Long-term forest management after wildfire (Catalonia, NE Iberian Peninsula)

Abstract

Studies of post-fire soil status in Mediterranean ecosystems are common; however, few have examined the effects of long-term forest management after a wildfire on physicochemical soil properties. Here, we analyzed differences in soil properties attributable to long-term post-fire management and assessed the sustainability of these management practices in relation to the soil properties. The study area is located in Odena in the northeast region of the Iberian Peninsula consisted of the control forest (burned more than 30 years ago), low density forest (LD; burned in a wildfire in 1986 and managed in 2005) and high density forest (HD; burned in a wildfire in 1986 and no managed). For soils from each plot, we measured soil water repellency, aggregate stability, total nitrogen (TN), soil organic matter (SOM), inorganic carbon (IC), pH, electrical conductivity, extractable calcium, magnesium, sodium, potassium (K), phosphorus, aluminum (Al), manganese (Mn), iron (Fe), zinc, copper, boron, chrome, silicon and sulfur and calculated the ratios of C/N, Ca + Mg/(Na + K)1/2, Ca/Al and Ca/Mg. Significant differences were found in TN, IC, SOM, pH, K, Al, Mn, Fe and C/N ratio (p < 0.05). All soil properties were found to have largely recovered their pre-fire values. Soils were affected by the post-fire management practices implemented 20 years after the fire, as reflected in their respective physicochemical properties, so that soil properties at the control and LD sites are more similar today than those at the control and HD sites. Thus, sustainable forest management can overcome soil degradation in areas affected by wildfire in the medium- and long-term by improving soil properties.