Modeling the Effect of Stand Characteristics on Oak Volume Increment in Poland Using Generalized Additive Models

Volume increment is one of the main concerns in forestry practice. The aim our study was to examine impact factors influencing periodic annual oak. To meet objective, we used measurement data from national forest inventory Poland 2005 2019 for oak-dominated stands. Our 1464 sample plots with dominant oak species (Quercus sessilis Ehrh. ex Schur and Quercus robur L.) measured within Poland. We developed models explaining dependence volume on stand characteristics using generalized additive model. model allows us analyze each variable’s effect dependent variable, all other variables fixed. documented age, height, basal area, relative spacing index (RSI) (PAIv) oaks PAIv decreased gradually as tree aged. density shown through its relationship area RSI. explained about 64.6% variance.