Analysing the effects of local environment on the source-sink balance of Cecropia sciadophylla: a methodological approach based on model inversion

Letort , Heuret , Zalamea , Reffye , Nicolini

Context Functional-structural models (FSM) of tree growth have great potential in forestry, but their development, calibration and validation are hampered by the difficulty of collecting experimental data at organ scale for adult trees. Due to their simple architecture and morphological properties, "model plants" such as Cecropia sciadophylla are of great interest to validate new models and methodologies, since exhaustive descriptions of their plant structure and mass partitioning can be gathered. Aims Our objective was to develop a model-based approach to analysing the influence of environmental conditions on the dynamics of trophic competition within C. sciadophylla trees. Methods We defined an integrated environmental factor that includes meteorological medium-frequency variations and a relative index representing the local site conditions for each plant. This index is estimated based on model inversion of the GreenLab FSM using data from 11 trees for model calibration and 7 trees for model evaluation. Results The resulting model explained the dynamics of biomass allocation to different organs during the plant growth, according to the environmental pressure they experienced. Perspectives By linking the integrated environmental factor to a competition index, an extension of the model to the population level could be considered.

Mots clés: functional structural model; morphology; trophic competition

Mots clés: cecropia; model inversion

Domaines: Sylviculture, foresterie

Letort, Heuret, Zalamea, Reffye, Nicolini. Analysing the effects of local environment on the source-sink balance of Cecropia sciadophylla: a methodological approach based on model inversion. Annals of Forest Science, 2012, 69 (2), pp.167-180. ⟨10.1007/s13595-011-0131-x⟩. ⟨hal-00930702⟩