Climate change drives the retreat of Aethionema spinosum (Brassicaceae) to high-elevation refugia

Global climate change poses an increasing threat to biodiversity, prompting scientists to utilize ecological and evolutionary knowledge to address this challenge. Understanding these fields and their interconnections is crucial for improving conservation strategies. Accordingly, we conducted a study to assess the potential repercussions of climate change on Aethionema spinosum, a plant species endemic to the mountains of the Irano-Turanian floristic region. Employing ecological niche modeling (ENM), we projected the potential geographic distribution of A. spinosum under current conditions and two future climate scenarios (SSP2-4.5 and SSP5-8.5) for the period 2041-2060. Key climatic factors, including annual mean temperature (bio1), isothermality (bio3), and precipitation of the wettest quarter (bio16), exhibited the highest percentage contribution rates influencing the distribution of A. spinosum. The current model predicted the distribution of A. spinosum in montane areas, while under future-climatic conditions, a reduction and shift toward higher elevations were anticipated. Notably, substantial losses were observed in areas proximate to existing habitats. These findings are useful for the management and conservation of A. spinosum and provide insights into the potential future impacts of climate change on its distribution in the Irano-Turanian region.