Résumé
Direct and semi-direct estimations of leaf area (LA) and leaf area index
(LAI) are scarce in dense tropical forests despite the importance of such
measurements to calibrate remote-sensing products, forest dynamics and
biogeochemical models (e.g. Dynamic Global Vegetation Models). Extensive
and destructive sampling of 61 trees belonging to 13 species spanning all
diameter and wood density classes was performed in the semi-deciduous
forest of southeastern Cameroon. For each tree, all leaves were weighed,
counted for a subsample of branches and LA measured for 10-50 leaves.
Allometric models were calibrated to allow semi-direct estimation at tree-
and stand-levels, based on forest inventory data (R²=0.7, bias=21.2%,
error=39.5%), also on novel tree metrics allowed by remote-sensing like
airborne light detection and ranging (R²=0.63, bias=35.1%, error=58.73).
Using twenty-one 1-ha forest inventory plots, stand-level estimations of
LAI spanned from 4.42-13.99. Models produced at stand-level estimation may
be considerably useful to climate-vegetation modelling and remote-sensing
communities.