The influence of climate change on the suitable habitats of Allium species endemic to Iran.

Identifying the consequences of global warming on the potential distribution of plant taxa with high species diversity or a high proportion of endemic species is one of the critical steps in conservation biology. Here, present and future spatial distribution patterns of 20 Allium endemic species were predicted in Iran. In this regard, the maximum entropy model (MaxEnt) and seven environmental factors were applied. In addition, optimistic (RCP2.6) and pessimistic (RCP8.5) scenarios of 2050 and 2080 were also considered to predict the future spatial distributions. The results showed that annual mean temperature (BIO1), temperature annual range (P5-P6) (BIO7), soil organic carbon content, annual precipitation (BIO12), and depth of soil were the most important environmental variables affecting the distributions of the studied taxa. In total, the model predictions under the future scenarios represented that the suitable habitats for all Allium species endemic to Zagros except for A. saralicum and A. esfahanicum are most probably increased. In contrast, the suitable habitats for all species in Azerbaijan Plateau, Kopet Dagh-Khorassan region, and Alborz except for A. derderianum are most likely decreased under the future climate conditions. The present study indicates that the habitats of Alborz, Azarbaijan, and Kopet Dagh-Khorassan will be probably very fragile and vulnerable to climate change and most species will respond strongly negatively under applied scenarios, while Zagros species occupy new habitats by expanding their distributions. Therefore, determining conservation strategies for the species in these regions seems to be very important and high priority for decision makers.