1. Risto Sievänen 1 Eero Nikinmaa 2 Christian Messier 3 Jari Perttunen 1 1. The Finnish Forest Research Institute 2. Dept. of Forest Ecology, University of Helsinki 3. GREF, Université du Québec à Montréal Modeling the effects of metabolism and 3D crown structure on tree growth

2. CONTENTS Functional-structural tree models The Model LIGNUM Some Applications Conclusions

3. Process-based models Vegetative and reproductive growth Photosynthesis, respiration and carbon allocation Mineral metabolism, especially nitrogen metabolism Growth regulations Intra-tree transfer of metabolites

4. Morphological models L-systems Other mathematical presentations of branching systems

5. Here comes a pictrue from Algorithmic beauty of plants

6. Process-based model  Morphological model = Functional-structural model (FSM)

8. Features of a FSM A basic unit is used for presentation of both architecture and functioning (metabolism) These units are combined to form different organisational levels Local control

9. LIGNUM: General features Simple structural units account for both structure and functioning of trees. Annual net production is used to new growth. Pipe model and functional balance for partitioning of growth. Time step one growth period (one year).

10. LIGNUM: The structure

11. LIGNUM: Tree Segment for deciduous trees

12. LIGNUM: Releasing suppressed buds

13. LIGNUM: Carbon balance

14. LIGNUM: Length of new segments

15. LIGNUM: New buds

16. LIGNUM: The Radiation Submodel (self shading) Shading Shaded

17. Scots pine Scots pine and Jack pine the first two tree species implemented. Proved the modeling approach feasible. Modeled (published) trees 10 years old.

18. Sugar maple " Study the survival and growth of sugar maple saplings in forest gaps. " Cutting guidelines for natural regeneration of sugar maple: Size of the canopy openings Frequency of cuttings

19. Three 5 year old saplings in St-Hilaire Closed GapReleased ZenithOpen Gap L = 1.37m L = 2.43m L = 2.84m

20. Gliricidia sepium " Nitrogen fixing tropical tree species used in agroforestry. " Study the optimal management (frequency of cuttings).

21. Mountain birch Structural analysis of mountain birch Based on detailed measurements done in Finnish Lapland

22. Analysis of Sapflow

23. Concluding Remarks To be added

24. www.metla.fi/projects/lignum