Post‐fire salvage logging alters a key plant‐animal interaction for forest regeneration

Abstract

Abstract. Post-fire salvage logging is widely implemented worldwide, but there is an increasing concern about its potential impact on the ecosystem. Moreover, there is scant information about the effect of salvage logging on ecosystem processes mediated by species interactions. We manipulated a burnt pine forest to experimentally analyze the effect of burnt-wood management on the colonization of Holm oak (Quercus ilex) mediated by acorn dispersal by Eurasian jays (Garrulus glandarius). Three replicates of three treatments were established in an 18-ha plot: salvage logging (SL), non-intervention (NI), and partial cut plus lopping (PCL; felling and lopping most of the trees but leaving all the biomass in situ). We hypothesized that different burnt-wood management could alter jays' landscape perception and thus the pattern of seed dispersal and seedling recruitment. We monitored jay abundance in each treatment for three winters and three breeding periods, and jay flights of potential acorn dispersal between nearby oak trees and the treatments. We also searched for oak seedlings recruited in the experimental plot for five years following the fire. Jays were recorded significantly more times (87%) in NI, and movements to this treatment during the acorn dispersal period were also more frequent (81% of the flights). Oak seedlings were also more abundant in NI (ca. 55%) than in SL or PCL (ca. 25% each), despite a strong effect of small remnants of live pines. The results show that the burnt forest, if unsalvaged, still provides a suitable habitat for jays, while salvage logging reduces the strength of this key plant-animal interaction for oak natural regeneration. Nonintervention policies after a forest fire therefore provide the opportunity for adaptive management that helps reduce restoration costs and increase the resilience of the system.

Post-Fire Seedling Recruitment and Morpho-Ecophysiological Responses to Induced Drought and Salvage Logging in Pinus halepensis Mill. Stands

“…Also the abrupt insolation increase promoted by salvage logging increased summer mortality and reduced the growth of survival Aleppo pine (Pinus halepensis Mill.) seedlings [12], altered the plant-animal interaction [13], and reduced carbon sequestration [14] which could increase restoration costs [15].…”

Post-Fire Salvage Logging Imposes a New Disturbance that Retards Succession: The Case of Bryophyte Communities in a Macaronesian Laurel Forest

“…This represents a biological legacy with a critical role for the structure and functioning of the post-fire habitat [3][4][5], and with the potential to influence post-disturbance successional trajectories. In this sense, burnt logs, whether standing or felled, generate a vertical habitat structure that may promote secondary succession and accelerate ecosystem regeneration by promoting animal interactions such as seed dispersal [3,6], creating microhabitats that improve seedling recruitment [7][8][9], providing nutrients that increase primary production [10] and, overall, boosting ecosystem functioning [11]. In short, the role of snags and other CWD as biological legacies that promote biodiversity, regeneration, and ecosystem functioning has been increasingly demonstrated by studies performed mostly in the last couple of decades.…”

“…The reasons for conducting SL are diverse, but are largely related either to the recovery of economic capital still available in the remaining wood soon after the disturbance, or to facilitate future restoration or reforestation [19,20]. Nonetheless, this management action has been sharply criticized in the last two decades, and a growing number of studies have showed that salvage logging may seriously compromise ecosystem regeneration [3][4][5][6][7][8][9][10][11][12][13][14][15]21,22]. It is becoming increasingly clear that the negative effect of SL is related to its impact on habitat structure and components, which is linked primarily to the amount of biomass removed and the simplification of habitat structure [9,10,12,23].…”

Postfire Burnt-Wood Management Affects Plant Damage by Ungulate Herbivores

“…Post-fire salvage logging (i.e., the felling and removal of the burnt tree trunks, often eliminating the remaining woody debris by chipping, mastication, fire, etc.) has historically been routinely and widely practiced by forest administrations around the world [1][2][3][4], particularly in the case of burnt conifer forests. However, there is currently an intense debate about the suitability of this approach [5][6][7][8].…”

“…A growing number of studies show that salvage logging may increase soil erosion, diminish the regeneration capacity due to seedling bank or resprout destruction, or reduce the biodiversity of plants and animals [1,3,6,8], among other processes. As a result, there are increasing calls for less aggressive post-fire intervention policies, associated with evidence that snags and decaying burnt wood are components of natural systems that promote ecosystem recovery and diversity [4,5,[9][10][11][12].…”