Impact of wildfires on aboveground biomass in shrublands of Lagadas county in northern Greece

Large forested areas are destroyed by wildfires in Greece each year. A significant part of these areas comprises rangelands that are degraded considerably. events lead to low biodiversity, soil erosion, water runoff and low soil productivity. The present study was carried out in an area of 563.2 ha, located at Lagadas county, which was burnt in 2007. The dominant shrub species of the area are kermes oak (Quercus coccifera) and wild pear (Pyrus spinosa). In burned and unburned shrublands of three cover types, namely open (10-40%), medium (41-70%), and dense (71-100%) the aboveground biomass of both herbaceous and woody species was estimated at the end of the second growing season since the wildfire. It was found that the herbaceous biomass was increased considerably two years after the fire apparently due to the reduction of woody plants. Woody biomass however was lower in the burnt than in the unburnt area. Nevertheless, the total biomass was the same in burned and unburned areas because of the higher yield of herbaceous vegetation which balanced the reduction of the woody biomass. Also, medium shrublands produced significantly more herbaceous biomass than the open ones as the latter were exposed to heavier grazing by livestock.