Potential distribution and influence of climatic change on Baccharis conferta Kunth (Asteraceae) on an altitudinal gradient

Abstract

The effects of climate change on biodiversity include the displacement, increase, reduction, or extinction of species. Potential distribution models allow us to identify their ecological niche and infer species’ responses to climate change. The objectives of this work were to model the potential distribution of Baccharis conferta under climate change scenarios, to determine the area that will be protected in the future in Natural Protected Areas (NPA), and to evaluate the effect on the altitudinal change of the species under climate change scenarios. MaxEnt modeled the current potential distribution and scenarios for the years 2050 and 2070, with concentrations of 538 and 936 ppm of CO₂. In addition, the areas lost, gained, and stable in both scenarios were compared. The variables most important in the distribution were the mean temperature of the driest season, the seasonality of temperature, and the precipitation of the coldest season. Despite being a species with a wide distribution in the Transverse Neovolcanic Axis, future scenarios show a reduction of up to 93 % of its current potential distribution, taking refuge at higher elevations. In addition, the area of B. conferta that will be protected in the future in NPA is exceptionally low, highlighting the need to expand or establish new ones based on future distribution models. NPA, especially those with altitudinal gradients and microclimates capable of mitigating climate change, play a crucial role as a refuge for biodiversity in temperate ecosystems. We observed a significant decrease in the elevation range between the present and all future scenarios, reducing in the future scenarios. Conservation planning must adapt to climate change predictions to ensure the survival of species such as B. conferta.