A unique data base in France for individual tree volumes and biomass for use in all-purpose models of wood energy

A base for volume and biomass data of the aerial woody compartments of individual trees was constituted under the ANR EMERGE (French acronym for 'designing models for a robust, all-purpose estimation of wood energy') project by seven bodies involved in forest research and management in France (ONF, INRA, Cemagref, IFN, FCBA, CNPF and CIRAD) so as to come up with a robust model of woody resources in forests. These measurements, taken for various logging diameters, sometimes down to the slenderest branches, have been performed since the beginning of the 20. century forming a unique data base in France. The data cover a broad range of age groups, sizes, species, stand structures and environmental factors (soil, climate). Of particular interest is the distribution of the available data in relation to French resources as estimated in the National Forest Inventory so as to use sampling campaigns to collect missing information under the EMERGE project. Another significant feature is the potential for designing robust, all-purpose models of volumes and biomass for various logging diameters depending on species, stage of development, geographic gradients, variations in silvicultural practises and possible effect of date of measurement. (authors)