Salvage logging effects on regulating and supporting ecosystem services — a systematic map

Abstract

Wildfires, insect outbreaks, and windstorms are increasingly common forest disturbances. Post-disturbance management often involves salvage logging, i.e., the felling and removal of the affected trees; however, this practice may represent an additional disturbance with effects on ecosystem processes and services. We developed a systematic map to provide an overview of the primary studies on this topic and created a database with information on the characteristics of the retrieved publications, including information on stands, disturbance, intervention, measured outcomes, and study design. Of 4341 retrieved publications, 90 were retained in the systematic map. These publications represented 49 studies, predominantly from North America and Europe. Salvage logging after wildfire was addressed more frequently than after insect outbreaks or windstorms. Most studies addressed logging after a single disturbance event, and replication of salvaged stands rarely exceeded 10. The most frequent response variables were tree regeneration, ground cover, and deadwood characteristics. This document aims to help managers find the most relevant primary studies on the ecological effects of salvage logging. It also aims to identify and discuss clusters and gaps in the body of evidence, relevant for scientists who aim to synthesize previous work or identify questions for future studies.

Overlapping Bark Beetle Outbreaks, Salvage Logging and Wildfire Restructure a Lodgepole Pine Ecosystem

“…However, as observed here and elsewhere, logging increases surface fuel loads [34,63], and in the event of a post-harvest wildfire, has the potential to exacerbate fire behavior and effects [64]. Salvage harvesting is controversial where it fails to meet intended objectives [60,65] and at Church's Park there was potential that logging in conjunction with the overlapping beetle and wildfire disturbances would have unintended negative consequences for biodiversity, ecosystem function and delivery of ecosystem services [61]. Regional concerns for management of federal forest lands include regenerating well-stocked forests, retaining native plant diversity and cover, maintaining soil and ecosystem productivity and protecting clean water supply.…”

“…Salvage logging is prescribed to address numerous objectives [60,61] and in response to recent insect outbreaks it has been used to reduce canopy fuels and crown fire potential, capture the value of dead timber, regenerate forests, protect infrastructure and humans from falling trees, and facilitate fire suppression [62]. However, as observed here and elsewhere, logging increases surface fuel loads [34,63], and in the event of a post-harvest wildfire, has the potential to exacerbate fire behavior and effects [64].…”

Salvage logging in the world’s forests: Interactions between natural disturbance and logging need recognition

“…Both types of interaction can show nonlinear behaviour relative to the intensity or severity of any of the disturbances (Peters et al, ). We argue that all these mechanisms likely operate when natural disturbance leaves behind dead trees that are subsequently harvested, as salvage logging generally occurs within the first two years after natural disturbance to avoid the deterioration of the wood (Leverkus et al, ). However, despite intense and ongoing public, academic, and political controversy surrounding salvage logging (Beschta et al, ; DellaSala et al, ; Donato et al; Leverkus, Jaramillo‐López, Brower, Lindenmayer, & Williams, ; Lindenmayer et al, ; Müller et al, ; Schiermeier, ; Thorn et al, ) and numerous studies aiming to assess its ecological consequences (reviewed in Leverkus et al, ; Thorn et al, ), explicit consideration of interactions between salvage logging and the preceding natural disturbance has mostly been neglected in empirical studies.…”

“…We argue that all these mechanisms likely operate when natural disturbance leaves behind dead trees that are subsequently harvested, as salvage logging generally occurs within the first two years after natural disturbance to avoid the deterioration of the wood (Leverkus et al, ). However, despite intense and ongoing public, academic, and political controversy surrounding salvage logging (Beschta et al, ; DellaSala et al, ; Donato et al; Leverkus, Jaramillo‐López, Brower, Lindenmayer, & Williams, ; Lindenmayer et al, ; Müller et al, ; Schiermeier, ; Thorn et al, ) and numerous studies aiming to assess its ecological consequences (reviewed in Leverkus et al, ; Thorn et al, ), explicit consideration of interactions between salvage logging and the preceding natural disturbance has mostly been neglected in empirical studies. As a result, to be able to understand the outcomes of salvage logging and mitigate its negative effects, there is a need to place its ecological effects within the framework of disturbance theory (e.g., Didham et al, ; Buma, ; Foster et al, ), with special focus on disturbance interactions and on the mechanisms through which such interactions may occur.…”

“…By applying the concepts of interaction modifications, interaction chains, and nonlinear effects (Foster et al, ), we aim to disaggregate the mechanisms driving ecological interactions related to salvage logging. We use data from a systematic literature review on salvage logging (Leverkus et al, ) to explore the extent to which interactions have been addressed to date. Our paper is organised in four sections, comprising (1) Interaction modifications, (2) Interaction chains, (3) Nonlinear behaviour, and (4) Recommendations for policy and practice.…”