Potential habitat modeling of Astragalus verus Olivier using Ecological- Niche Factor Analysis

This study aimed to generate potential distribution map of Astragalus verus Olivier, in Fereydounshahr rangelands in Isfahan province with 1000 square kilometers area approximately. Potential distribution map of the species in the study area was produced using Ecological Niche Factor Analysis (ENFA) methods, applying presence data of the species and some environmental variable maps (topography, climate and soil maps). Vegetation types dominated by A. verus was checked in the study area and 50 sites with presence of the species were recorded using a stratified- random sampling approach. Soil maps were obtained from seventy soil profiles and climatic maps were produced using data from 10 climatic stations. 9 maps of different soil properties, 19 maps of various climatic parameters and 3 maps of different topoghraphic variables (from a 90 by 90 meters DEM) were generated using geostatistic method.. These maps were used as input layers for ENFA model. Results showed that soil EC, caco3 and organic carbon content, and pH together with slope percentage and monthly mean temperature were respectively the most important environmental factors influencing the species ecological niche. The produced species distribution model showed high accuracy (calculated Kappa coefficient, ROC area under curve plots and cross validation were 0.69, 0.85 and 95 %, respectively. given that industrial and medicinal value of A. verus, the produced potential map can be used for conservation and habitat improvement programs of the species.