Abstract

first_page settings Order Article Reprints Open AccessArticle Sediment Load Decreases After the Historical 2017 Megafire in Central Chile: The Purapel in Sauzal Experimental Watershed Case Study and Its Implications for Sustainable Watershed Management by Roberto Pizarro 1,2,3, Ben Ingram 4,5 [ORCID] , Alfredo Ibáñez 1,2, Claudia Sangüesa 1,2, Cristóbal Toledo 1, Juan Pino 6, Camila Uribe 1, Edgard Gonzales 7 [ORCID] , Ramón Bustamante-Ortega 1 and Pablo A. Garcia-Chevesich 8,9,* [ORCID] 1 UNESCO Chair on Surface Hydrology, University of Talca, Lircay s/n, Talca 3465000, Chile 2 Centro Nacional de Excelencia Para la Industria de la Madera (CENAMAD)—ANID BASAL FB210015, Pontificia Universidad Católica de Chile, Santiago 7810128, Chile 3 Faculty of Forest Science and Nature Conservancy, University of Chile, Santa Rosa 10350, Santiago 8820808, Chile 4 Department of Interactive Visualization and Virtual Reality, Faculty of Engineering, Universidad de Talca, Talca 3460000, Chile 5 Faculty of Energy and Applied Sciences, Cranfield University, Cranfield MK43 0AL, UK 6 Magíster en Gestión Tecnológica, Universidad de Talca, Talca 3460000, Chile 7 Facultad de Geología, Geofísica y Minas, Universidad Nacional de San Agustín de Arequipa, Arequipa 04001, Peru 8 Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401, USA 9 Intergubernamental Hydrological Programme, United Nations Educational, Scientific, and Cultural Organization, Luis Piera 1992, Edificio Mercosur, 2do Piso, Montevideo 11200, Uruguay * Author to whom correspondence should be addressed. Sustainability 2025, 17(22), 9930; https://doi.org/10.3390/su17229930 Submission received: 4 September 2025 / Revised: 9 October 2025 / Accepted: 30 October 2025 / Published: 7 November 2025 Download keyboard_arrow_down Browse Figures Versions Notes Abstract Forests play a critical role in regulating hydrological processes and reducing soil erosion and sediment load. However, climate change has increased the frequency and severity of wildfires, which can significantly impact these ecosystem services. A historical megafire burned in January of 2017 in Central Chile, affecting the Purapel in Sauzal experimental watershed (an area dominated by Pinus radiata plantations), providing a unique opportunity to study post-fire sediment load dynamics. We hypothesized that sediment load would significantly increase following the wildfire, especially in areas with exotic commercial plantations. To test this, we analyzed daily sediment load and streamflow data collected the Purapel River during the 1991–2018 period, as well as other variables. Descriptive statistics and a sediment rating curve model were used to assess temporal variations in sediment load. Contrary to expectations, results showed no significant increase in sediment concentration following the devastating 2017 wildfire event. In fact, the Mann–Kendall test revealed a significant decreasing trend in winter sediment production over the study period. These findings may be explained by a reduction in precipitation during the mega-drought of the 2010s and, importantly, a rapid and dense post-fire pine seedling regeneration. This study highlights the complex interactions between climate, vegetation, and geomorphic processes, as well as the need for further research on post-fire sediment dynamics in Mediterranean plantation forests.