Dynamic top height models for several major forest tree species in Great Britain

Abstract

In this paper, we present new dynamic top height models for 10 major species in Great Britain. These models for pure, even-Aged stands replace the current, static top height-Age curves published in the 1980s, which are no longer reliable in the light of the new data that have been added over the past decades. We followed the generalized algebraic difference approach (GADA) to build the new models and specifically focused on models derived from the Hessfeld IV and Chapman-Richards height-Age base equations. We selected a multi-Asymptote and polymorphic GADA version of the Chapman-Richards equation for all the species, with the anamorphic functional form as a special case derived from the non-significance of one of the global parameters. The new models are dynamic, accurate and robust, which will permit unbiased yield predictions from current top height-dependent yield simulators in Great Britain.