Entendendo a distribuição atual e futura da cianobactéria Raphidiopsis raciborskii no Brasil

Abstract

Raphidiopsis raciborskii is a tropical cyanobacterium that has gained notoriety for being in expansion around the world, for forming potentially toxic blooms and for being able to tolerate different environmental conditions, hence, it is believed that this species is benefiting from climate change since it was found even in temperate regions. In Brazil, the invasion of the species was recorded mainly in public supply reservoirs, which causes great concern not only about the impacts on biodiversity but also on human health. The present study investigated the major climatic conditions that possibly influences the current distribution and future potential expansion of R. raciborskii, using the ecological niche modeling approach to estimate the areas suitable for occurrence in the country, connecting the areas of occurrence already known to climatic variables inherent to the ecology of the species and to climate scenarios predicted for the Intergovernmental Panel on Climate Change (IPCC) with focus on the years 2040 and 2100 projections. The Annual mean temperature, the mean diurnal range and the annual precipitation were the variables that contributed the most to the distribution of the species. The models obtained showed that the habitat suitability for R. raciborskii was maintained along the entire Brazilian coastal line in different watersheds. However, the current estimated scenario is better suited for the species than the scenarios predicted for the future.