Climate Change Impacts on the Distribution of oriental beech (Fagus orientalis Lipski) in the Hyrcanian Forests of Iran

Due to global climate change, climate change in Iran is inevitable and the results of the climate studies clearly show that the Hyrcanian climate has been warmer over the past 50 years. In this research, the current and future distribution of oriental beech (Fagus orientalis Lipsky) was studied using an ensemble method including five different species distribution models. We used five general circulation models under four existing reprehensive concentration pathway (RCPs) to project the impact of climate change on the distribution of oriental beech by 2070. Also, the stable, gained and lost suitable habitat of oriental beech were determined using range size change analyses under climate change. The results showed that the area of suitable habitats with high certainty would be decreased by 72.79% and 89.88% under RCP 2.6 and RCP 8.5, respectively, by 2070. The results of the range size analyses of oriental beech showed only 24.84% of suitable habitat would remain in the most optimistic condition (RCP 2.6) and stable the suitable habitat would decrease by 7.13% under RCP 8.5 by 2070. Also the lowest and highest rate of suitable habitats lost will be by 72.79% and 89.85% under RCP2.6 and RCP 8.5, respectively, by 2070. It is suggested that the climate change impacts should be considered in the management decisions and conservation plans related to the oriental beech in the Hyrcanian forests