Comparison of Forest Models at the Leaf and Canopy Scale

Abstract

To estimate the uncertainty range in the prediction of long-term dynamics of forest stands in a changing climate a comparison of model results was undertaken within the framework of the EU-project LTEEF. As model predictions varied considerably, the dynamics were investigated on the commonly modelled smaller scales of the leaf and the canopy. The simulation experiment was carried out for a Pinus pinaster Ait. stand at Bray with six different models. Also on these scales differences in model outputs were considerable, especially temperature response curves of photosynthesis. To trace sensitivity to climate change across scales relative indices for different scenarios were defined and calculated. It was shown that differences at the leaf scale transform for most models similarly to higher scales. It is proposed that incorporation of existing detailed knowledge on the leaf level consistently into a range of forest growth models, would enhance the reliability of predicted long-term dynamics in a changing climate.