Paleoecology and Climate Dynamics in Southeastern Brazil

The palaeoecology and climate dynamics of southeastern Brazil encompass a complex interplay between vegetation shifts, hydrological changes and human interactions over the late Quaternary. This region, characterised by the Atlantic Forest and adjacent highland grasslands, has undergone marked reorganisations during glacial and interglacial cycles. Fossil pollen, sedimentary and isotopic records reveal fluctuations in temperature and precipitation driven by global ice‐volume changes, the positioning of the South Atlantic Convergence Zone and variations in the South American summer monsoon. These climate drivers have shaped forest refugia, corridor formation and species migrations between the Andes, Amazonia and coastal domains. Late Holocene trends further reflect anthropogenic land‐use, with forest expansion and contraction responding to demographic shifts. Understanding these past dynamics not only informs models of biodiversity resilience under future warming but also guides conservation strategies and water‐resource management within one of the most biodiverse and threatened tropical biomes.

Research from Nature Portfolio

Recent studies have reconstructed Last Glacial Maximum vegetation connectivity across South America by analysing pollen assemblages and modern niche spaces, revealing five distinct migration pathways linking Andean, Amazonian and Atlantic forests. These findings indicate that cool and moist taxa dispersed across emergent continental shelves under lower sea levels, reshaping biodiversity patterns that persist today. Investigations of monsoon variability over the penultimate glacial period based on lake‐peat sediment sequences demonstrate shifts in mean annual temperature, biomass burning and forest composition driven by alternate monsoon intensification and southern atmospheric circulation. Such records highlight that tropical forest dynamics responded in decoupled ways to mid‐latitude glacial forcings. Further research into montane rainforest expansion during Heinrich Stadial 1 utilising palynological data and species distribution models confirms long‐distance plant migrations under cooler, wetter conditions, elucidating the origins of modern disjunct montane plant distributions in the Brazilian Highlands.

Paleoecology and Climate Dynamics in Southeastern Brazil publication trend

The graph below shows the total number of articles in paleoecology and climate dynamics in southeastern brazil across all publications each year (not limited to Nature Index journals).

Technical terms

Palaeodistribution modelling: Simulation of past species ranges using climate reconstructions and ecological niche data.

Palynology: Study of fossil pollen and spores to reconstruct past vegetation and climate.

South American summer monsoon (SASM): Seasonal circulation system driving rainfall over tropical South America.

South Atlantic Convergence Zone (SACZ): A key band of convective rainfall extending from the Amazon to the South Atlantic.

Last Glacial Maximum (LGM): Period around 21,000 years ago when global ice sheets were at their maximum extent.

Organic soils (Histosols): Peat‐rich soils with high organic matter content, preserving stratified environmental records.

Radiocarbon dating: Technique for determining the age of organic material by measuring carbon‐14 decay.

References

1. Evaluating the impact of historical climate and early human groups in the Araucaria Forest of eastern South America. Ecography (2024).
2. A North–South Dipole Response of the South Atlantic Convergence Zone During the Mid‐Holocene. Geophysical Research Letters (2023).
3. Humid and cold forest connections in South America between the eastern Andes and the southern Atlantic coast during the LGM. Scientific Reports (2024).
4. Organic Soils: Formation, Classification and Environmental Changes Records in the Highlands of Southeastern Brazil. Sustainability (2023).
5. Uncoupling human and climate drivers of late Holocene vegetation change in southern Brazil. Scientific Reports (2018).
6. Shut down of the South American summer monsoon during the penultimate glacial. Scientific Reports (2020).
7. Brazilian montane rainforest expansion induced by Heinrich Stadial 1 event. Scientific Reports (2019).
8. Histosols in an Upper Montane Environment in the Itatiaia Plateau. Revista Brasileira de Ciência do Solo (2016).