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Potential habitat modeling of endemic species is an appropriate method to maintain biodiversity, ecosystem function and rehabilitation of rangeland ecosystems. Astragalus caragana, A. cyclophyllon and A. podolobus are endemic in Iran's rangelands and some neighboring countries. The three native species could endure environmental stresses due to their distinctive ecophysiological characteristics. They play important roles in sustainable pastures production, recreation and improvement. They suffer severe threat from many factors including; grazing, agriculture and invasive exotic species. We analyzed the potential habitat of three native plant species in central Iran basing on the grid map with the resolution of 1-km. We used inventory records from field surveys, herbarium collections and 22 environmental factors to explore the environmental influences on given species distribution by Maximum entropy (Maxent) model. Maxent is a species distribution model that uses species occurrence and environmental data for predicting potential species. The results of our study indicated species occurrence has strong correlation with environmental factors such as mean temperature of wettest season, elevation and precipitation of coldest season. We evaluated the model accuracy by AUC (area under the receiver operating characteristic curve) based on an independent test data set. AUC values indicated the high power of Maxent to create potential habitat map (AUC A. caragana =0.988, AUC A. cyclophyllon =0.927, AUC A. podolobus =0.923). It is important to consider that AUC values tend to be lower for species that have broad distribution scope, such as A. podolobus distribution. Most suitable potential habitat distributions of the three species were predicted in the western and southwestern parts of rangelands in Isfahan province. Visual comparisons of the actual distribution map of the three species with produced Maxent maps represent a good agreement. In general, the model demonstrated that the occurrence of the given species is highly probable when the elevation is between 2,200 and 3,000 m and mean temperature of wettest season less than 3°C. This model, therefore, can be applied to recognize potential sites for rangeland reclamation projects.

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Aim Central part of Iran harbours populations of wild ungulates that are threatened or extinct over large parts of the region, and are likely to be impacted by climate change. In this study, we predicted the impact of climate change on the distribution of three vulnerable ungulates in central Iran. We then evaluated future suitability of corridors connecting the protected areas for movement of the ungulates in response to climate change. Location Central Iran. Methods Impact of climate change on distribution of goitered gazelle (Gazella subgutturosa), wild sheep (Ovis spp) and wild goat (Capra aegagrus) was predicted adapting an ensemble modelling approach and under the RCP 8.5 emission scenario. We then used CIRCUITSCAPE software with current and future distribution maps to identify corridors for movement of the three ungulates, and evaluate likely changes in their suitability under climate change. Results Our results revealed that climate change might result in loss of 55%, 69% and 76% of suitable habitats for goitered gazelle, wild sheep and wild goat by 2070, respectively. These losses also resulted in some protected areas to become unsuitable for the ungulates. However, we identified key protected areas with the potential for future protection of these ungulates. For the three species, we also identified corridors which would persist into the future, allowing the impacted populations to move in response to climate change. Main conclusions Conservation of ungulate populations in Iran mainly depends on the protected areas. To maintain the role of the protected areas in conserving these mammals under climate change, we recommend the incorporation of their potential future distribution into conservation plans, increasing protection status of the key protected areas, and maintain critical corridors. In this regard, combining results of distribution and connectivity models provides useful information for effective management of these ungulates in the future.

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In recent years, global climate change has had significant biological, temporal, and spatial effects on many terrestrial habitats. The objective of this study was to evaluate the effect of climate change on the geographic distribution of Juniperus excelsa and prioritize its habitats for protection against these effects until 2070. The study was conducted using the MaxEnt species distribution model and two data series GFDL-CM3 and MRI-CGCM3 under scenarios RCP2.6 and RCP4.5 of the 5 th IPCC report. Our results revealed that elevation, minimum temperature of coldest month, precipitation of coldest quarter, annual mean temperature, and slope aspect, in that order, have the greatest effects on the species' distribution in the study area. Under optimistic scenario RCP2.6, both models predicted that the species' presence area will grow, but under RCP4.5, models predicted that by 2070, some parts of its habitat in western and central heights will be lost because of change in climate parameters like minimum temperature of coldest month and precipitation of coldest quarter. Under the latter scenario, the northeastern parts of the study area showed no changes in terms of climatic parameters and climatic niche. The results of both climate data series indicated that the Juniperus excelsa will slowly migrate to higher elevations to cope with the changing climate. Assessment of the results through field studies showed that outputs of GFDL-CM3 are closer to the reality. Citation: Fatemi SS, Rahimi M, Tarkesh M, Ravanbakhsh H (2018). Predicting the impacts of climate change on the distribution of Juniperus excelsa M. Bieb. in the central and eastern Alborz Mountains, Iran. iForest 11: