An Andosol–Cambisol toposequence on granite in the Austrian Bohemian Massif

In Europe, non-allophanic Andosols are linked with Hercynian basic and metabasic rocks in smoothed highlands with a cool and humid climate. We describe an Andosol–Cambisol toposequence derived from Variscan coarse-grained granite in Northern Austria (Bohemian Massif), where Andosols have formed on plateaus and Cambisols on steep slopes. The climate is continental, cool and humid (mean annual temperature and rainfall: 5.4 °C and 914 mm), with a 100-day mean annual period of snow cover. The forest is dominated by beech and spruce trees. Both soils are rich in organic matter and strongly acidic, but the Andosol is more strongly weathered than the Cambisol. Below the 15-cm-thick litter in the Andosol, the 38-cm-thick AB-Bw solum is dark reddish brown to strong brown, has a large C content (9.0–4.4%), and meets all the requirements of an andic horizon. In these horizons, oxalate extractable iron content (1.6–2.8% Feo) represents 76–84% of free iron, and is much larger than Alo (0.8–1.5%). Both biotite and plagioclase are sources of Fe and Al. The formation of non-allophanic Andosol from granite was likely due to the combination of the following factors: cool and humid climate, large accumulation of organic matter, high infiltration rate, intense water percolation during spring thawing and significant content of weatherable minerals. As such conditions are not rare in European highlands, andic soils are probably more widespread in Europe than is currently thought.