Analysis of the impact of watershed management practices, vegetation, and land use on soil erosion using EPM-IntErO modelling in Ceará’s semi-arid region

The semi-arid region of Ceará, located in Northeast Brazil, is typically characterized by low rainfall, high temperatures, and sparse vegetation – conditions generally associated with reduced soil erosion rates. However, the region's fragile soils, which are shallow, nutrient-poor, and particularly susceptible to degradation, exacerbate the erosion. This degradation poses a significant threat to soil fertility, agricultural productivity, and environmental sustainability in the area. The primary objective of this study was to quantify soil loss in Ceará and to challenge the prevailing assumption that semi-arid regions inherently experience minimal erosion due to limited rainfall. The Intensity of Erosion and Outflow (IntErO) model was used, in conjunction with remote sensing data and geographic information system (GIS) technologies. Through this approach, we estimated an average soil loss rate of 9.7 Mg ha⁻¹ yr⁻¹. The results indicate that 38% of Ceará’s land area experiences soil loss rates exceeding tolerance limits, particularly in regions lacking vegetation, as well as in agricultural lands and pastures. These elevated erosion rates are largely attributed to the area’s poor soil properties, occasional intense rainfall events, and unsustainable land management practices. The findings underscore the urgent need for improved management of soil erosion processes to address these challenges. Implementing targeted soil conservation strategies and policies that promote sustainable land use is essential for mitigating water erosion, safeguarding long-term agricultural productivity, and enhancing environmental and socioeconomic sustainability in semi-arid regions.