Quantitative aspects of carbonate leaching of soils with differing ages and climates

Carbonate leaching rates in several soils in Switzerland and in the Lake Constance region were calculated and related to landscape development. The leached depth of the soil, the carbonate content and the soil density profile are sensitive to soil age. A first database of carbonate leaching and its relationship to soil age is presented. A simple relationship between the amount of precipitation and carbonate losses was found. Water draining from calcareous soils from subarctic to temperate areas was usually close to equilibrium with calcite and dolomite. Thus, the annual amount of rainfall and consequently the percolation are the most important factors in carbonate leaching. The influence of temperature is comparatively low. Carbonate dissolution rates amounted to approximately 1.7–3.0 mol m−2 year−1 if they are referred (normalised) to 1000 mm soil water fluxes. Soils on coarse parent material may have slightly lower carbonate dissolution rates in the order of approximately 1.7–2.2 mol m−2 year−1 (normalised to a 1000 mm output), while other sites with smaller grain sizes had slightly higher dissolution rates (2.2–3.0 mol m−2 year−1).