Modelling diameter class distribution with a second-order matrix model

Picard Nicolas, Bar-Hen Avner, Guédon Yann. 2003. Modelling diameter class distribution with a second-order matrix model. Forest Ecology and Management, 180 (1-3) : 389-400.

Résumé : Matrix models of forest dynamics rely on four hypotheses: independence hypothesis, Markov's hypothesis, Usher's hypothesis, and temporal homogeneity hypothesis. We investigate the consequences of relaxing Markov's hypothesis, allowing the state of the tree at time t to depend on its states at time t - 1 and t - 2. The methodology for building and testing the relevance of second-order matrix model is thus proposed. The derivation of second-order transition probabilities turns to be sensitive to the width of the diameter classes. A strategy for choosing diameter classes is proposed. A second-order matrix model is then built for a tropical rain-forest in French Guiana. A different behaviour is detected between small (dbh <=30 cm) and large trees, the smaller trees being more sensitive to their past history: small trees that have well grown have a tendency to grow well again, and small trees that have not grown tend to have a higher probability to die. The widths of the diameter classes that are selected are much less than the widths usually retained, that favour first-order selection.

Mots-clés Agrovoc : diamètre, croissance, modèle mathématique, dynamique des populations, forêt tropicale humide

Classification Agris : U10 - Informatique, mathématiques et statistiques
K10 - Production forestière

Auteurs et affiliations

• Picard Nicolas, CIRAD-FORET-FORETS NATURELLES (MLI)
• Bar-Hen Avner, Université Paul Cézanne (FRA)
• Guédon Yann, CIRAD-AMIS-AMAP (FRA)

Source : Cirad - Agritrop (https://agritrop.cirad.fr/523698/)

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