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Pourquoi et où les arbres adultes meurent dans une jeune forêt tempérée? Le rôle du voisinage

2009; Springer Science+Business Media; Volume: 66; Issue: 1 Linguagem: Inglês

10.1051/forest

1297-966X

José Miguel Olano, Nere Amaia Laskurain, Adrián Escudero, Marcelino de la Cruz,

Forest Management and Policy

• The density and identity of tree neighbourhood is a key factor to explain tree mortality in forests, especially during the stem exclusion phase. • To understand this process, we built a logistic model for mortality in a spatially explicit context, including tree and neighbourhood predictors. Additionally, we used this model to build mortality risk frequency distributions. Finally, we tested this model against a random mortality model to predict the spatial pattern of the forest. • Annual mortality rate was high for pedunculate oak (Quercus robur, 6.99%), moderate for birch (Betula celtiberica, 2.19%) and Pyrenean oak (Q. pyrenaica, 1.58%) and low for beech (Fagus sylvatica, 0.26%). Mortality risk models for pedunculate oak and birch included stem diameter, tree height, canopy position and neighbourhood. Mortality was affected by the specific nature of the neighbourhood showing a clear competitive hierarchy: beech > pedunculate oak > birch. Models based on random mortality and logistic regression model were able to predict the spatial pattern of survivors although logistic regression predictions were more accurate. • Our study highlights how simple models such as the random mortality one may obscure much more complex spatial interactions.