Plot, stand, and covertype aggregation effects on projections with an individual tree based stand growth model.

Abstract

A distance-independent individual-tree-based growth model (MFPS) was used to project changes in stand structure on aspen, red pine, and jack pine covertypes in northern Minnesota for 37 years. Individual .058 ha plot projections, projections of plots aggregated within stands, and projections of plots aggregated within covertypes were compared to each other and to observed plot conditions. Actual plot observations were available for up to 17 years. Individaul plot, stand, and covertype aggregations produced very similar projections in terms of number of trees, average diameter, basal area, and biomass. Plot by plot projections were most accurate in comparison with observed conditions, followed by stand and then covertype aggregations. Differences from actual values and among projections generally increased with longer projections.