© 2006 Heron Publishing—Victoria, Canada
Climate warming and the risk of frost damage to boreal forest trees: identification of critical ecophysiological traits
Heikki Hänninen (1, 2)
1. Plant Ecophysiology and Climate Change Group (PECC), Plant Biology, Faculty of Biosciences, University of Helsinki, Finland / 2. Corresponding author (heikki.hanninen@helsinki.fi) / Received June 1, 2005; accepted September 3, 2005; published online April 3, 2006
Summary
According to a hypothesis presented in the mid-1980s, climate warming will, paradoxically, increase the risk of frost damage
to trees in the boreal and temperate zones. Dehardening and even growth onset may occur in trees during mild spells in winter
and early spring, resulting in damage during subsequent periods of frost. In the present study, ecophysiological traits critical
to the occurrence of frost damage in trees in the boreal zone were identified. Diagnostic computer simulations were performed
to examine why one simulation model of frost hardiness in an earlier study predicted heavy frost damage as a consequence of
climate warming, whereas another closely related model did not. The modeling comparison revealed that the response of ontogenetic
development to air temperature during quiescence is a critical factor determining the risk of frost damage. As the response
can be readily determined in growth-chamber experiments, the findings of the present study can be used to guide experimental
work on the environmental regulation of the annual cycle of frost hardiness in trees.
Keywords:
annual cycle, phenology, scenario analysis, simulation modeling, tree traits.
