Burn severity modifies the impact of salvage logging on post-wildfire natural regeneration of Douglas-fir in interior British Columbia

1. Exacerbated by climate change, wildfires in British Columbia, Canada, have increased in extent and severity, impacting forests, including commercially valuable species like interior Douglas-fir (Pseudotsuga menziesii var. glauca). Post-wildfire salvage logging aims to mitigate financial losses an...

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Detalles Bibliográficos
Autores: McAulay, Julie, Querejeta Mercader, José Ignacio, Eskelson, Bianca N.I., Daniels, Lori D., Ewen, Stephanie, Danyagri, Gabriel, Saunders, Sari C., Barbeito, Ignacio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:dnet:digitalcsic_::b3f2fed7f6762044692799ad7b8bdd04
Acceso en línea:http://hdl.handle.net/10261/430458
https://api.elsevier.com/content/abstract/scopus_id/105020860639
Access Level:acceso abierto
Palabra clave:Carbon stable isotopes
Early successional dynamics
Foliar nutrients
Nitrogen stable isotopes
Oxygen stable isotopes
Seedling growth
Water stress
Water-use efficiency
Descripción
Sumario:1. Exacerbated by climate change, wildfires in British Columbia, Canada, have increased in extent and severity, impacting forests, including commercially valuable species like interior Douglas-fir (Pseudotsuga menziesii var. glauca). Post-wildfire salvage logging aims to mitigate financial losses and accelerate regeneration, though its ecological impacts remain uncertain. 2. This study was conducted in the Alex Fraser Research Forest, where a 2017 wildfire burned approximately 1000 ha. Combined with 2023 seedling biomass and %N measurements, we used linear mixed-effects models to examine the physiological responses of regenerating interior Douglas-fir seedlings to burn severity and salvage logging, using carbon, nitrogen, and oxygen stable isotope analyses (δ<sup>13</sup>C, δ<sup>15</sup>N, and δ<sup>18</sup>O) to assess water-use efficiency (WUE<inf>i</inf>), photosynthesis, water stress, and nitrogen cycling post-disturbance. 3. Higher seedling biomass was found in high-severity, not-salvaged sites. Moderate-severity, not-salvaged sites had lower δ<sup>13</sup>C and δ<sup>18</sup>O values compared to high-severity (salvaged and not-salvaged) and moderates-severity, salvaged sites. Higher leaf %N was positively correlated with δ<sup>13</sup>C values across treatments, indicating enhanced water-use efficiency. 4. The statistically significant interactions between burn severity and salvage logging and their influence on seedling biomass, δ<sup>13</sup>C, and δ<sup>18</sup>O emphasize the key role of microclimatic conditions in post-fire recovery. In high-severity sites, salvage logging did not enhance seedling biomass, likely due to already sufficient light availability. In moderate-severity sites, salvage logging had small, positive effects on seedling biomass that were not statistically significant. Higher leaf nitrogen content appeared to boost WUE<inf>i</inf> across treatments. These findings support tailoring post-wildfire management to burn severity, with minimal intervention in high-severity areas and selective salvage in moderate-severity sites.