Impacto del cambio de uso del suelo en la escorrentía superficial y la conductividad hidráulica: estudio de caso en la cuenca del río Baché, Huila (2004-2024)

Contextualization: The study analyzed surface runoff variations in the Baché River basin (Huila, Colombia) caused by land-use changes over three periods (2004, 2014, 2024). Knowledge gap: Integrated analyses of how forest conversion to agriculture affected the hydrological response in volcanic soils (Andisols and Inceptisols) were lacking, despite covering 49.8% of the basin. Objective: To evaluate the impact of changes in vegetation cover on hydraulic conductivity (Ks) and runoff, using hydrological models and satellite data. Methodology: Landsat image processing (4/7/8, 30 m) in ArcGIS; digitalization of digital elevation models. HEC-HMS modeling was used to generate hydrological scenarios, and Ks was calculated, and flow rates were compared. Results: Progressive reduction in Ks: 2.1 mm/h (2004) to 1.59 mm/h (2024); Increase in runoff: 899 m³/s (2004, 44.29% forest) to 1619 m³/s (2024, 70.9% agriculture), with a greater impact on volcanic soils near the drainage network. Conclusions: Forest conversion has reduced soil water retention capacity by 47% in 20 years. The integrated GIS modeling approach has proven effective in assessing hydrological impacts, highlighting the need for volcanic soil conservation policies.