An age-independent basal area increment model for maritime pine trees in northwestern Spain

• Published in: Forest ecology and management 2002-03, Vol.157 (1), p.55-64
• Main Authors: Schröder, Jörg, Soalleiro, Roque Rodrı́guez, Alonso, Guillermo Vega
• Format: Article
• Language: English
• Subjects: Basal area increment; Biological and medical sciences; Dendrometry. Forest inventory; Forestry; Fundamental and applied biological sciences. Psychology; Growth modeling; Pinus pinaster; Pinus pinaster Ait; Simulation
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/S0378-1127(00)00657-5

An individual tree basal area increment model for pure stands of maritime pine ( Pinus pinaster Ait.) is presented. The data used to fit the model were collected from 67 temporary 0.05 ha plots installed in regularly stocked, even- and uneven-aged stands located in Galicia (northwestern Spain). Explanatory variables used to predict the basal area increment are breast-height diameter outside bark, a diameter-squared term, a distance-independent competition index, crown spread ratio, and effective soil depth. Age and site index are intentionally omitted to obtain generality for a wide range of even- and uneven-aged stand conditions. The resulting model explains more than 78% of the total growth variation, corresponds to current hypotheses about tree growth, and is expected to provide reliable site-specific predictions for most of the pure maritime pine stands found in the study area.