A comparative modelling study of two Brazilian rain catchments suggests that climate change will have contrasting effects on future soil erosion in the Amazon and Cerrado. The findings have implications for land management in both biomes in the coming decades.
The research, published in the International Journal of Hydrology Science and Technology, used rainfall records and projections from NASA’s Earth Exchange Global Daily Downscaled Projections (NEX-GDDP). This allowed the team to estimate soil loss under different scenarios.
Soil loss, the amount of soil removed by erosion, was calculated using the Universal Soil Loss Equation (USLE), which estimates erosion driven by rainfall, land cover, topography, and soil properties. Rainfall erosivity refers to rain’s capacity to detach and transport soil particles.
The team explains that the Cerrado is a biodiverse savanna, while the Amazon regulates rainfall through evapotranspiration, the transfer of water from land to the atmosphere. Differences in rainfall, elevation and land use affect soil erosion patterns. The global circulation models (GCMs) of climate simulations suggest that shifting rainfall intensity will change erosion rates with heavier rainfall increasing soil loss risk.
In the Amazon catchment, soil loss historically ranges from just a few dozen kilograms per hectare each year to almost 20 tonnes per hectare per year. Soil erosion is predicted to increase by several per cent through the remainder of this century.
By contrast, soil loss in the Cerrado’s Piranhas River catchment has been from a hundred kilograms or so to almost 250 tonnes per hectare per year. The models predict that soil erosion will actually become less of a problem in the coming years despite the effects of climate change.
As such, there is a need to respond to the changes of the future in different ways in the two very different regions. In the Amazon catchment, rising erosion risk supports conservation measures such as terracing, no-till farming and crop rotation. While in the Cerrado catchment, simply maintaining current agricultural practices may help sustain reduced soil loss.
Sobral, R.V.S., Lobato, A.K.R., Soares, A.d.C.L., de Mendonça, L.M., Cruz, J.d.S. and Blanco, C. (2026) ‘Impact of climate change on soil loss in small catchments in the Amazon and Cerrado biomes’, Int. J. Hydrology Science and Technology, Vol. 21, No. 4, pp.417–436.