Modelling the response of tree growth to temperature and CO2 elevation as related to the fertility and current temperature sum of a site

The simulations for Scots pine, Norway spruce and silver birch showed that the RSEv transfer functions worked logically in combination with the statistical growth and yield model, and that the results were logical with respect to the differences in productivity between sites and locations. However, the impact of location, as implied by current temperature sum, clearly had larger impact on growth reaction to climate change than did the variation between the site types. Regarding regional variations in current thermal conditions, the simulations of productivity under climate change were well in line with previous predictions; i.e. stem volume growth was enhanced more in northern than in southern Finland, because current temperatures have a greater limiting effect on growth in the north.