Although Pliocene palaeosols can supply palaeoclimate information and help to disentangle stratigraphic reconstructions, soils are sparsely represented in global datasets for Pliocene climate. Pliocene was characterised by global mean annual temperatures 2–4 °C warmer than today, representing an analogue for future climate prevision. We aimed, thus, to investigate palaeosols as suitable archives for reconstructing geomorphic processes, ecosystems and climate patterns in the Pliocene.

We compared the palaeosol record stored in Zanclean and Piacenzian successions locate in central and southern Tuscany, respectively. Palaeosol morphological features observed in the field were used for the sequence-stratigraphic interpretation. To qualitatively evaluate soil development, we considered the time needed to attain various soil properties. Pedogenetic processes and the intensity of weathering were also quantified by applying a range of proxies based on geochemical analyses. Climofunctions based on major element ratios were used to estimate mean annual palaeoprecipitation (MAP). Carbon and oxygen isotopes analysis were performed on carbonate nodules, to verify their pedogenic origin and as a proxy for palaeovegetation and palaeotemperatures.

Though all soils are unconformities in the record, the rank and type of unconformity were defined in detail, to precisely place the soil formation time within the sedimentary sequence and to correlate soil-forming intervals with general environmental changes. Then, soil characteristics were interpreted, considering the geomorphological setting reconstructed by the stratigraphic and sedimentological analysis.

The Zanclean-age soils represent a presumably long-time span, likely a few thousand years, and exhibit strong redoximorphic features such as low-grade plinthite, suggesting that they developed in intervals of humid climate. The mid Piacenzian-age soils represent rhythmic and short intervals of pedogenesis, which correlate to sea level highstands. The main characteristics of palaeosols are due to clay shrink-swell properties (vertic) and carbonate translocation (calcic). Calcic features were interpreted as recording the duration of pedogenesis and thus of the sedimentary hiatuses, suggesting a range of development from 1,000 to 10,000 years. These soil features and the isotopic proxies converge towards indicating a highly seasonal rainfall pattern. This inference matches the sedimentological facies, which point to sediment transport and deposition from highly laden flood flows, recalling the sedimentary dynamics of seasonal fluvial systems. The hypothesis of a very high degree of rainfall seasonality would match well with existing palaeoclimatic records for the Mediterranean Middle Pliocene Warm Period (MPWP), and could shed light on certain unusual features in such records.

Comparing soils developed in the Early and in the Late Pliocene, the MAP estimates confirm the differences in climate condition which likely led to the divergent pedogenesis pathways. Furthermore, the palaeotemperatures estimated from the oxygen isotopic composition of pedogenic carbonates within Piacenzian calcic horizons, point to values matching the modelled temperatures for the MPWP.

How to cite: Andreetta, A., Benvenuti, M., Delgado-Huertas, A., and Carnicelli, S.: Buried palaeosols in Tuscan inland basins provide clues to changing climate conditions across the Pliocene, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7509, https://doi.org/10.5194/egusphere-egu22-7509, 2022.

Quantification of geomorphic processes governing development and long-term stability of vesicular A (Av) horizons in deserts is critical to understanding desert soil genesis and evaluating stability of desert surfaces. Previous attempts to date Av horizons have yielded Holocene ages that are discordant with underlying soil ages, leading some investigators to interpret Av horizons as recently formed features. In contrast, systematic increases in the expression of Av horizon development have been identified from studies that examine trends in soil morphology on Quaternary timescales. This study uses meteoric ¹⁰Be (¹⁰Be_met) as a radiometric tracer in the soil to (1) test the hypothesis that Av horizons are long-lived features in low-relief desert landscapes, and (2) enable improvement of dating techniques applicable to desert soils.

Meteoric ¹⁰Be concentrations were examined for selected soils within a chronosequence from the Mojave Desert, Southern California, USA. The pedons selected for analysis are from an alluvial fan sequence composed of mixed plutonic parent materials sourced from the adjacent Providence Mountains. Samples for ¹⁰Be_met analysis were collected from Av and underlying B horizons of three pedons of varying soil age and from an active alluvial channel to evaluate relationships between ¹⁰Be_met concentrations and soil exposure time. Additionally, two separate peds from the Av horizon of a single pedon were subsampled to evaluate the relative concentrations in four zones within individual Av peds, including the surface, bottom, sides, and interior.

