A micromorphological examination of two alpine soil chronosequences, Southern Norway

The micromorphological characteristics of young alpine soils (<230 years old) from two chronosequences in Norway are examined. Lenticular and alveolar microstructures, together with matrix granules, suggest that cryic processes are operative in subsurface (Ae, B, C) horizons. Organic matter accumulation, decomposition and incorporation are evident in surface (L, F, Ah) horizons, whereas hydration of biotite, and translocation of silt and fine-sand sized mineral particles, organic material and sesquioxides seem major processes in subsurface (Ae, B) horizons. Consideration of depth-related differences of quantitative micromorphological data has allowed assessment of the intensity of these pedogenic processes. Chronofunctions are constructed for each soil horizon from the quantitative data. This approach allows soil development at the two sites to be assessed in a temporal context. Steady-state conditions do not appear to be attained within the 230 years available for soil development at these sites.