Annual cycle

Plants in the boreal zone have a clear annual rhythm.

The dormancy period in winter is followed by the onset of development and growth in spring. Growth, reproduction and largely photosynthesis occur during the active period, and these functions fall into dormancy in the autumn (Fig. 1). Timing of individual phenological events such as bud burst have been studied widely and for a long time (Linkosalo et al. 2008). Phenological events can be momentary such as bud burst or the opening of catkins (Sarvas 1972) or it can be continuous such as growth.

We have studied and quantified the annual cycle of photosynthesis (Suni et al. 2003, Mäkelä et al. 2004), organ growth and carbon allocation (Schiestl-Aalto et al. 2015) and the storage of non-structural carbon compounds in trees (Schielst-Aalto et al. 2019). The results of these studies have implications on the interactions between phenology and climate change. They also contribute to the discussion of source-sink interactions in growth.

This text was from Schiestl-Aalto (2017) Modelling intra- and inter-annual growth dynamics of Scots pine in the whole-tree carbon framework, Academic dissertation.


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