Human Impact on Madagascar's Late Holocene Ecosystems

Madagascar’s Late Holocene record reveals a complex interplay between natural climatic shifts and escalating human influence. Initial human arrival around 1,300–1,100 years ago coincides with the onset of deforestation, fire use and the introduction of domesticated animals. These activities precipitated the extinction of endemic megafauna—elephant birds, pygmy hippopotamuses and giant tortoises—through a combination of hunting pressure, habitat conversion and competition with livestock. As agro-pastoral communities expanded, grasslands replaced dry deciduous forest, soil erosion intensified and sediment loads in floodplains surged. In the highlands, the formation of deep gullies (lavaka) accelerated under combined climatic drying and anthropogenic disturbance, further destabilising watersheds. Coastal and inland lakes record marked shifts in pollen, diatom and charcoal assemblages, documenting the gradual decline of native tree taxa and the rise of fire-adapted grasses. These transformations have reshaped terrestrial and freshwater ecosystems, reduced biodiversity and altered hydrological regimes. Understanding this trajectory is vital for informing restoration efforts, sustainable land-use planning and mitigation of ongoing environmental change in one of the world’s most distinctive biodiversity hotspots.

Research from Nature Portfolio

Recent studies have presented the most complete Holocene speleothem record from north-western Madagascar, obtained from stalagmites in the Anjohibe cave system. This archive demonstrates that multi-millennial precipitation patterns in the region track broader monsoon activity, while centennial-scale anomalies reflect zonal sea-surface temperature gradients in the Indian Ocean rather than meridional shifts in monsoon belts. By establishing a detailed chronology of wet and dry intervals, this work provides an essential climatic baseline against which the timing and intensity of human-induced landscape change can be assessed.

Human Impact on Madagascar's Late Holocene Ecosystems publication trend

The graph below shows the total number of articles in human impact on madagascar's late holocene ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Late Holocene: The most recent segment of the Holocene epoch, spanning roughly the last 5,000 years, during which human influence on the environment intensified.

Speleothem: Mineral deposits, such as stalagmites, formed in caves that can be analysed for chemical proxies of past climate.

Radiocarbon dating: A method for determining the age of organic materials by measuring the decay of carbon-14 isotopes.

Stable isotope analysis: The measurement of non-radioactive isotopes (e.g., carbon-13, nitrogen-15) in biological or geological samples to infer diet, climate and ecological interactions.

Lavaka: Deep, steep-sided erosion gullies common in Madagascar’s highlands, often exacerbated by human land use and climatic factors.

Palaeoenvironmental reconstruction: The practice of using sedimentary, biological and chemical indicators to infer past environmental and climatic conditions.

References

1. Zonal control on Holocene precipitation in northwestern Madagascar based on a stalagmite from Anjohibe. Scientific Reports (2024).
2. Late Holocene spread of pastoralism coincides with endemic megafaunal extinction on Madagascar. Proceedings of the Royal Society B (2021).
3. Under pressure: Rapid lavaka erosion and floodplain sedimentation in central Madagascar. The Science of The Total Environment (2021).
4. Influence of Late Holocene Climate Change and Human Land Use on Terrestrial and Aquatic Ecosystems in Southwest Madagascar. Frontiers in Ecology and Evolution (2021).