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Les coupes sanitaires sont utilisées pour limiter l’impact sanitaire et économique des dépérissements forestiers. Dans cette revue de la littérature, nous avons examiné l’impact de ces coupes sur les services écosystémiques associés à la résilience des écosystèmes forestiers. Les coupes sanitaires affectent les communautés d’espèces forestières en réduisant la part des espèces de forêts fermées et en promouvant celles de milieux plus ouverts. Les essences dryades et à régénération obligatoire par graine sont plutôt défavorisées. Les caractéristiques physicochimiques des sols sont également affectées. Une meilleure prise ne compte des facteurs environnementaux dans les choix de gestion est recommandée. Messages clés Les coupes sanitaires s'additionnent à la sévérité des perturbations naturelles. Elles affectent négativement les espèces de milieux forestiers fermés au profit d'espèces de milieux forestiers ouverts. Elles peuvent induire une baisse de résilience dans les écosystèmes forestiers perturbés.

After affecting millions of hectares of pine forests in western Canada, the mountain pine beetle (MPB; Dendroctonous ponderosae Hopkins) is spreading out of its native range and into Canada's boreal forest. Impacts of outbreaks can be environmental, economic, and social, and an ecosystem services (ES) viewpoint provides a useful perspective for an integrated approach to assessing these impacts and may help to identify how possible management strategies could minimize these impacts. In this regards, a comprehensive overview of the ecosystem functions and socioeconomic factors that have been impacted by the current outbreaks in western Canada was carried out to facilitate a more general ES assessment. In addition to timber production, current MPB outbreaks have negative effects on provisioning services (water supply and food production) and aesthetic cultural services, while effects on regulating services (carbon and forest fire) are still in debate. Among the supporting services, nutrient cycling and aquatic habitat showed short- and long-term negative effects, while terrestrial habitat showed a mostly positive response. The overall impact on ES may be more severe if salvage logging is practiced as a post-MPB forest management strategy. The outcomes of this study may help to identify areas of greatest socioecological vulnerability to MPB and identify knowledge gaps and avenues for research to advance the ES framework for MPB outbreak management. [ABSTRACT FROM AUTHOR]

Natural disturbances in European production forests are undesired from an economic perspective but are important drivers of biodiversity. The removal of damaged timber to restore economic value is accompanied by negative effects on various species groups, particularly breeding bird communities, and can hinder natural regeneration. However, little is known about the effect of postdisturbance logging on bird assemblages in winter when temperatures are low and food resources are unpredictable. We conducted fixed-radius point counts of wintering birds in forest stands logged or unlogged after windthrows and in mature forest stands to test our predictions that bird species densities and abundances (i) are lower in postdisturbance logged stands and (ii) depend on the amount of natural regeneration, (iii) which differs between logged and unlogged stands. Our generalized linear mixed model did not support the expected differences in bird abundance or species densities between postdisturbance logged and unlogged stands but indicated that mature forest stands harbor the highest bird abundances and species densities. The number of regenerated coniferous trees significantly positively affected wintering bird abundances in both postdisturbance logged and unlogged stands. Hence, the number of coniferous trees appears to be a main predictor of wintering bird presence. [ABSTRACT FROM AUTHOR]

Fire is a significant agent for the development of boreal and hemiboreal forests, altering soil and light conditions, affecting seedbanks, and removing seed trees. Burned areas should be managed with care, as inappropriate techniques prolong the regeneration period and reduce the diversity and resilience of stands to disturbances. To study the effects of fire and postfire management on the successional changes in regeneration abundance, species composition and tree height sample plots were established in sandy pine forests in northwestern Estonia on areas burned 2 or 22 years ago. Five types of sample plots were established: (i) areas without fire damage, (ii) burned uncleared areas, (iii) burned forest areas cleared after forest fire, (iv) burned uncleared areas with live trees, and (v) burned uncleared areas with dead trees. Three main tree species common to hemiboreal forests were analyzed: Betula spp., Pinus sylvestris L., and Populus tremula L. Results showed that clearing burned areas after wildfire significantly reduced the abundance of regeneration compared with burned uncleared areas but favored height growth of P. sylvestris in later development. To regenerate and maintain mixed stands after wildfire, retaining some residual trees can facilitate regeneration compared with complete clearing, although a dense stand with live trees or a large amount of deadwood can hinder regeneration. [ABSTRACT FROM AUTHOR]

Empirical knowledge of long-term ecosystem response to single and compound disturbances is essential for predicting disturbance effects and identifying management practices to maintain productive capacity of managed and restored landscapes. We report on soil, foliar nutrition, and regeneration growth response to wildfire, clearcut harvesting, and postfire salvage logging, as well as undisturbed control stands within the first year following disturbance and 10-11 years after disturbance in trembling aspen - white spruce mixedwood forests near Lesser Slave Lake, north-central Alberta, Canada. The compound disturbance of salvage logging resulted in greater long-term impacts on forest floor properties than either wildfire or harvesting alone. Changes in forest floor properties such as carbon and nitrogen pools and cation exchange capacity under salvage logging have persisted for 10 years and exhibit a different recovery trajectory than fire or harvesting. Forest floor properties under harvesting, including depth, carbon content, pH, extractable ammonium, and extractable sulphur, were not different from the control condition 10 years after harvest. Effects on soil and foliar nutrition were not reflected in productivity (height and diameter) of regenerating vegetation. Our results show differences between short- and long-term responses to disturbance, among single natural and anthropogenic disturbances, and among single and compound disturbances. [ABSTRACT FROM AUTHOR]

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Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)