1. with contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Sebastiaan Luyssaert
with contributions of 40+ research groups

2. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Introduction
Forest play an important role in the global C-cycle
Since 1970 ongoing effort to estimate production and respiration
Considerable uncertainties remain
Assembled a comprehensive global database
Sebastiaan Luyssaert and contributions of 40+ research groups

3. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Objectives
Explain some important feature of the database
Identify data gaps
Present relationships GPP, NPP, NEP, Ra, Rh and Re
Present CO2-budgets per biome
Sebastiaan Luyssaert and contributions of 40+ research groups

4. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
The database
Consistent NPP data
Consistent uncertainty
Ancillary information
Sebastiaan Luyssaert and contributions of 40+ research groups

5. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
The database
Consistent NPP data
Consistent uncertainty
Ancillary information
Expert judgement accounting for :
Applied methodology
Number of observations
Sebastiaan Luyssaert and contributions of 40+ research groups

6. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
The database
Consistent NPP data
Consistent uncertainty
Ancillary information
Coordinates, elevation, climatic region, growth form, management, tree species
Observed MAT, APS, LAI, age, height, BA, diameter, density, biomass
Monthly temperature, precipitation, rainy days, cloud cover data CRU
Modelled radiation components, air humidity, N-deposition, soil composition
NDVI
Sebastiaan Luyssaert and contributions of 40+ research groups

7. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Data
2000+ flux observations
380 sites
130 GPP, Re & NEP
250 NPP
130 Rh & Rs
35 Ra
Sebastiaan Luyssaert and contributions of 40+ research groups

8. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Data gaps
For GPP, NPP, NEP & Re need:
- Boreal ecosystems
- Tropical ecosystems
Sebastiaan Luyssaert and contributions of 40+ research groups

9. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Data gaps
For Ra & Rh need:
- All biomes except temperate humid
Sebastiaan Luyssaert and contributions of 40+ research groups

10. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of GPP
High GPP: warm wet
Low GPP: cold dry
Sebastiaan Luyssaert and contributions of 40+ research groups

11. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of GPP
Sebastiaan Luyssaert and contributions of 40+ research groups

12. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of GPP ?
Sebastiaan Luyssaert and contributions of 40+ research groups

13. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of GPP ?
Sebastiaan Luyssaert and contributions of 40+ research groups

14. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of GPP ?
Sebastiaan Luyssaert and contributions of 40+ research groups

15. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Global patterns in NPP
Sebastiaan Luyssaert and contributions of 40+ research groups

16. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NPP
Sebastiaan Luyssaert and contributions of 40+ research groups

17. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of GPP, NPP, Re and Rh
GPP ~ MAT, LAI, P
NPP ~ MAT, LAI, Rg
Re ~ MAT, LAI, P
Rh ~ MAT, ?
Sebastiaan Luyssaert and contributions of 40+ research groups

18. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NEP
GPP ~ MAT, LAI, P
NPP ~ MAT, LAI, P
Re ~ MAT, LAI, P
Rh ~ MAT, ?
NEP, ?
Unmanaged forests
Sebastiaan Luyssaert and contributions of 40+ research groups

19. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NEP
NEP ~ GPP
Sebastiaan Luyssaert and contributions of 40+ research groups

20. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NEP
NEP ~ GPP
Sebastiaan Luyssaert and contributions of 40+ research groups

21. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NEP
NEP ?
Age
Management
sink
source
Sebastiaan Luyssaert and contributions of 40+ research groups

22. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NPP/GPP
Ra, insuf. data
NPP/GPP
Sebastiaan Luyssaert and contributions of 40+ research groups

23. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NPP/GPP
NPP/GPP data
NPP/GPP max production
Sebastiaan Luyssaert and contributions of 40+ research groups

24. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NPP/GPP
NPP/GPP unmanaged
sites
Sebastiaan Luyssaert and contributions of 40+ research groups

25. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Dependence of NPP/GPP
Management > Temp
Sebastiaan Luyssaert and contributions of 40+ research groups

26. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Components of the CO2-balance
NPP = fNPP + wNPP + rNPP + mNPP
NEP = GPP - Re
NECB = NEP – non-CO2 losses – non-resp. CO2 losses + CO2 import/export
NBP = ∫∫ NECB
Sebastiaan Luyssaert and contributions of 40+ research groups

27. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Components of the CO2-balance
Benchmark for model validation
Closure problem
Sebastiaan Luyssaert and contributions of 40+ research groups

28. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Closure of the CO2-balance
Sebastiaan Luyssaert and contributions of 40+ research groups

29. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Components of the C-balance
Sebastiaan Luyssaert and contributions of 40+ research groups

30. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Global CO2-balance
Uncertainty when models follow the observations
Sebastiaan Luyssaert and contributions of 40+ research groups

31. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Conclusions
Database of field-observations available for model validation
Missing 2 out of 8 climate regions
Climate dependence of GPP, NPP, Re but not of NEP
NPP/GPP ratio is not 0.475
Substantial closure terms indicate shortcomings of field-observations
Sebastiaan Luyssaert and contributions of 40+ research groups

32. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
We want more...
Presentation Denis Lousteau: Management effects on the annual carbon balance of forests
Poster Ilaria Inglima: NPP drives Rh in forest ecosystems
Task force presentations Martin Jung: Comparison of models and observations
Sebastiaan Luyssaert and contributions of 40+ research groups

33. Sebastiaan Luyssaert and contributions of 40+ research groups
Relationships between GPP, NPP, NEP, Ra, Rh and Re in forest ecosystems
Contributors
I. Inglima, M. Jung, M. Reichstein, D. Papale, S. Piao, E.-D. Schulze, L. Wingate, G. Matteucci, M. Aubinet, C. Beer, C. Bernhofer, K.G. Black, D. Bonal, J.Chambers, P. Ciais, K.J. Davis, E.H. Delucia, A.J. Dolman, A. Don, B. Gielen, J. Grace, A. Granier, A. Grelle, T. Griffis, T. Grünwald, G. Guidolotti, P.J. Hanson, R. Harding, D. Hollinger, P. Kolari, B. Kruijt, W. Kutsch, F. Lagergren, T. Laurila, B. Law, G. Le Maire, A. Lindroth, F. Magnani, M. Marek, J. Mateus, M. Migliavacca, L. Misson, L. Montagnani, J. Moncrieff, E. Moors, J.W. Munger, E. Nikinmaa, D. Loustau, G. Pita, C. Rebmann, A.D. Richardson, O. Roupsard, N. Saigusa, M.J. Sanz, G. Seufert, L. Soerensen, J. Tang, R. Valentini, T. Vesala and I. Janssens
Funding
Belgian Research Foundation (FWO), CarboEurope-IP and Antwerp University
Sebastiaan Luyssaert and contributions of 40+ research groups