6533b85ffe1ef96bd12c195f

RESEARCH PRODUCT

The Relations between the Sulphur Forms and the Organic and Mineral Components in Soils Developed under Spruce Forests in the Mont Lozere (France)

subject

description

Mean interannual (1981–1985) hydrochemical input-output budgets indicate net gains of sulphur in forested and unforested watersheds (1150–1450m deviation range) of Mont Lozere (2). The values of the sulphur gains, ranging from 5 to 10 kg/ha/yr. according to the watersheds are underestimated, since dry deposition is not considered in the budgets (1). It is now well known (3,4) that sulphur accumulation in forest catchments is mediated physically by sulphate adsorption on mineral amorphous surfaces and microbially by incorporation of sulphur into soil organic matter. To get a better assessment of these processes, in order to foresee their long term effects upon the proton-budgets and biogeochemical functioning of the ecosystems, the forms of sulphur stored in soils were identified and quantified. Results concern the variability of total S content in soil horizons and soil profiles and the distribution of different S-species and their relations to organic and inorganic soil components. For that, spruce stands were selected.