Meteoric ¹⁰Be concentrations from Av horizons range from 6.95x10⁶ at/g (active channel) to 1.09x10⁹ at/g (oldest) and exhibit a systematic increase in ¹⁰Be_met concentration with increasing soil age. Similarly, samples obtained from underlying B horizons in Holocene to Pleistocene soils have ¹⁰Be_met concentrations of 1.34x10⁸ at/g (youngest) to 9.40x10⁸ at/g (oldest). The subsampled Av pedons show apparent physical fractionation of ¹⁰Be_met, primarily towards ped interiors, which contain 1.01x10⁹ to 1.09x10⁹ at/g ¹⁰Be_met. The remainder of the ped exhibits a comparative reduction in ¹⁰Bet_met concentrations by 12-38%. This trend is similar to carbonate and clay-particle trends that also tend to fractionation in Av ped interiors, indicating a greater proportion of moisture content in these zones relative to exterior ped surfaces.

Our preliminary observations strongly support the hypothesis that Av horizons are persistent and stable features in the landscape, contrary to prior studies that attempt to explain universally young Av ages using arguments that favor Av destruction and reformation in response to climate dynamics during and after the Pleistocene-Holocene transition. Our results have several major implications. First, Av horizons strongly influence the flux of water into the soil profile, thereby governing hydrologic, biologic, and pedogenic processes at and below the soil surface. This study will enable detailed investigation of the rates associated with primary moisture and sediment movement in desert soils. Second, our methodologies provide a technique that can be further developed to directly date Av soil horizons independent from the underlying sediment. Finally, our findings have the potential to inform the hydro-pedologic connectivity between Av horizons and underlying soil materials to enable a better understanding of soil genesis in arid environments.

How to cite: Sion, B., McDonald, E., Bustarde, J., and Hidy, A.: Meteoric 10Be analysis from a soil chronosequence in the Mojave Desert, USA reveals the long-term stability of Av horizons and potential avenues for future research , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9963, https://doi.org/10.5194/egusphere-egu22-9963, 2022.

The Chinese loess-paleosol sequences provide valuable records of the Quaternary climate changes. However, the relative contributions of the Quaternary paleoclimate (e.g. precipitation, temperature, evapotranspiration, vegetation and dust addition) on interglacial paleosol development, and which factor plays a key role are inadequately studied in the Chinese Loess Plateau (CLP). Here, we examine the relative contributions of these factors on paleosol development on the CLP by a sensitivity analysis. For this, we simulate paleosol development using the climate-soil model LOVECLIM-SoilGen2.

The sensitivity analysis was done during two interglacials, MIS11 and MIS13, where MIS11 shows quite contrasting climate forcing with MIS-13. Several simulations were run; in each simulation, one parameter is allowed to change at a time (e.g. precipitation), and others are kept constant (as in reference). A reference simulation is included 100-year average values of the end of Holocene simulation mimicking the Pre-Industrial climate. Additionally, combined effects of climatic parameters (e.g. precipitation and evapotranspiration) were investigated, and mean absolute error was calculated between each of the sensitivity simulation and the actual simulation (combination of all soil forming factors).   

Our results show that precipitation has the largest influence on the depth redistribution of soil properties (calcite and clay) in MIS11 and MIS13 and dust addition is the dominant factor affecting the amount of simulated calcite and clay. Our results indicate that potential evapotranspiration has a pronounced impact during MIS13. Unlike the simulated MIS11 paleosol, which is explained by precipitation plus dust addition, the MIS13 paleosol development is better explained when potential evapotranspiration is also taken into account during this extreme interglacial. 

How to cite: Ranathunga, K. N., Finke, P., Yin, Q., and Wu, Z.: Modelling the relative effect of different climate factors, vegetation and dust deposition on the MIS-13 and MIS-11 paleosol development on the Chinese Loess Plateau, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4663, https://doi.org/10.5194/egusphere-egu22-4663, 2022.

The Spatiotemporal Variations of Provenance in the Chinese Loess Plateau by the Sensitivity of Quartz Optical Stimulated Luminescence

Jiao Li^1,*

^1,*Department of Geology, Northwest University, Xi’an710069, China

E-mail: ^1,*nwu_lijiao@163.com

Loess contains a lot of quartz, which is stable in nature and is not easy to be weathered and transformed. It can retain the original rock information, and the response of quartz crystals to radiation energy is obvious. Thus, optical stimulated luminescence (OSL) sensitivity can identify provenance. The magnetic susceptibility reflects the strength of the summer monsoon, and the grain size is a proxy for the winter monsoon. The magnetic susceptibility and grain size have been widely used in the study of Chinese loess as proxy indicators of the East Asian monsoon.

