Canopy cover and species’ climatic niche shape Pinus sylvestris regeneration after drought-induced die-off

Drought-induced die-off alters canopy structure and understory microclimatic conditions, but its consequences for tree regeneration remain unclear. We assessed how canopy-driven microclimate filtering and climatic suitability influenced Pinus sylvestris regeneration across developmental stages (seed...

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Detalles Bibliográficos
Autores: Chowdhury, Faqrul Islam, Espelta, Josep Maria, Sánchez-Mejía, Teresa, Margalef-Marrase, Jordi, Jaime, Luciana, Lloret, Francisco
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2026
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:dnet:recercat____::db77887800ae0331a650a942bd3887f2
Acceso en línea:https://doi.org/10.1016/j.foreco.2025.123438
https://hdl.handle.net/10459.1/470067
Access Level:acceso abierto
Palabra clave:Canopy buffering
Drought legacy
Species niche
Regeneration density
Descripción
Sumario:Drought-induced die-off alters canopy structure and understory microclimatic conditions, but its consequences for tree regeneration remain unclear. We assessed how canopy-driven microclimate filtering and climatic suitability influenced Pinus sylvestris regeneration across developmental stages (seedlings, young saplings, and old saplings) following drought-induced die-off in forests across Catalonia (NE Spain). We analysed recruit densities with linear mixed models incorporating forest condition (die-off vs. control), canopy type (closed, defoliated, and open gaps), survey year (2013, 2017, and 2022), and climatic-niche metrics as fixed effects, while site and plot were considered as random effects. In closed habitats, die-off lowered both young and old saplings relative to controls. Defoliated habitats consistently failed to support regeneration across all stages, even in climatically favourable sites, likely due to impaired propagule supply. Open habitat enhanced seedling and sapling densities in die-off plots. Regarding the position in the climatic niche, old saplings persisted in closed habitats at climatically marginal sites, likely benefiting from canopy-mediated microclimate control. Canopy buffering also protected young saplings in closed habitats during the periods with strong interannual climate fluctuations. In open habitats, young and old saplings were sensitive to climatic position in species’ niche, with their densities declining with increasing distance to the optimum, core niche. Overall, seedlings’ density was higher near the climatic optimum in die-off plots than in controls. Also, nearly a decade after the drought, only young sapling densities increased in die-off plots, likely reflecting disturbance legacies and favourable climatic fluctuations. Our results highlight the silvicultural value of maintaining a mosaic of canopy structures, retaining open habitats in climatically optimal sites to enhance seedling establishment and progression, while preserving closed canopy refugia in marginal climatic sites to buffer climate extremes, thus, favouring saplings survival against increasing drought stress.