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Auteur Kjell Andreassen |
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Models for integrating and identifying the effect of senescence on individual tree survival probability for Norway spruce / Jouni Siipilehto in Silva fennica, vol 55 n° 2 (April 2021)
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Titre : Models for integrating and identifying the effect of senescence on individual tree survival probability for Norway spruce Type de document : Article/Communication Auteurs : Jouni Siipilehto, Auteur ; Harri Mäkinen, Auteur ; Kjell Andreassen, Auteur ; Mikko Peltoniemi, Auteur Année de publication : 2021 Article en page(s) : n° 10496 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] âge du peuplement forestier
[Termes IGN] analyse comparative
[Termes IGN] dynamique de la végétation
[Termes IGN] Finlande
[Termes IGN] modèle de croissance végétale
[Termes IGN] modélisation de la forêt
[Termes IGN] mortalité
[Termes IGN] Norvège
[Termes IGN] Picea abies
[Vedettes matières IGN] ForesterieRésumé : (auteur) Ageing and competition reduce trees’ ability to capture resources, which predisposes them to death. In this study, the effect of senescence on the survival probability of Norway spruce (Picea abies (L.) Karst.) was analysed by fitting alternative survival probability models. Different model formulations were compared in the dataset, which comprised managed and unmanaged plots in long-term forest experiments in Finland and Norway, as well as old-growth stands in Finland. Stand total age ranged from 19 to 290 years. Two models were formulated without an age variable, such that the negative coefficient for the squared stem diameter described a decreasing survival probability for the largest trees. One of the models included stand age as a separate independent variable, and three models included an interaction term between stem diameter and stand age. According to the model including stand age and its interaction with stem diameter, the survival probability curves could intersect each other in stands with a similar structure but a different mean age. Models that did not include stand age underestimated the survival rate of the largest trees in the managed stands and overestimated their survival rate in the old-growth stands. Models that included stand age produced more plausible predictions, especially for the largest trees. The results supported the hypothesis that the stand age and senescence of trees decreases the survival probability of trees, and that the ageing effect improves survival probability models for Norway spruce. Numéro de notice : A2021-737 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.14214/sf.10496 Date de publication en ligne : 10/06/2021 En ligne : https://doi.org/10.14214/sf.10496 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98696
in Silva fennica > vol 55 n° 2 (April 2021) . - n° 10496[article]