RANGE SHIFT OF BROMUS TOMENTELLUS BOISS. AS A REACTION TO CLIMATE CHANGE IN CENTRAL ZAGROS, IRAN

Abstract

Climate change has been a serious matter in the last two decades and many studies focused on its different aspects. The question about the effect of a changing climate on organisms is valid for every single living soul. In this paper, we discussed the effect of climate change on geographical distribution of Bromus tomentellus Boiss. in Central Zagros, Iran. To do so, we used 19 bioclimatic variables and 8 modeling approaches (Generalized Linear Model (GLM), Surface Range Envelope (SRE), , Flexible Discriminant Analysis (FDA) Classification Tree Analysis (CTA), Artificial Neural Network (ANN), Generalized Boosting Method (GBM), Multivariate Adaptive Regression Splines (MARS) and Random Forest (RF)) to quantify the climate change in 2080 and scrutiny its effects on range shift of Bromus tomentellus. The results showed that annual precipitation (BIO12), mean temperature of wettest quarter (BIO8), mean diurnal range (BIO2) and temperature seasonality (BIO4) has the most importance for habitat suitability of this species. Bromus tomentellus will lose 65% of its climatically suitable habitats due to climate change in 2080, while 13.94% of current unsuitable habitats will become suitable. Thus, its habitat will shrink by 51%. Most of habitat loss will be in the plains and almost all of habitat gain, is on the highlands.