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The local occurrence of red subsoils on the Late Pleistocene sandy deposits of the Northern European lowlands invites investigation into the formation and paleoenvironmental significance of these soils. According to the World Reference Base for Soil Resources (WRB), these soils are classified as Rhodic Brunic Arenosols or Chromic Brunic Arenosols; however, because of their unclear origins, these soils are still not considered in the German Guidelines for Soil Mapping. We aim to characterize the genesis of these rubified soils by combining pedological findings with chemical analyses and micromorphological studies at four sites in southeastern Brandenburg, Germany. Our novel analytical approach differentiates pedogenic iron (hydr-)oxides using a combination of Fourier transform infrared-multiple internal reflection (FTIR-MIR) spectroscopy and sequential sample heating (from 21 °C to 100 °C, 250 °C, 500 °C, and 950 °C). Together with a comparison of synthetic iron (hydr-)oxides, the results of this analytical approach demonstrate that the mineralogy of these Rhodic Brunic Arenosols and Chromic Brunic Arenosols are characterized mainly by hematite; some goethite and minor amounts of maghemite are also present. Our results confirm recent findings from Jankowski (2013) that rubification is not primarily a relict process in Central European soils; consequently, the German Guidelines for Soil Mapping require revision. The high total iron contents in the rubified soils suggest strongly that the iron is allochthonous in origin, emphasizing the importance of lateral inputs of iron compounds in the genesis of these soils. This finding is highly consistent with the ‘translocation catena’ concept ( Sommer and Schlichting, 1997 ); i.e., the Rhodic Brunic Arenosols and Chromic Brunic Arenosols studied here formed due to inputs of allochthonous compounds. These rubified soils examined in this study share some genetic features with other soils described from Central Europe, such as the ‘Lockerbraunerden’ or the ‘Ockererden’. Further research should focus on these commonalities and compare the genetic pathways of such soils to support the argument that these soils should be considered in a separate soil class in the German Guidelines for Soil Mapping.

Inland salt meadows are particularly valuable ecosystems, because they support a variety of salt-adapted species (halophytes). They can be found throughout Europe; including the peatlands of the glacial lowlands in northeast Germany. These German ecosystems have been seriously damaged through drainage. To assess and ultimately limit the damages, temporal monitoring of soil salinity is essential, which can be conducted by geoelectrical techniques that measure the soil electrical conductivity. However, there is limited knowledge on how to interpret electrical conductivity surveys of peaty salt meadows. In this study, temporal and spatial monitoring of dissolved salts was conducted in saline peatland soils using different geoelectrical techniques at different scales (1D: conductivity probe, 2D: conductivity cross-sections). Cores and soil samples were taken to validate the geoelectrical surveys. Although the influence of peat on bulk conductivity is large, the seasonal dynamics of dissolved salts within the soil profile could be monitored by repeated geoelectrical measurements. A close correlation is observed between conductivity (~ salinity) at different depths and temperature, precipitation and corresponding groundwater level. The conductivity distribution between top- and subsoil during the growing season reflected the leaching of dissolved salts by precipitation and the capillary rise of dissolved salts by increasing temperature (~ evaporation). Groundwater levels below 0.38 cm resulted in very low conductivities in the topsoil, which is presumably due to limited soil moisture and thus precipitation of salts. Therefore, to prevent the disappearance of dissolved salts from the rooting zone, which are essential for the halophytes, groundwater levels should be adjusted to maintain depths of between 20 and 35 cm. Lower groundwater levels will lead to the loss of dissolved salts from the rooting zone and higher levels to increasing dilution with fresh rainwater. The easy-to-handle conductivity probe is an appropriate tool for salinity monitoring. Using this probe with regressions adjusted for sandy and organic substrates (peat and organic gyttja) additional influences on bulk conductivity (e.g. cation exchange capacity, water content) can be compensated for and the correlation between salinity and electrical conductivity is high.

According to the German Soil Taxonomy, the formation of cemented horizons in Podzols is restricted to the precipitation of iron oxides. However, in iron-poor sandy substrates, also illuviation of only organic compounds can form cemented horizons with penetration resistances of up to 14 kg cm−2. We present a reproducible field test for classifying pedogenic cementation in Podzols and suggest considering cemented horizons (Bmh and Bhm) in the upcoming edition of the Guidelines for Soil Mapping.

Agriculturally used peatlands are prone to carbon loss and soil degradation. The intensity of the underlying processes differs locally with respect to land management practices as well as hydro-geomorphic setting and soil conditions. A reliable assessment of the site specific vulnerability to carbon loss is important information to enable effective and precise agricultural and environmental policy. In the frame of a research project to derive an updated map of peatland soils for the Federal State of Brandenburg, located in the North-East of Germany, 7725 soil investigations on peatland sites were carried out thereof 3729 were suitable for peatland subsidence analyses. These data, together with extensive legacy data consisting of approx. 246,650 soil profiles, allow for robust carbon loss estimations based on peatland subsidence records. Observed carbon losses amount to 0.234 kg/m 2 ∗ yr at (presently) uncultivated sites, 0.562 kg/m 2 ∗ yr for grassland and 0.645 kg/m 2 ∗ yr for arable land. These figures agree well with recently published data for similar landscapes and land management practices. Taking into account additional information on the initial peat thickness, the type of underlying substrate and the presence or absence of a mineral top layer, a robust site-specific assessment of vulnerability to carbon loss for agriculturally used peatlands has been done. It is shown that > 50% of agriculturally used peatlands in Brandenburg are characterized by medium or high vulnerability to carbon loss.

This study outlines the opportunities for geoarchaeological research in active opencast lignite mines in southern Brandenburg (Germany). Studies on extensive outcrops that address both archaeology and soil geomorphology, combined with a geographical information system (GIS) approach, provide unique insights into human-induced environmental changes in Lower Lusatia and generally improve our understanding of landscape dynamics. We present the most recent results from three case studies and review important findings from the last several years. Studies conducted in opencast mines of Cottbus-Nord and Janschwalde focus on (i) Late Quaternary geomorphodynamics and soil development and (ii) past land use and the legacy of agriculture and woodland use. Our results are similar to those in other regions in Central Europe, but we also observe regional differences caused by the local setting, e.g. intensification of soil erosion coinciding with the expansion of farming of cultivated lands in the Slavic Middle Ages. Our research reveals the largest archaeologically investigated area of historical charcoal production in the Northern European Lowland (NEL). We are clearly only beginning to understand the massive dimensions of charcoal production in the region.