Girdling increases branch capacity to rehydrate in Juniperus thurifera and drought hampers bimodal growth

Disentangling how forests respond to aridification in terms of carbon storage and use, including bimodal growth, is critical to forecast their mitigation potential. Bimodality, characteristic of Mediterranean trees, refers to the potential to produce a second growth peak after the dry summer, often...

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Detalles Bibliográficos
Autores: Camarero, Jesús Julio, Salomón, Roberto L., Gazol Burgos, Antonio, Valeriano, Cristina, Tamudo, Elisa, Rubio-Cuadrado, Álvaro, Colangelo, Michele
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2026
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/424753
Acceso en línea:http://hdl.handle.net/10261/424753
https://api.elsevier.com/content/abstract/scopus_id/105030594590
Access Level:acceso abierto
Palabra clave:Drought
Intra-annual wood density fluctuation
Juniperus thurifera
Non-structural carbohydrates
Point dendrometer
Descripción
Sumario:Disentangling how forests respond to aridification in terms of carbon storage and use, including bimodal growth, is critical to forecast their mitigation potential. Bimodality, characteristic of Mediterranean trees, refers to the potential to produce a second growth peak after the dry summer, often accompanied by intra-annual wood density fluctuations (IADF). To induce IADF formation, we performed a girdling experiment on Spanish juniper (Juniperus thurifera) branches in a semi-arid site, and monitored changes in branch diameter, and measured non-structural carbohydrate (NSC) concentrations in sapwood and leaves. IADFs were formed in response to wet conditions in late summer in girdled and non-girdled branches. After girdling, the extraordinarily dry 2022 growing season hampered branch radial increment and IADF production. Girdled branches swelled more than control branches after rain pulses. This suggests girdled branches were osmotically more active. Girdled branches presented higher starch leaf concentrations, suggesting that osmolytes could proceed from starch hydrolysis upstream. Girdling did neither trigger bimodal growth nor IADF formation during a very dry year.