Climate change impact on Olneya tesota A. Gray (Ironwood) distribution in Sonoran desert using MaxEnt Modeling approach

Based on different climatic scenarios, the distribution of the Olneya tesota A. Gray (Ironwood) has been modeled using MaxEnt modeling approach in the Sonora State of Mexico. Maximum Entropy species Distribution Modeling was used to predict distribution probability. 71,168 presence data and BIO1 to BIO19 variables of Worldclim BIOCLIM dataset for the present time, 2050 and 2070 used for modeling. The model performed with an acceptable range of sensitivity for training data (AUC=0.927) and random prediction (AUC=0.5). The results demonstrated that the high contributed variable on the presence of the O. tesota A. Gray is BIO17  Precipitation of Driest Quarter (48.3%) and the low contributed variable is BIO2=Mean Diurnal Range (Mean of monthly (max temp - min temp)) (0.9%). This means that the presence of the species is highly depended on dry months precipitation of which doesn’t have high fluctuations according to the used climate change scenario. Temperature fluctuations have not affected O. tesota A. Gray presence as it is known as a resistant species for extremely high temperatures. Therefore the probability of the presence of the species shows a significant increase on high altitudes mountains on the north-east of the Sonora state. Finally, the study concludes that the climate change will affect the distribution of the O. tesota A. Gray as an extinction risk and the same time will help the expansion of the species presence probability on the region. And it has been encountered new regions to recommend this valuable species as a reforestation alternative for conservation and management strategy like Soyopa, Aguaprieta and Sahuaripa municipalities among the others.

Keywords:

Ironwood , distribution , Climate change , Sonoran desert , Mexico