Influence de l’amendement sur la composition et la dynamique du cortège floristique pour des peuplements situés sur sols acides

Soil conditioners are an effective tool for recapitalising fertility in acidic soils. Three experiments were conducted to quantify these effects on the diversity and dynamics of the floristic succession of the treated populations. The effect of browsing by the fauna was also assessed. The results show an enhancement in neutro-nitrophilous and heliophilous species that tend to be ubiquitous following application of amendments. This enrichment continues and has sometimes intensified 8 years after the treatment. In most cases, the species found prior to the amendment have not disappeared, but the abundance of acidiphilous species (e.g. Calluna vulgaris, Leucobryum glaucum) significantly decreased. The results of fencing in plots also underscore the strong pressure the fauna brings to bear on the biomass and the floristic composition. Considered in combination, these results provide a good illustration of the impact of amendments on the flora, which is often used as an indicator for variations in soil fertility.