Research from the University of Liverpool, published in Nature Ecology and Evolution, reveals that four decades of tree records across the Amazon and Andes show climate change is profoundly reshaping tropical forests in uneven ways. While overall tree diversity appears stable, specific regions are experiencing significant losses or gains in species, highlighting the complex impact on the Amazon forest.
This extensive study, led by Dr. Belen Fadrique, analyzed data collected by hundreds of botanists and ecologists from 406 long-term floristic plots across ten South American countries since the 1970s. The findings, highlighted in a ScienceDaily report on January 25, 2026, provide one of the most comprehensive assessments of how these biologically rich forests are adapting to shifting global environmental conditions.
The research challenges the notion of uniform climate change impacts, instead showing a mosaic of responses. It underscores the critical need for nuanced understanding and targeted conservation efforts as plant species face limited options: adapt, shift ranges, or decline.
Regional shifts in Amazon forest diversity
The apparent stability in total species richness across South America masks dramatic regional disparities. Forests exposed to higher temperatures, drier conditions, and stronger seasonal changes are consistently losing tree species. This trend is particularly evident in the Central Andes, the Guyana Shield, and parts of the Central Eastern Amazon, where most monitoring plots recorded declines.
Conversely, other areas, such as the Northern Andes and Western Amazon, have seen an increase in tree species. The study emphasizes that rainfall levels and seasonal rainfall patterns play a role as critical as rising temperatures in shaping these diverse regional outcomes. Dr. Fadrique notes, “Our work assessing species responses to climate change points to profound changes in forest composition, and species richness at multiple scales.”
Flavia Costa, a Professor at INPA (Instituto Nacional de Pesquisas da Amazônia) in Brazil, stressed the importance of these localized findings. “This study underscores the uneven impacts of climate change on tree diversity across different tropical forests, highlighting the need for specific monitoring and conservation efforts in each region,” she stated.
The Andes: A potential climate refuge
A significant discovery from the forty years of forest data is the identification of the Northern Andes as a potential “refuge” for tree species. As environmental conditions deteriorate in other areas, this region may offer shelter for species displaced from surrounding forests, becoming a vital biodiversity hotspot under increasing climate pressure.
Professor Oliver Phillips of the University of Leeds, who leads the pan-Amazon RAINFOR network, highlighted the added threat of deforestation to these already vulnerable ecosystems. He asserted, “Our findings stress the vital links between preserving forests, protecting biodiversity, and fighting climate change.”
Phillips added a crucial point: “It is especially critical to protect remaining forests where the Amazon meets the Andes. Only if they stay standing can they offer a long-term home to species in adjacent lowlands.” This underscores the urgency of conservation actions in these transitional zones to maintain the resilience of the Amazon forest.
The long-term data provides an indispensable window into the Amazon’s future, revealing a landscape undergoing profound, yet regionally varied, transformation. Understanding these specific patterns of loss and gain is paramount for developing effective, localized conservation strategies that safeguard the planet’s most biodiverse tropical forests against the escalating impacts of climate change.