By studying the change of quartz optical stimulated luminescence sensitivity of loess-paleosol in the Xifeng section of the Chinese Loess Plateau, combined with the related work from others in the Chinese Loess Plateau, the provenance changes of the Chinese Loess Plateau in the time-space sequence were analyzed. In the time series, the sensitivity of quartz OSL showed a high value in paleosol, and the highest value was about 2700 counts/Gy/mg. Meanwhile, it exhibited a low value in loess, and the lowest value was about 200 counts/Gy/mg, which is different from paleosol. In the spatial sequence, the OSL sensitivity of quartz from west to east in the Chinese Loess Plateau has a large difference (8-10 times) in the interglacial (paleosol), and a small difference (1-2 times) in the glacial (loess). The sensitivity of quartz OSL preliminarily indicates that the provenance of the Chinese Loess Plateau has changed in time series (loess-paleosol). Moreover, in space sequence (among different profiles), the sensitivity of quartz OSL has changed in paleosol during the interglacial, but has a minor difference in the loess during glacial.

At the same time, combined with the study of magnetic susceptibility and grain size, the quartz OSL sensitivity corresponds well to the fluctuation of the climate proxy index, which shows that the quartz OSL sensitivity is positively correlated with the magnetic susceptibility and negatively correlated with the particle size. The OSL sensitivity and magnetic susceptibility of quartz were higher in the paleosol and lower in the loess; the variation of grain size was the opposite.

Keywords: quartz, optically stimulated luminescence sensitivity, loess provenance, glacial-interglacial, Chinese Loess Plateau

How to cite: Li, J.: The Spatiotemporal Variations of Provenance in the Chinese Loess Plateau by the Sensitivity of Quartz Optical Stimulated Luminescence, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9072, https://doi.org/10.5194/egusphere-egu22-9072, 2022.

The paper describes red-coloured pedosediments (PDs) from four sections of the Lagonaki highlands (1800m), Adygea Republic, Russia. Currently, there are no conditions for the development of such formations in this region due to climate change. But a tropical climate sufficient for the formation of red-coloured PDs dominated the area in the Lower Pleistocene or earlier. Since the signs of soil formation persist for the longest time in the lower horizons, we attempt to establish their age and develop conditions. The parent rock is carbonate deposits, but PDs erosional displacement is diagnosed by the absence of regularities typical for the genetic soil profile. Thus, when diagnosing soil formation processes, we cannot be guided by the modern topographic position of the studied objects and unstable (=modern) features.

According to micromorphological, particle size, chemical composition, and magnetic susceptibility analysis, fersiallite or ferralitic soil formation was established, but with variations. Almost all samples have high weathering indexes (CIA=1.8-2.5; Rb/Sr =1.3-2.4) and TiO2 content (0.8-1.1%). So, in the upper sample of the first section, signs of strong leaching were revealed, grains of hematite were found, a heavy particle size composition (52% - silt and colloids), high weathering indexes, relatively high content of Al2O3 and Fe2O3, and a high magnetic susceptibility (MS) index (22*10-8).

The underlying horizon is likely not to move and continues to develop with the weathering of the underlying limestone, judging by the low weathering indexes. However, strongly weathered quartz grains were found in it, which may be attributed to the result of acidic humid soil formation. The particle size composition can also be a sign of the duration of soil formation: 39% of silt and colloids.

The sample from the second section has vertic signs: iron-clay coatings and specific cracks. This is the most dolomitic and sandy (70% physical sand) layer, it contains the minimum of non-silicate forms of iron, average weathering coefficients, but quite a lot of TiO2 (0.83%). Also, due to the increased amount of diamagnetic carbonates, the MS index is minimal here.

In the third studied section signs of gleying are diagnosed. And according to the cracking of the soil mass - signs of vertic processes. Hematite grains are also present. Deep weathering processes are reflected in high weathering indexes and MS index (25.5*10-8), the content of silt and colloids (40%).

