Modeling the effect of climate change on the distribution of plant communities in Zayandeh-Rud basin, Iran

Abstract

Climate change is one of the major threats facing various regions in the world, including the Zayandeh-Rud basin in Iran. Although numerous studies have been carried out to predict the effects of climate change on the distribution of plant species, one important issue that has been largely neglected is the examination of the impacts of climate change on plant communities. Therefore, in this study, we modeled the potential effects of climate change on the distribution of the existing plant communities in the study area, including Semi Steppe-Shrub, Semi Steppe-Semi Shrub, Semi Steppe-Perennial Herbaceous, Steppe-Semi Shrub, Alpine Vegetation, Semi Desert-Salty Plants, and Semi Desert-Shrub. Using the presence points of plant communities and environmental variables, we performed modeling of the current (1970–2000) and future (2070) distribution of the plant communities in the study area. The results of the MaxEnt modeling under two General Circulation Models (MRI-ESM2-0 and HadGEM3-GC31-LL) with SSP245 and SSP585 scenarios showed that the suitable habitats of many of the studied plant communities will face a significant decrease in the next 50 years. The most significant reduction in suitable habitat is projected for the Semi Steppe-Perennial Herbaceous community (18–29.4%) and the Semi Desert-Shrub community (19–29%) within the Zayandeh-Rud basin, highlighting substantial habitat contraction under future climate scenarios. These changes can have significant implications for ecosystem functions and the livelihoods of local communities. The findings of this study emphasize the necessity of designing and implementing targeted conservation and management programs for the plant communities in this important region in response to the growing threat of climate change. Therefore, our findings can guide managers in prioritizing plant communities and adopting proactive measures to mitigate the negative impacts of climate change.