Evaluating hydrological and soil erosion processes in different time scales and land uses in southern Brazilian paired watersheds

Abstract

ABSTRACTLand use is a driver for hydrological and soil erosion responses at the watershed scale. This study aimed to assess the hydrological and soil erosion processes in small watersheds under three different land uses, at three time scales. We investigated four small watersheds in southern Brazil: Agricultural North watershed (ANW), Agricultural South watershed (ASW), Eucalyptus watershed (EW), and Grassland watershed (GW). The SWAT (Soil and Water Assessment Tool) model was used to simulate streamflow (SF) and sediment yield (SY) at monthly, daily and hourly time scales. EW had the lowest SF and SY, whereas ANW showed the highest SY with an increase of 90% and ASW had the highest SF with an increase of 70%. The SWAT model had a satisfactory performance in all time scales and watersheds for SF and SY (NSE and R2 ≥ 0.3 and Pbias ≤ ± 39%). Overall, land use has a major impact on hydrological and soil erosion responses, and the magnitude of these processes depends on the time scale.KEYWORDS: agricultural hydrologySWATland use and coverhydrosedimentological temporal dynamics Editor A. Fiori; Associate Editor M. NonesEditor A. Fiori; Associate Editor M. NonesDisclosure statementNo potential conflict of interest was reported by the authors.Supplementary materialSupplemental data for this article can be accessed online at https://doi.org/10.1080/02626667.2023.2217333Additional informationFundingThis study was financed in part by the "Coordenação de Aperfeiçoamento de Pessoal de Nível Superior" (CAPES) – Finance Code 001, the Brazilian Council for Scientific and Technological Development (CNPq), "Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul" (Fapergs), and CMPC Celulose Riograndense.