How will global change affect photosynthesis and carbon transfer of future forests?

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Because Canada holds 33% of the world's boreal conifer forests, the response of these forests to global change is of paramount ecological and economic importance. Changes in growth and productivity of these ecosystems will directly affect their economic value, their ability to sequester carbon as well as sustainable management practice or biofuel production. The phenology of the biosphere, indicated by e.g. the carbon uptake period, has already been altered by global change. There is evidence of an increased productivity of forests due to an increase in growing season length, but there are also indications of other physiological processes concurrently having negative effects on productivity. Large uncertainties remain on the impact of global change at the beginning and the end of the growing season, such as the effect of increased autumn and spring temperature on e.g. the regulation of photosynthetic carbon uptake and the cold hardening and dehardening in boreal conifers. This research program investigates the impact of global change on phenological processes, photosynthesis and carbon transfer patterns of future forests and trees. It specifically aims to determine the effect of increased temperature and elevated CO2 on the (i) regulation of the cold hardening process of boreal conifers and the development of freezing resistance in autumn as well as to understand the (ii) consequences for the dehardening process in spring. This program will reduce uncertainties on tree responses to a multitude (not single!) of global change factors and provide better understanding of the regulatory network underlying acclimational processes. In addition, the program will generate novel data that can be used for parameterization to improve large scale models and it will provide knowledge to the forest sector to adapt management practices to future climatic conditions.