Climate change threatens native potential agroforestry plant species in Brazil

Abstract

Climate change is one of the main drivers of species extinction in the twentyfirst-century. Here, we (1) quantify potential changes in species' bioclimatic area of habitat (BAH) of 135 native potential agroforestry species from the Brazilian flora, using two different climate change scenarios (SSP2-4.5 and SSP5-8.5) and dispersal scenarios, where species have no ability to disperse and reach new areas (non-dispersal) and where species can migrate within the estimated BAH (full dispersal) for 2041-2060 and 2061-2080. We then (2) assess the preliminary conservation status of each species based on IUCN criteria. Current and future potential habitats for species were predicted using MaxEnt, a machine-learning algorithm used to estimate species' probability distribution. Future climate is predicted to trigger a mean decline in BAH between 38.5-56.3% under the non-dispersal scenario and between 22.3-41.9% under the full dispersal scenario for 135 native potential agroforestry species. Additionally, we found that only 4.3% of the studied species could be threatened under the IUCN Red List criteria B1 and B2. However, when considering the predicted quantitative habitat loss due to climate change (A3c criterion) the percentages increased between 68.8-84.4% under the non-dispersal scenario and between 40.7-64.4% under the full dispersal scenario. To lessen such threats, we argue that encouraging the use of these species in rural and peri-urban agroecosystems are promising, complementary strategies for their long-term conservation.

Figure 1

Loss (red) and gain (blue) of BAH for 135 native potential agroforestry plant species in Brazil, obtained by stacking ENM binary predictions, based on different climate scenarios and years. Legend indicates the number of species. Maps created with custom R script. Version R 4.1.1 (https://www.R-project.org/). Base map source (Brazilian states shapefile) obtained from the Brazilian Institute of Geography and Statistics (https://www.ibge.gov.br/).

Figure 2

Decline of BAH by climate change for A. angustifolia, a species traditionally combined with other agricultural crops from Atlantic Forest. a) Current habitat suitability. Blue to red indicates the increase of suitability b-c) Future suitable habitats based on SSP2-4.5 and SSP5-8.5 scenarios for 2061–2080. Wine red colour indicates the remaining BAH. Estimated BAH is surrounded by dotted lines in royal blue colour. Maps created with custom R script. Version R 4.1.1 (https://www.R-project.org/). Base map source (Terrestrial biomes shapefile) obtained from the Brazilian Ministry of the Environment (https://www.gov.br/mma/).

Figure 3

Percentage of Brazilian agroforestry plant species potentially qualified in a threat categories VU + EN + CR, and in separate categories Vulnerable (VU), Endangered (EN) and Critically Endangered (CR), under two different climate change scenarios (SSP2-4.5 and SSP5-8.5) for the following time periods: 2041–2060 and 2061–2080, assuming two dispersal scenarios: (a) non-dispersal and (b) full dispersal.

Figure 4

Native potential agroforestry plant species changing from a current assessed IUCN category or Not Evaluated (NE) to a threat category, Vulnerable (VU), Endangered (EN) and Critically Endangered (CR), based on different major uses due to climate change.