Recovery of a soil under different vegetation one year after a high intensity wildfire

Studies on soil recovery in fragile ecosystems following high intensity wildfires are scarce. The aim of the present investigation is to evaluate the impact of a high intensity wildfire in an ecosystem under different vegetation (shrubland and pinewood) located at Vilardevós (Galicia, NW Spain) and highly susceptible to suffer soil erosion due to the steep relief and high erositivity of the rainfall. Soil samples were collected from the A horizon (0-5 cm) 1 year after the fire and soil quality was evaluated by analysis of several physical, chemical and biochemical properties measured in the fraction < 2 mm. The results showed marked effects of the wildfire on most properties analyzed even 1 year after the fire; however, a different effect both in the trend (positive, negative) and magnitude were observed, depending on the soil property analyzed. In general, the sensitivity to detect fire induced changes followed the order: biochemical properties > chemical properties > physical properties. The data also showed that the fire impact was different depending on the soil vegetation considered (shrubland and pinewood). Moreover, the data confirmed the slow soil recovery in this fragile ecosystem and, therefore, the need of adopting post-fire stabilisation and rehabilitation treatments in order to minimize the post-fire erosion and soil degradation.