Résumé :
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In the context of the general increase of cervid populations in France for twenty five years, it seems helpful for forest managers to have a tool to appreciate the diet value of forest habitats. This tool must be straightforward and should take into account the local ecological reality, as a lot of various environments are present in France. We have developped typologies of diet " facies ", based on readings of ground covers and browsing marks, according to a sampling that cover the range of ecological conditions and forest stands. The readings are adapted from Aldous methodology and include an accurate local flora description. By using multivariate analysis (variables : ground covers and differences from the uniform browsing, for each vegetal species), we obtain several types differing about : - the abundance of the diet supply - the composition of the diet supply - their use by cervids (preferred or underconsummed types) These types can be identified on the field thanks to a key of determination, using the ground cover of main species, and some selected thresholds. Each reading needs about 2 to 5 minutes and enables fast descriptions (60 to 100 readings per day per person including transfers). Simple coding sheets are associated to these typologies in order to know the global and specific amount of the diet supply. Several applications are possible : - during field sessions preliminary to forest management : this technique could enable a better assessment of cervid habitat use in forests, in the same way as soil, landscape, biodiversity, ... components. - in case of specific studies : about silvicultural techniques favourable to cervids, or the description of the living space of tracked animals, for instance.
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