Using geographical information systems (GIS) and large area databases to predict Yield Class: A study of Sitka spruce in Wales

Abstract

A geographic information system (GIS) is used to combine and analyse data from a variety of existing large area databases concerning tree growth, plantation management and the environmental characteristics of planted sites. Principal component analysis and regression techniques are employed to estimate a number of Yield Class models for Sitka spruce (Picea sitchensis (Bong). Carr.). The GIS is used to extrapolate results and generate maps of predicted yield for a large study area (the entirety of Wales). The resulting methodology produces well fitting models of timber yield which compare favourably with those reported in the literature while the GIS generated maps are readily compatible with those currently under construction by various UK forestry authorities in order to plan for a proposed increase in afforested land.