Post-fire salvage logging increases restoration costs in a Mediterranean mountain ecosystem

Abstract

Post-fire salvage logging (i.e. felling and removing burnt trees, often eliminating the remaining woody debris) is a practice routinely performed by forest managers worldwide. In Mediterranean-type ecosystems, salvage logging is considered a measure to reduce future reforestation costs, but this assumption remains largely untested. We made a cost analysis of different management schemes, addressing the immediate post-fire burnt-wood management as well as the costs and success of subsequent reforestation efforts. Two experimental 25-ha plots were established in a burnt pine reforestation of SE Spain, in which three replicates of three post-fire treatments were applied: non-intervention (NI), partial cut plus lopping (PCL; felling and lopping off the branches from most of the trees, leaving all biomass in situ), and salvage logging (SL). After 4 years, a mechanised reforestation was undertaken, and seedling mortality was monitored for 2 years. The cost of all management operations was recorded in situ, and the cost of re-planting the dead seedlings was estimated according to the expenses of previous reforestation. Initial cost of wood management was greatest in SL and zero in NI. Reforestation cost was highest in NI and lowest in SL, and seedling-mortality rates proved lowest in PCL (43 % vs. 51 % and 52 % in SL and NI, respectively). Considering all the post-fire management operations, salvage logging did not provide particular economic advantages for forest restoration, and had an overall cost of 3,436 ± 340 €/ha. By contrast, NI and PCL reduced total restoration costs by 50 and 35 %, respectively, and PCL indeed promoted restoration success. We suggest that the full cost of management operations needs to be considered when evaluating the economic implications of post-fire salvage logging.