Shrub recovery after fuel reduction treatments in a gorse shrubland in northern Spain

Land managers need information about the environmental effects of fuel reduction techniques to select the most appropriate treatments in terms of conservation of ecosystem diversity and function. In this study, shrub cover recovery was monitored during the first four years after prescribed burning, clearing and mastication in a gorse shrubland dominated by Ulex gallii Planch. in northern Spain. Twelve experimental plots were installed just before treatments where plant cover was measured. All plant species present were identified, their frequency recorded and alpha diversity, richness and evenness determined. No differences between fuel treatments were observed for total shrub cover during the duration of the study. However, at the end of the study period, cover by Ericaceae shrubs and grasses was almost two times higher than the pre-treatment values, for all treatments. The treatments did not have different effects on gamma diversity or evenness during the four year interval, although higher species richness was measured in the burned plots than in the masticated or cleared ones throughout the study period. However, a redundancy analysis showed that the variation in species frequency during the study period was not related to the type of treatment applied. Fuel treatments significantly affected the shrubland under study in the short and medium term. The increase in Ericaceae shrubs and grasses cover may shift the long-term community composition. Long-term studies are required to establish whether the observed response lasts in time.