Comparison and significance of annual hydrochemical budgets in three small granitic catchments with contrasting vegetation (Mont-Lozere, France)

Chemical budgets are presented for three small granitic catchments in Southeastern France, with contrasting vegetation type: beech coppice; spruce forest; and grassland. The results show a small net loss of cations, and a large accumulation of sulphur in the soil, which acts as an additional proton sink. Significantly higher weathering rates are observed for the conifer catchment. Clearfelling of the spruce forest, late in the monitoring programme, increased net cation and nitrate losses. The importance of dry atmospheric deposition in the input-output budget, particularly for forests, is highlighted.