Modeling the Distribution of Species Pistacia atlantica in Ilam Province using MaxEnt Methods

Determining the distribution status of species and habitats under their occupation is very important in species conservation and management programs, but the available time and budget make large-scale species studies difficult and in many cases impossible. Therefore, in this field, species distribution modeling methods are used. Modeling the distribution of plant species with the aim of identifying areas prone to conservation conservation and afforestation is important. The aim of this study was to model the distribution of pistachio species using methods and feasibility study of the development of this species in Ilam province.

For this purpose, the presence points of the species throughout the province were collected using stratified random sampling method and their geographical coordinates were entered into the software MaxEnt. Map of environmental factors including 19 climatic variables, 3 topographic variables and snow cover variables were prepared. These variables were used as model input and the relationship between attendance data and environmental variable maps was defined mathematically using software. Then species distribution prediction maps were prepared using Maximum Entropy (MaxEnt) modeling method.

The results of model evaluation showed that the model with the area under the plot curve AUC: 0.947 has an excellent prediction versus 0.5 which means that the prediction is random. Jack Knife test also showed that the model was successful in predicting the distribution of pistachio species and the factors of annual temperature range, mean temperature ‌, isotherm index, annual precipitation and altitude, respectively, had the greatest impact on the presence of this species in Ilam province.

The results of this study have provided key and important information about the tolerance range of Pistica species to environmental variables. This information is effective in making management decisions to prioritize conservation areas and to take remedial and conservation measures, especially in areas where vegetation is being degraded, and increases the chances of success in planting and rehabilitation projects.