Evaluation of log and branch barriers as post-fire rehabilitation treatments in a Mediterranean pine forest in Greece

Abstract

After severe fires, land management authorities in Mediterranean climate regions often apply post-fire rehabilitation measures intended to minimize on-site erosion and restore vegetation cover. The aim of our study was to evaluate the effectiveness of log and branch barriers as post-fire rehabilitation treatments after a severe fire in a Pinus brutia Ten. forest near Thessaloniki, Greece. We based our comparisons on the following woody perennial plants: Anthyllis hermanniae L., Asparagus acutifolius L., Cistus creticus L., Pinus brutia Ten., Quercus coccifera L. and Sarcopoterium spinosum (L.) Spach. Five years after fire, the post-fire treatments of log and branch barriers had no positive effect on groundcover. On the contrary, we found more exposed bare soil and rocks in the south treated plots compared to the untreated plots. A higher number of pine seedlings was observed on the treated south slopes and the untreated north slope. Higher pine mortality rates were observed in the south slopes and especially in the untreated site. Pine seedling growth was not affected by post-fire treatments. The highest density of C. creticus seedlings was found in the southern untreated plot, where the highest mortality rate was also observed. The construction of log and branch barriers had an adverse effect on Q. coccifera plants and consequently on the whole burned area revegetation process. Our study showed that the post-fire treatments had a negative effect on seedling density of A. hermanniae and A. acutifolius. The slope orientation affected the revegetation process and it was more successful on the north slopes. In conclusion, our results showed that the construction of log and branch barriers was not effective in post-fire ecosystem recovery.