Soil erosion assessment in the Amazon basin in the last 60 years of deforestation

Nelva B Riquetti; Samuel Beskow; Li Guo; Carlos R Mello

doi:10.1016/j.envres.2023.116846

Soil erosion assessment in the Amazon basin in the last 60 years of deforestation

Environ Res. 2023 Nov 1;236(Pt 2):116846. doi: 10.1016/j.envres.2023.116846. Epub 2023 Aug 6.

Authors

Nelva B Riquetti¹, Samuel Beskow¹, Li Guo², Carlos R Mello³

Affiliations

¹ Water Resources Graduate Program, Federal University of Pelotas, Campus Porto, Rua Gomes Carneiro, 1, 96010-610, Pelotas, RS, Brazil.
² State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource and Hydropower, Sichuan University, Chengdu, 610065, China.
³ Water Resources Department, Federal University of Lavras, Campus Universitário, CP 3037, 37200-900, Lavras, MG, Brazil; Department of Agricultural and Biological Engineering, College of ACES, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. Electronic address: crmello@ufla.br.

PMID: 37553028
DOI: 10.1016/j.envres.2023.116846

Abstract

Anthropic activities in the Amazon basin have been compromising the environmental sustainability of this complex biome. The main economic activities depend on the deforestation of the rainforest for pasture cattle ranching and agriculture. This study analyzes soil erosion to understand how deforestation has impacted the Amazon basin in this context, using three land-use temporal maps (1960, 1990, 2019) through the revised universal soil loss equation (RUSLE). Our results point to a significant influence of deforestation due to the expansion of agricultural and livestock activities on soil erosion rates in the Amazon Basin. The average soil erosion rate has increased by more than 600% between 1960 and 2019, ranging from 0.015 Mg ha^-1 year^-1 to 0.117 Mg ha^-1 year^-1. During this period, deforestation of the Amazon rainforest was approximately 7% (411,857 km²), clearly the leading cause of this increase in soil erosion, especially between 1990 and 2019. The south and southeast regions are the most impacted by increasing soil erosion, in which deforestation was accelerated for expanding agriculture and livestock activities, mainly in the sub-basins of the Madeira, Solimões, Xingu, and Tapajós that present soil erosion increases of 390%, 350%, 280%, and 240%, respectively. The sub-basins with the highest sediment delivery rate (SDR) are under the influence of the Andes, highlighting Solimões (27%), Madeira (13%), and Negro (6%) due to the increase in the soil erosion rate increase in these sub-basins.

Keywords: Amazon LULC; Deforestation; Environmental quality; Sustainability; Water erosion.