A non-linear hierarchical mixed model to describe tree height growth

Berlin

Springer

2006

S. 281-289

4 Abb., 3 Tab., 21 Lit. Ang.

Artikel aus einer ZeitschriftUnselbständiges Werk

200136565

European Journal of Forest Research 2006, 125(3), S. 281-289

A non-linear hierarchical mixed model approach is used to describe height growth of Norway spruce from longitudinal measurements. The parameter variation in the model was divided into unknown random effects, fixed effects and covariate-dependent effects in order to model tree height growth. The values for fixed effect parameters and the variance-covariance matrix of random effects were estimated. Covariates could only explain up to 10% of parameter variability. Height curves were calibrated by means of BLUPs for the unknown random effects using prior height measurements and evaluated using a separate dataset. The resulting curves had a small error variance and plausible shapes.