The fourth section consists of two layers. The upper one is distinguished by the amount of K2O, which is associated with clay particles in the soil – an indication of a long and strong modification of the rock. This is consistent with the high content of Al2O3 (23.4%), high weathering coefficients, MS (15.9*10-8), particle size composition (43% - silt and colloids).

The underlying layer is similar to the upper layer with similar content of Al2O3 and TiO2, high weathering coefficients, MS, clay granulometric composition, but it has a higher content of Fe2O3 and leaching index.

The study was supported by the RFBR, project N19-29-05024mk

How to cite: Revunova, A. and Khokhlova, O.: The red-coloured pedosediments of the Lagonaki highlands (Adygea Republic, Russia), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13257, https://doi.org/10.5194/egusphere-egu22-13257, 2022.

Archaeomalacological analysis is generally undertaken on recovered macro-remains to characterize the overall composition of faunal remains in a deposit. Given the susceptibility of shell middens to a variety of taphonomic processes, it is assumed that the prior presence of shell in deposits may therefore occasionally be missed. Deteriorated micro-remains can mix indistinguishably into surrounding sediments and make their analyses and identification difficult, particularly in older deposits and in environments that experience rapid rates of weathering. This paper explores whether microscopic remains of deteriorated molluscs can be distinguished from other microscopic remains at the coastal rock shelter site of Waterfall Bluff in Mpondoland, South Africa. The methodology uses a multi-scalar approach integrating shell mineralogy and microstructure using the taxonomic distinctiveness of these features. The diagnostic features (e.g. morphology, hinges, spires, and apertures) used for identifying macro-remains are absent in micro-remains, therefore unique methods of identification are needed to identify these microscopic mollusc fragments. Through mineralogical analyses and scanning electron microscope (SEM) imaging, the nacreous remains of mussel shell were identified from previously unidentified degraded shell remains as well as sediment samples from Waterfall Bluff. These highly degraded remains were located under the dripline in the oldest deposits (LBCS) which are sharply comparable to the more well-preserved macro mollusc evidence in the younger (SRCS) deposits. These methods recovered ‘invisible’ evidence of shellfish remains, which led to additional and clearer evidence of continued coastal foraging from Marine Isotope Stage 3 to the early Holocene (40 ka to 10 ka) on the South African coast.

How to cite: Oertle, A., Szabó, K., Gaqa, S., Cawthra, H., Esteban, I., Pargeter, J., and Fisher, E.: Identifying taxa from highly degraded shell micro-fragments in anthropogenic soils from Waterfall Bluff, South Africa, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4341, https://doi.org/10.5194/egusphere-egu22-4341, 2022.

In the North European Lowland, on the sandy deposits of the Weichselian glaciation, soils developed during periods of landscape stability are often conserved under windblown sand. However, small-scale changes of sediments and other soil forming factors can result in high spatial variation of soil properties in these landscapes; and relocation of soil material by geomorphic processes further increases the spatial heterogeneity of the soil landscape. These spatial variations in soil properties and conservation need to be considered in order to correctly decipher and interpret the buried soils as records of past environmental conditions.

In the forefield of the open-cast mine Cottbus-Nord, archaeological excavations in a dune and drift sand area revealed widespread buried soils of different characteristics. The densely spaced excavation trenches give exceptionally good insights into the pedosphere, allow for reconstructing the distribution of fossil and recent soils in a high spatial resolution, and offer good opportunities to improve the understanding of spatial and temporal patterns of soil formation. Remains of postpleistocene hunter-gatherer campsites were documented in archaeological excavations and found to be associated with a buried soil horizon.

We recorded the stratigraphy of soil profiles along more than 15 trenches within an area of about 20 ha, and additionally described the position of buried soils from GPR surveys and microdrone photogrammetry. In a recently opened, 455 m long trench, all characteristic soils and sediments of the study region could be observed and stratigraphically connected. Within this trench, four profiles were identified for further research. Each profile was classified and described according to WRB and German Guidelines for Soil Mapping; and was sampled and investigated through laboratory analyses including determination of organic matter, total carbon and nitrogen contents, soil colour identification, texture analysis, magnetic susceptibility measurement, metal content analysis using X-ray fluorescence analyzer and pH measurement. The compaction and cementation of soil horizons was assessed in situ with a pocket penetrometer.

