A study conducted by Brazilian researchers reveals that climate change will have significant impacts on the Caatinga, a semi-arid shrubland and thorn forest biome in Brazil's Northeast region.
The consequences include species loss, the substitution of rare plants with more adaptable vegetation, biotic homogenization, increasing aridity, and potential desertification in some areas. The research, reported in the Journal of Ecology, was conducted by researchers from the State University of Campinas, the Federal University of Paraíba, the Federal University of Pernambuco, the Federal University of Viçosa, and the Federal Institute of Goiás.
The researchers compiled a comprehensive database of over 400,000 occurrence records for approximately 3,000 plant species in the biome. They then categorized the species into woody (trees, shrubs, palms, and woody vines) and non-woody (herbs, herbaceous vines, and succulents) groups. Using models and simulations, they projected the potential responses of plant species in the Caatinga to future climate variations.
The results showed that by 2060, 99% of plant assemblages in the Caatinga will experience species loss due to increasing aridity and rising temperatures. The hot and dry climate will favor the growth and spread of shrubs and grasses, leading to the replacement of many tree species. This shift in vegetation will impact essential ecosystem services such as photosynthesis, air renewal, and carbon storage.
Mountainous areas within the Caatinga, such as Chapada Diamantina and Chapada do Araripe, will be particularly affected. Lowland species are expected to migrate to higher ground as temperatures rise, while highland species face the risk of extinction. Biotic homogenization, where previously distinct plant communities become more similar, will occur in approximately 40% of plant assemblages, resulting in a simplification of their composition.
To mitigate the adverse effects of climate change and human activities like deforestation and habitat destruction, the researchers emphasize the need for long-term conservation plans at the macro-level. These plans could focus on landscape restoration and connectivity to facilitate the dispersal of species to more suitable areas. However, if biodiversity continues to be compromised, the resources and ecological balance of the Caatinga will be further threatened.
Source: Mario R. Moura et al, Pervasive impacts of climate change on the woodiness and ecological generalism of dry forest plant assemblages, Journal of Ecology (2023).
Source: FAPESP