Evaluation of the Complex Stand Simulation Model SORTIE-ND for Timber Supply Review in Sub-Boreal Forests of Northern BC

ABSTRACT

A sensitivity analysis was performed to evaluate general model dynamics and model predictions were compared to independent datasets from forests of northwestern BC. Estimated parameters from selected behaviours were systematically varied to better understand model dynamics. The model is evaluated in terms of its logic and conceptual structure to ensure realistic representations of forest stands. We provide graphic description and summary statistics on the ranges of accuracy and precision of individual tree and stand level predictions. We document the effects of different types of calibration with the intent of making model predictions better align with independent data. To resolve the parameterization and calibration issues around model development we will maintain two versions of parameter files that drive the model: a research parameter file based on parameterization of field data and a management parameter file that will undergo calibration based on comparing model predictions to independent data.