The impacts of the exposure of cactus species of the genus Tacinga to climate change in the Caatinga biome

Abstract

Although some studies have investigated the effect of climate change in the Caatinga biome, Brazil, its impacts on cactus species are yet to be understood entirely. We assessed if cactus species in the Caatinga biome will benefit from or be harmed by climate change in the coming decades. We modeled the distribution of Tacinga inamoena and Tacinga palmadora, two cactus species native to seasonally dry tropical forest. We evaluated these species’ range dynamics in two Shared Socioeconomic Pathways (SSP), SSP2 and SSP5, for two time periods centered in 2050 and 2070. For this purpose, we used the Maximum Entropy and Boosted Regression Trees tools to model the species distribution. The results indicated a continuous and significant contraction of the species range in the face of climate changes. We estimated that 65% of the range of T. inamoena and 27% of T. palmadora would be lost in the most critical scenario, SSP5/2070. Climate variables, such as annual precipitation and maximum temperature of warmest month, mainly drove this contraction. Results showed a high overlap in potential refugia areas with the target species. Our results can help protect refugia for cacti species, especially those of the genus Tacinga, throughout the Caatinga biome.

Keywords:
Seasonally dry tropical forest; climate refugia; suitable climate area; webbed cactus species; species distribution model