Wildfires are major disturbances in Mediterranean landscapes, significantly increasing soil erosion risk by removing protective vegetation cover and disrupting sediment regulation functions at the catchment scale. Regarding post-fire erosion risk, uncertainty remains in how different cover-management (C) factor estimation methods influence predicted soil loss. This study investigates the spatiotemporal variability of the C-factor following three major wildfire events (2007, 2022, and 2024) in the Pinios Dam drainage basin, Western Greece, by comparing static land cover-based (CORINE) assignments and dynamic index-based (NDVI, EVI, PVI, SAVI) C-factor values. Burn severity was assessed using the differenced Normalized Burn Ratio (dNBR) while RUSLE factors R, K, LS, and P were held constant to isolate the sensitivity of alternative C-factor formulations under controlled baseline conditions. All methods showed post-fire increase in C-factor values, with the 2007 wildfire showing the most severe impacts. NDVI-based C-factor estimates demonstrated the strongest response to vegetation loss, EVI- and PVI-based estimates also captured post-fire changes but more conservatively, while SAVI-based estimates were consistently higher but less variable. In contrast, land cover-based estimates reflected the general pattern of post-fire vegetation cover reduction but failed to represent the spatial variability associated with differing burn severity. By linking C-factor behavior to burn severity gradients and quantifying the resulting differences in predicted soil loss, this study provides a comparative evaluation of the sensitivity of commonly used vegetation indices for post-fire change detection, a methodological evaluation of static versus dynamic C-factor representations, and a transferable cloud-based workflow for post-fire erosion assessment in Mediterranean environments. • Impact of three major wildfires on soil erosion was quantified using burn severity and multiple C-factor methods in RUSLE model. • Pre- and post-fire land cover-based (CORINE) C-factors were compared with dynamic index-based C-factors derived from NDVI, EVI, PVI and SAVI. • Index-based C-factors exhibit stronger responsiveness to burn severity gradients and spatio-temporal variability of C-factor than land cover-based method. • Propose an adaptable remote-sensing and cloud-based framework for C-factor estimates that enables robust post-fire erosion assessment.
Michalopoulou et al. (Tue,) studied this question.