Results show a small-scale mosaic of soils developed on fluvio-aeolian, limnic and aeolian sediments, high spatial variations in pedogenesis due to varying groundwater influence and intensity of horizontal and vertical leachate transport, and high variations in the erosion or conservation of fossil soils. The soil and sediment stratigraphy reflects several phases of landscape development: i) the formation of a Late Pleistocene soil on fluvio-aeolian deposits, ii) a fossilization by aeolian sands, iii) a stability phase with intensive podsolization and peat formation, and iv) a land use-induced aeolian remobilization of the sands. 

How to cite: Uchino, K., Raab, A., Bonhage, A., Schneider, A., Raab, T., Wechler, K.-P., and Bauriegel, A.: Spatial heterogeneity of buried and recent soils in a drift sand area in North-Eastern Germany, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-2354, https://doi.org/10.5194/egusphere-egu22-2354, 2022.

Colluvisols represent an important part of the soil cover, occupying concave slope elements especially in landscapes with undulating relief. Their development reacts to changes in land use or climate, manifested by intense erosion activity or longer resting periods with predominantly in-situ pedogenesis. In climatically, pedologically and historically different regions, diverse colluvial profiles can be encountered. In this study, we investigated deep colluvial profiles in three agricultural plots in Czechia with different soil cover, climatic and geological conditions in order to identify differences in the depositional pattern and erosion history of the areas. In each of the plots, two profiles (depths ranging from 200 to 400 cm) were opened in the toe-slope and side valley areas. Individual layers were investigated by various methods, including optically stimulated luminescence dating, 137Cs activity, concentration of vertically stable geochemical tracers (organochlorine pesticides, nutrients) or micromorphology and clay mineralogy, allowing the layers to be linked to periods of human activity. In all study areas, a significant difference in the colluvial deposition mechanism was found in the toe-slope and side valley areas. While the positions in the side valleys were mainly composed of older material with a minimum concentration of human-bound substances, the profiles in the toe-slopes are characterized by a significant deposition of recently accumulated material. The most pronounced redistribution of material was recorded in the Chernozem area on loess. In the toe-slope area, maxima of 137Cs, DDT (up to 350 µg/kg) and phosphorus were found at 100-140 cm, indicating the very low age of this layer (from the mid-20th century). The mineralogical and chemical composition of this layer and the layer below (140-220 cm) shows considerable similarities to the substrate material, indicating severe truncation of the source soils and accumulation of ploughed parent material. In contrast, in the side valley, this new material was found only in the topsoil, with approximately 3 m of older, humus-rich material beneath. This area is therefore not an area of recent deposition, but rather of material transport. The original buried Chernozem was found in both cases at a depth of about 300-350 cm. In the Cambisol area, the combination of rill and sheet erosion led to the formation of a highly stratified profile with a large variation in texture or humus content. The maximum of human-bound substances (137Cs, HCB, DDT) was found at a depth of 1 m, underlain by older material with signs of post-depositional pedogenesis (weathering and redox processes). The area of side valley was, as in the previous area, almost unaffected by recent sedimentation. In Luvisol area, the concentration on human-bound substances was generally lower and affected only the upper, humus-rich layer (ca 80 cm) of the Colluvisols, both at the toe-slope and the side valley. Below this layer, the profiles are characterised by relatively pronounced pedogenesis in the sedimentary material (clay coatings visible at the thin sections), indicating slower sedimentation and a longer period of sedimentary quiescence.

Study was supported by grant nr. 21-11879S of the Czech science foundation and MEYS CR project nr. CZ.02.1.01/0.0/0.0/16_019/0000845.  

How to cite: Zádorová, T., Penížek, V., Koubová, M., Žížala, D., Kodešová, R., Drábek, O., Tejnecký, V., Fér, M., Klement, A., Nikodem, A., Hrdlička, T., Reyes Rojas, J., Spasic, M., Vokurková, P., Pavlů, L., Němeček, K., Vaněk, A., and Lisá, L.: Identification of the phases and mechanisms of Colluvisols formation in different soil regions, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1520, https://doi.org/10.5194/egusphere-egu22-1520, 2022.

