Evaluation of 11 terrestrial carbon-nitrogen cycle models against observations from two temperate Free-Air CO2 Enrichment studies.
Bottom Line: Nonetheless, many models showed qualitative agreement with observed component processes.The results suggest that improved representation of above-ground-below-ground interactions and better constraints on plant stoichiometry are important for a predictive understanding of eCO2 effects.Improved accuracy of soil organic matter inventories is pivotal to reduce uncertainty in the observed C-N budgets.
Affiliation: Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, D-07745, Jena, Germany.Show MeSH
Mentions: Observed ambient NPP and inferred fNup at Duke FACE were both slightly larger than at ORNL FACE (Figs3a,b), implying that the whole-plant NUE was similar between the sites (Fig.4) at 121 ± 2 g C g−1 N in the ambient plots (1997–2005 mean) for Duke FACE and 129 ± 13 g C g−1 N at ORNL. This similarity between sites is in contrast with an earlier study (Finzi et al., 2007), because the corrections in biomass estimates by McCarthy et al. (2010) resulted in a downward adjustment in the estimate of NUE at Duke Forest.
Affiliation: Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, D-07745, Jena, Germany.