Properties, dynamics and association of soils on high elevations of the Bavarian Forest (Germany) as illustrated by a toposequence on gneiss debris

Abstract

The soils were surveyed, described and examined at a remote forested high-elevation site of the Bavarian Forest (Germany). They derive from periglacial gneiss debris consisting of an upper, loose stratum and an indurated zone below. The different hydraulic conductivity of both layers has important effects on the dynamics of water and nutrient elements, and thus on soil development. At the summit flat Hochlagen-Podsole (Fragiorthods and Fragiaquods according to US taxonomy) occur, while on the slope Braunerde-Podsole and Podsol-Braunerden (i.e. Fragiorthods and Fragiumbrepts) prevail. All these high-elevation soils are extremely rich in humus. They have a sandy loam to loamy sand texture, and the rock fragments make up 40–75 percent by volume. The low content of total Mg and total Ca is mainly explained by the poor parent materials. Furthermore, the effective cation exchange capacity (CEC e) of these acid soils is very low, and the base saturation varies around 15 IE% in the mineral soil. The poor Mg supply of these soils is probably worsened by a man-made increase of atmospheric S and N deposits which favour the acidification of these soils. Thus the widespread forest decline at the high elevations of the Bavarian Forest may be partly attributed to man.