Distribution shifts, potential refugia, and the performance of protected areas under climate change in the <i>Araucaria</i> moist forests ecoregion
Daniel Dutra Saraiva, Luíz Fernando Esser, Daniel Grasel, João André Jarenkow
Abstract
Abstract Aim Araucaria moist forests are particularly vulnerable to climate change due to their strict climatic requirements and patchy distribution. Therefore, identifying areas where these forests are expected to lose or retain climatically suitable space (i.e., climate change refugia) is urgently required. Here, we modeled the current and future climatic suitability for Araucaria moist forests aiming: (a) to identify areas of suitable climate (i.e., in situ and ex situ refugia); (b) to identify areas of climate retraction; and (c) to assess the effectiveness of protected areas to capture climatically suitable space. Location Araucaria moist forests ecoregion, southern Brazil and northeast Argentina. Methods We mapped the potential distribution of Araucaria moist forests using an ensemble forecasting approach with 18 indicator tree species (all wet‐ and cold‐adapted taxa), six algorithms, eight global circulation models, three representative concentration pathways (RCPs 4.5, 6.0, and 8.5), and three periods (current, 2050, and 2070). Results We predicted substantial losses of future climatic suitability across almost the entire range where these forests occur, ranging from 43% to 64% under optimistic (RCP4.5/2050) and high‐emissions (RCP8.5/2070) scenarios. We found that the protected‐areas network captured only 3% of the climatically suitable space under current conditions. We found that only 4% (top 1% of cells) and 12% (top 5% of cells) of the potential refugia would be protected in the future, with less than half of their areas corresponding to in situ refugia. Conclusions Projected losses of potential distribution and the low efficacy of protected areas to buffer climate change impacts point to a high‐risk scenario for Araucaria moist forests in the near future. Cold‐adapted tree species likely will face increased extinction risk, especially as climate change will interact with other anthropogenic drivers.