Assessing impact of projected future climate on tree species growth and yield: development of an evaluation strategy

Abstract

Quantifying the impact of climate change on forest tree species growth and yield is required by all forest planners. Forest planners, who know which tree species have the growth characteristics to compete in a future climate, will be better able to design stand prescriptions tailored to promote these species. A method to acquire this understanding has been developed by implementing a forest gap model to predict ecological succession of Acadian Forest tree species over an 80-year time horizon for two climate scenarios (2010-2090), i.e., a current climate with average temperature and precipitation from the 1971-2000 normal period, and a future climate with time-varying temperature and precipitation projected with the Canadian Coupled Global Climate Model (CCGCM3), assuming an A2 emission scenario (Nakicenovic et al. 2000, IPCC Special report on emission scenarios). From these two simulations, time-dependent stand-yield multipliers are developed for individual tree species by calculating the proportional difference between the two scenarios. In principle, these multipliers can then be used to update inventory-based growth and yield curves to assess the impact of future climate on existing forest tree species and future regional wood supply characteristics. Results from this work indicate that for a CCGCM3-projected warmer climate pine (Pinus spp.), red maple (Acer rubra), American beech (Fagus grandifolia), yellow birch (Betula alleghaniensis), and white ash (Fraxinus americana) are likely to respond positively, whereas cold-hardy species such as white and black spruce (Picea spp.), balsam fir (Abies balasmea), larch (Larix laricina), and white birch (Betula papyrifera) are projected to respond negatively.