. in the rangelands of Isfahan, Yazd, Semnan, and Kerman provinces, Iran under climate change conditions. The research objectives include identifying key environmental factors influencing Stipa arabica distribution, modeling its habitat suitability, and assessing potential shifts in elevation due to climate change. A predictive habitat map was developed by employing a logistic regression based on environmental variables, species presence/absence data, and geographic information system (GIS) analysis. To achieve this, key species associated with Stipa arabica were identified through expert interviews, and then, habitat characteristics were analyzed based on species behavior. Data on vegetation cover and environmental factors were collected from the station established by 2020, and habitat suitability was modeled in ArcGIS 10.3. The Kappa coefficient was used to assess model accuracy. The Kappa coefficient was 86, which according to the classification by Koch and Smith, falls into the category of models with good accuracy. The results indicate that Stipa arabica currently occupies elevations between 1,600 and 2,550 m above sea level, with a 75–100% probability of occurrence across approximately 5.2 million ha (10.7% of the study area). However, climate projections suggest that by 2050, its suitable habitat will shift to higher elevations 1,750–2,800 m under scenario (RCP 4.5) and 1,850–3,050 m under scenario (RCP 8.5). As temperatures rise due to climate change, the total suitable habitat area for Stipa arabica is expected to decline, forcing its migration to cooler, higher-altitude regions. To mitigate the impact of climate change on Stipa arabica, it is recommended that conservation efforts focus on the protection of higher-altitude habitats and the establishment of ecological corridors to facilitate species migration. Additionally, future research should explore adaptive management strategies for maintaining rangeland biodiversity in response to ongoing climate change.