Post-wildfire recovery of forest vegetation, soil, and hydrological responses: A review

Wildfires have been a major forest disturbance, especially under climatic change. Forest regeneration is a constant process, following each disturbance. However, little is known about its duration and the subprocesses involved. Furthermore, wildfire regimes as well as the local characteristics of each disturbed forest system have a drastic effect on forest regeneration. Abiotic factors also interact with regeneration processes and their restoration is crucial for the forest system balance. Aiming to explore forest post-wildfire recovery processes and monitoring techniques, a conceptual model focused on three environmental conditions is adopted for studying interactions among initial forest conditions, wildfire regime and recovering forest system. Therefore, forest systems are divided into three main elements consisting of vegetation, soil and hydrology. Post-wildfire recovering processes and successional stages are analyzed and measures for defining wildfire regime and its interactions with forest system restoration are scrutinized. Furthermore, the restoration of the abiotic environment – consisting of soil and hydrology – is analyzed. Seven post-wildfire successional stages were identified. Wildfire regimes under climate change favor shifts from conifers to deciduous trees and from forests to shrublands. In addition, wildfire intensity can serve as a measure for soil recovery, with higher intensities having severe impacts on soil structure, nutrients and erosion. Accordingly, wildfire severity can serve as a measure for estimating hydrological effects, with extreme magnitudes being responsible for floods and short-term water pollution. On an average wildfire regime and a temperate climate, abiotic factors can be restored in a decade, while 15 to 25 years are needed for the recovery of vegetation composition. • Seven post-wildfire successional stages were identified. • Wildfires stimulate vegetation shifts and forest ecological degradation. • Vegetation composition recovers quickly but structure slowly. • On average, soil and hydrology can be restored in a decade.