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Purpose: Loess landscapes are highly susceptible to soil erosion, which affects soil stability and productivity. Erosion is non-linear in time and space and determines whether soils form or degrade. While the spatial variability of erosion is often assessed by either modelling or on-site measurements, temporal trends over decades to millennia are very often lacking. In this study, we determined long- and short-term erosion rates to trace the dynamics of loess deposits in south-western Poland. Materials and methods: We quantified long-term (millennial) erosion rates using cosmogenic (in situ 10Be) and short-term (decadal) rates with fallout radionuclides (239+240Pu). Erosion processes were studied in two slope-soil transects (12 soil pits) with variable erosion features. As a reference site, an undisturbed soil profile under natural forest was sampled. Results and discussion: The long-term erosion rates ranged between 0.44 and 0.85 t ha−1 year−1, whereas the short-term erosion rates varied from 1.2 to 10.9 t ha−1 year−1 and seem to be reliable. The short-term erosion rates are up to 10 times higher than the long-term rates. The soil erosion rates are quite consistent with the terrain relief, with erosion increasing in the steeper slope sections and decreasing in the lower parts of the slope, while still maintaining high values. Conclusions: Soil erosion rates have increased during the last few decades owing to agriculture intensification and probably climate change. The measured values lie far above tolerable erosion rates, and the soils were found to be strongly imbalanced and exhibit a drastic shallowing of the productive soils horizons. [ABSTRACT FROM AUTHOR]

• Erosion rates in loess–mantled soils ranged from 0.11 to 3.27 t ha−1 yr−1. • Loess mantles were significantly shallowed in the late Pleniglacial. • 10Be content depends on layered parent material, pedogenesis and phase of exposure. • Variation of 10Be hinders the interpretation of erosion rates and mantles evolution. • Meteoric 10Be serves as a pre-pedogenic erosion tracer. Loess deposits are terrestrial archives that record progressive deposition and erosion events of varying intensities. Data on long-term erosion rates are crucial for tracking changes in the stability of a loess mantle and reconstructing the evolution of loess-enriched soils. We used meteoric 10Be to i) define the factors responsible for its distribution along the profile, ii) determine long-term erosion rates in loess-enriched polygenetic soils characterised by illuviation processes, and iii) evaluate initial soil thickness and stability over time. Distribution of meteoric 10Be along the soil profiles was mainly driven by its translocation with clay particles and accumulation in the illuvial horizons. However, in some cases (loess over serpentinite), the highest meteoric 10Be content was measured in the C horizons which may be related to the longer exposure of serpentinite to meteoric 10Be deposition before the occurrence of a major loess accumulation event. The estimated long-term erosion rates greatly depend on the assumed environmental settings and were in the range of about 0.1–3 t ha−1 yr−1. Based on the soil redistribution rates, we reconstructed the removed loess layer which was from a few dm to about 3 m. The results indicate four main soil evolutionary phases: a) pre-exposure of sediments to meteoric 10Be accumulation; b) formation of thick loess mantles during the Last Glacial Maximum; c) erosion events between 21 and 11.6 ka that significantly shallowed the initial loess mantles; d) pedogenesis (with subsoil clay accumulation) in the Holocene within the thinner relicts of the former Late Pleistocene loess mantle followed by a recent and strong erosional phase due to human impact. These phases are also believed to have occurred in several other areas of Central Europe. [ABSTRACT FROM AUTHOR]

A 11-m-long lake sediment core of a mountain lake situated at 1225 m a.s.l. in the Karkonosze Mountains (Poland) provided a unique, multi-proxy archive to reconstruct natural and human-induced environmental changes over the entire Holocene period. Pollen analyses allowed for the local and regional reconstruction of vegetation history. The chemical composition of the core and the determination of amorphous Fe and Al phases enabled to trace back soil formation in the surrounding catchment. About 11 ka ago, birch-pine and pine-birch communities started to develop in the Preboreal chronozone. Subsequently, the vegetation cover changed to Corylus-Picea-Abies + Fagus in the higher and middle mountain zones, and to Ulmus-Quercus-Carpinus in the mountain foreland and footslopes. The decline of forests that started in the 11th century because of clearing was accompanied by the expansion of grasses, both as pastures in the mountains and cereal crops in the foreland. At the same time, the mining and smelting gave rise to environmental pollution with heavy metals (Pb, Cu and Zn) at a regional scale. Combined geochemical and palynological data indicated relationships between vegetation type, sediment texture and its elemental composition. This relationship seemed to be linked to climatic conditions and surface erosion intensity. A first progressive soil-forming phase occurred from 10.9 until about 8.4 ka cal. BP. Rapid and strong soil erosion (regressive phase), related to rapid climate deterioration, occurred at about 8.4 ka cal. BP. Thereafter, continuous soil formation (progressive phase) and podzolization in the Boreal and Atlantic continued until about 1 ka BP when strong human impact (deforestation) led again to a regressive soil evolution. [ABSTRACT FROM AUTHOR]

• Aeolian silt mantles reveal different clay mineralogy than the underlying substrates. • Aeolian silt admixture was an important source of chlorite. • Smectite and mica have partially been inherited from the underlying bedrock. • Clay minerals transformation determined the presence of vermiculite and smectite. Loess may be integrated into slope deposits at different soil depths and may influence related physical, chemical and mineralogical soil properties. Therefore, tracking the border between deposited loess and underlying materials and estimating the depth of loess penetration is a challenge. Five soils from the Lower Silesia province in south-western Poland having different types of geologic substrate and being covered by loess deposits of various thicknesses were chosen to: 1) trace the origin of phyllosilicates in these heterogeneous soils (loess vs. underlying bedrock); 2) determine the influence of the geologic substrate and the loess mantle on clay mineral transformation in the soil; and 3) relate clay mineralogical traits to soil morphology. The loess consisted of long-distance and local aeolian sources as shown by the Ti/Zr ratios and heavy mineral composition. Geochemical and mineralogical traces of loess were easily detected in the mixed zone and in part also in the basal layer. The loess deposits are characterised by mica, chlorite, kaolinite, interstratified mica-vermiculite or hydroxy-interlayered vermiculite, vermiculite and a minor amount of smectite. Aeolian silt admixture was an important source of chlorite at all sites. The vertical distribution of mica indicated two types of sources — loess input and substrate. Smectite, however, has mostly been inherited from the underlying bedrock (serpentinite, glacio-fluvial deposits and basalt slope sediment) or was formed in the soils from mica or chlorite. Where present in the loess, smectite was only found in small amounts. The presence of kaolinite, HIV and mixed layered mica-vermiculite could be derived either from aeolian input or neoformation and thus actively occurring mineral (trans)formation reactions. Similar to mica, vermiculite was derived from both aeolian input and the geological substrate. The widespread loess deposits in this region rejuvenated the soil formation process, as evidenced by their mineralogical and chemical composition. [ABSTRACT FROM AUTHOR]