Modeling The Distribution of Tamarix ramosissima Ledeb. In Isfahan Province Based on Maximum Entropy Model (MAXENT)

Tamarix ramosissima, due to its high potential for settling in arid and semi-arid lands, considered as one of the valuable plants for creating vegetation in these areas. The use of the plant in the east of Isfahan can be reproduced and expanded for desertification purposes; however, information on its habitat and ecological requirements is limited. The aim of this study was to identify the factors affecting the distribution of this species and to model the potential habitats for the growth of this species in Isfahan province. The distribution points of the plant were determined according to the flora of Iran and by referring to the region, sampling was performed and its geographical and ecological characteristics were recorded. A total of 55 distribution locations were registered in 14 cities. Using the maximum entropy model, 19 bioclimatic and three topographic variables were used to model the distribution of the species and the importance of each of them in the modeling process was evaluated by Jack Knife test. The results showed the area under the receiving operator curve was equal to 0.967 by using Maxent model. The produced model had an acceptable accuracy as its Kappa coefficient index was 0.80. .Environmental factors related to topography including slope percentage and climatic factors precipitation of coldest quarter, annual precipitation, temperature annual range and mean temperature of coldest quarter had the greatest impact on species distribution, respectively. According to the prediction of the presence of the species based on habitat potential, about 19% of the area of ​​Isfahan province, provided the absence of limiting factors, has the desired potential for the presence of this species.