Geographical distribution and estimation of the climatic tolerance ranges of Poa scaberula (Poaceae) in South America

Abstract

This paper analyzes the potential distribution of Poa scaberula (Poaceae) in South America. The study area includes the Andes and the Sierras Pampeanas of Central Argentina. Based on records of occurrence and environmental data, we modeled the potential distribution and identified the areas of high probability of presence, evaluating the contribution of climatic variables to the model, and estimating the ranges of climate tolerance. The species distribution models showed that P. scaberula has a suitable habitat of ca. 289,062 km2 in the study region. We identified annual minimum temperature as the critical factor shaping habitat suitability for P. scaberula. Moreover, the species shows a broad ecological tolerance, being able to withstand extreme conditions of low temperature ('11.8 ºC) and rainfall (<664.5 mm annual) related to elevational and latitudinal gradients; these gradients strongly contribute to the delimitation of the species distribution in South America.