In uno studio  pubblicato di recente sulla rivista Geoscientific Model Development un gruppo di autori (fra questi, i ricercatori CMCC A. Collalti, S. Marconi, R. Valentini e M. Santini) hanno valutato le performance della nuova versione (v.5.1) del modello 3D-CMCC FEM nel simulare la produzione primaria (GPP, gross primary production) rispetto a dati ottenuti con tecniche di eddy covariance, per dieci siti forestali della rete europea FLUXNET.
Il modello 3D-CMCC FEM – Three Dimension Forest Ecosystem Model (Collalti et al., 2014) è un modello di processo, ibrido e dinamico per simulare accrescimento, allocazione del carbonio e dinamiche forestali. Il modello si basa sulla simulazione su scala giornaliera o mensile dei processi eco-fisiologici che governano la produzione primaria (GPP e NPP) e le dinamiche degli stock di carbonio in funzione della struttura del popolamento, dei pools di biomassa presenti, delle variabili pedologiche e climatiche.

L’abstract dell’articolo:

This study evaluates the performances of the new version (v.5.1) of 3D-CMCC Forest Ecosystem Model (FEM) in simulating gross primary production (GPP), against eddy covariance GPP data for ten FLUXNET forest sites across Europe. A new carbon allocation module, coupled with new both phenological and autotrophic respiration schemes, was implemented in this new version. Model ability in reproducing timing and magnitude of daily and monthly GPP fluctuations is validated at intra-annual and inter-annual scale, including extreme anomalous seasons. With the purpose to test the 3D-CMCC FEM applicability over Europe without a site-related calibration, the model has been deliberately parameterized with a single set of species-specific parameterizations for each forest ecosystem. The model consistently reproduces both in timing and in magnitude daily and monthly GPP variability across all sites, with the exception of the two Mediterranean sites. We find that 3D-CMCC FEM tends to better simulate the timing of inter-annual anomalies than their magnitude within measurements uncertainty. In six of eight sites where data were available the model well reproduces the 2003 summer drought event. Finally, for three sites we evaluate if a more accurate representation of forest structural characteristics (i.e. cohorts, forest layers) and species composition can improve model results. In two of the three sites results reveal that model slightly increases its performances, although, statistically speaking, not in a relevant way.

Leggi la versione integrale dell’articolo:
Collalti A., Marconi S., Ibrom A., Trotta C., Anav A., D’Andrea E., Matteucci G., Montagnani L., Gielen B., Mammarella I., Grünwald T., Knohl A., Valentini R., Santini M.
Validation of 3D-CMCC Forest Ecosystem Model (v.5.1) against eddy covariance data for ten European forest sites
2015, Geoscientific Model Development, 8, 6867-6929, DOI: 10.5194/gmdd-8-6867-2015