Distribution modeling of the genus Gammarus Fabricius, 1775 in Elborz and North and Central Zagros: An approach based on ensemble model

A variety of organisms are present in Freshwater ecosystems that the knowledge of species distribution is essential to understand the ecological and evolutionary factors that determine patterns of biodiversity. The construction of a species distribution model is an alternative approach for the study of its geographic range. Therefore, in this study, the distribution of freshwater amphipods of the genus Gammarus in Iran was investigated using SDMs distribution models. The ensemble modeling approach (eSDM), GAM, GLM, MARS and RF models were used. AUC and Kappa criteria were used to evaluate the mentioned models. Also, climatic variables, topography, vegetation and soil quality were used for modeling purposes. The results showed that single models predicted the suitable habitat for taxon (AUC=0.90). The increasing level in soil organic carbon (SOC) and Bio18 variables lead to an increase in habitat suitability. Also, they are mostly recorded at an altitude between 1000 to 2500 meters, but, the increase or decrease in height does not have a linear effect on the habitat desirability in this genus. Therefore, the predicted distribution for this genus indicates the combined role of soil biomass, vegetation and precipitation parameters that can determine the distribution range of the genus Gammarus in Iran.