PROMOTING ACCESS TO AFRICAN RESEARCH

Southern Forests: a Journal of Forest Science

Log in or Register to get access to full text downloads.

Remember me or Register



DOWNLOAD FULL TEXT Open Access  DOWNLOAD FULL TEXT Subscription or Fee Access

Modelling dominant height growth in plantations of Pseudotsuga menziesii (Mirb.) Franco in Spain

Carlos A López-Sánchez, Juan G Álvarez-González, Ulises Diéguez-Aranda, Roque Rodríguez-Soalleiro

Abstract


A model for predicting dominant height growth and site index of Pseudotsuga menziesii (Mirb.) Franco in Spain was constructed. Data from stem analysis of 117 site trees were used. Four dynamic equations using the algebraic difference approach (ADA) and its generalisation (GADA), which have provided good results in previous studies, were evaluated. The model parameters were estimated with the base-age-invariant method of dummy variables, which considers both global (common to all sites) and local parameters (specific to each site). A GADA equation based on the Bertalanffy–Richards base model yielded the best results. The model provides polymorphic curves with multiple asymptotes. A base age of 20 years is proposed to reference site index.

Keywords: Bertalanffy–Richards model, Douglas fir, generalised algebraic difference approach, site quality




AJOL African Journals Online