RT info:eu-repo/semantics/article T1 Mapping Soil Burn Severity at Very High Spatial Resolution from Unmanned Aerial Vehicles A1 Beltrán Marcos, David A1 Suárez-Seoane, Susana A1 Fernández Guisuraga, José Manuel A1 Fernández García, Víctor A1 Pinto Prieto, Rayo A1 García Llamas, Paula A1 Calvo Galván, María Leonor A2 Ecologia K1 Ecología. Medio ambiente K1 Ingeniería forestal K1 Ceniza K1 Suelo K1 Índices de agua K1 2417.13 Ecología Vegetal K1 2511.06 Conservación de Suelos AB The evaluation of the effect of burn severity on forest soils is essential to determine the impact of wildfires on a range of key ecological processes, such as nutrient cycling and vegetation recovery. The main objective of this study was to assess the potentiality of different spectral products derived from RGB and multispectral imagery collected by unmanned aerial vehicles (UAVs) at very high spatial resolution for discriminating spatial variations in soil burn severity after a heterogeneous wildfire. In the case study, we chose a mixed-severity fire that occurred in the northwest (NW) of the Iberian Peninsula (Spain) in 2019 that affected 82.74 ha covered by three different types of forests, each dominated by Pinus pinaster, Pinus sylvestris, and Quercus pyrenaica. We evaluated soil burn severity in the field 1 month after the fire using the Composite Burn Soil Index (CBSI), as well as a pool of five individual indicators (ash depth, ash cover, fine debris cover, coarse debris cover, and unstructured soil depth) of easy interpretation. Simultaneously, we operated an unmanned aerial vehicle to obtain RGB and multispectral postfire images, allowing for deriving six spectral indices. Then, we explored the relationship between spectral indices and field soil burn severity metrics by means of univariate proportional odds regression models. These models were used to predict CBSI categories, and classifications were validated through confusion matrices. Results indicated that multispectral indices outperformed RGB indices when assessing soil burn severity, being more strongly related to CBSI than to individual indicators. The Normalized Difference Water Index (NDWI) was the best-performing spectral index for modelling CBSI (R2cv = 0.69), showing the best ability to predict CBSI categories (overall accuracy = 0.83). Among the individual indicators of soil burn severity, ash depth was the one that achieved the best results, specifically when it was modelled from NDWI (R2cv = 0.53). This work provides a useful background to design quick and accurate assessments of soil burn severity to be implemented immediately after the fire, which is a key factor to identify priority areas for emergency actions after forest fires. PB MDPI SN 1999-4907 LK http://hdl.handle.net/10612/12947 UL http://hdl.handle.net/10612/12947 NO Artículo DS BULERIA. Repositorio Institucional de la Universidad de León RD 27-abr-2024