Common anthropogenic surface features across Scotland and Ireland are raised beds, which are agronomic ridges and furrows created prior to the 20^th century to improve agricultural yield. Creating a raised bed improves yield by providing to the root zone better soil drainage, suitable micro-climatic conditions, and enrichment of organic matter and nutrients. Raised beds are structurally identifiable and can be examined using remote sensing techniques such as LIDAR imagery or aerial photography to analyze different dimensions of raised bed units. We examined the geomorphic parameters (height, length, breadth, ridge shape, furrow depth, unit orientation and block size) of raised beds found in the Fancroft region of County Offlay, Ireland. We developed a model of raised bed structural components and the distribution and change in soil properties including soil drainage, texture, horizon differentiation, soil colour, nutrient distribution, organic matter movement and the carbon influx and outflow have been provided. Our study aims to elucidate the typical geomorphic properties of raised bed landscapes, their basic chemical and physical soil properties and the landform attributes that may influence soil properties. Overall, the conceptual basis of raised bed landscapes have been visualised and presented to formulate an ideal raised bed theoretical model. Such a comprehensive model can be further extended to learn more about ancient agricultural practices, heritage, a causal link between present day and historical farming practices.

How to cite: Sekhri, S., Raab, T., and Drohan, P. J.: A Model Approach Assessing The Soil Properties Of Raised Bed Landscapes , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7137, https://doi.org/10.5194/egusphere-egu22-7137, 2022.

Agricultural terraces are a well-known phenomenon in mountainous regions throughout the globe. Those structures are said to have been in the service of agriculture for several hundred or several thousand years. In different places and environments, terraces had different roles. It has been claimed that its primary goal in the sub-humid and semi-arid environments, was to preserve winter precipitation water within the terrace body. Endemic and domesticated vegetation will then flourish utilizing this resource throughout the dry summer season. Agricultural terraces are widely described in the literature as having three main parts, (a) the base, which is normally a naturally inclined bedrock surface, (b) a manmade retaining wall supporting the weight of (c) the terrace body, usually made of soil and gravel. The terrace base is described in all reviewed literature as an impermeable rock layer. However, previously published calculations suggested that in the sub-humid main mountain ridge of Israel, evapotranspiration will prevent retaining water even in a thick terrace body for the entire summer period. Moreover, in many terraces scattered across the given area, a few centimeters thick soil body seems to support decades and centuries old trees. Therefore, water retention mechanism in the agricultural terraces has been examined. Our study indicate that karst substratum is the controlling factor on terrace water retention. We propose that a well-developed, soil filled, karst system at the terrace substratum impedes the conventional evaporation process of a simple homogeneous soil parcel. Under such conditions, thin body terraces are able to support non-irrigated ancient agriculture water demand in sub-humid environment.

How to cite: Inbar, N. and Ackermann, O.: The role of karstic substratum of ancient mountainous agricultural terraces at the semi-arid environment , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6196, https://doi.org/10.5194/egusphere-egu22-6196, 2022.

Plot-and-Berm agroecosystems agriculturally utilized marginal lands in a sophisticated fashion, where a high-water table existed within loose, aeolian sand sheets, in semi-arid to Mediterranean climates. The agroecosystems consist of polygonal (~10⁴ m²) agricultural plots sunken between ~5 m high berms. Here we focus on the role of sandy anthrosediments and anthrosols, based on analyzing stratigraphic sections in remains of a Plot-and-Berm agroecosystem, 2 km south of ancient Caesarea (Israel). Geoarchaeological methods included pedological analysis, penetrometer measurements, GIS-based mapping, and portable luminescence (PPSL) and OSL for the analysis of construction and possibly maintenance stages.

Ceramics and glass date the agroecosystem to the 10^th-11^th centuries (Early Islamic period) that are compatible with preliminary published OSL ages. Preliminary finds hint to a sand substrate mixed during Roman times. Anthrosols in the plots have distinct upper and lower boundaries with limited root casts suggesting that the Early Islamic crops were annual and not woody perennial species like vines. The anthrosol is currently only 1 m above the modern groundwater table, which appears to have enabled easy access by hand-dug pits for manual irrigation practices per plot. Their topographic setting probably provided protection of the soil and crops from aeolian erosion.

The anthrosols and anthrosediments have geochemical and textural properties that appear to reflect their role. Anthrosols were enriched to enhance soil productivity. Berm crests and slopes were coated with ~0.3-0.7 m thick and dark anthrosediments that were topped with flat pebble to cobble size artifacts. This coupling remarkably preserved the berm morphology and the whole agroecosystem from aeolian and fluvial erosion until modern times. Light grey anthrosediments comprised the internal berm fill. Additional results will help assess the social-economic effort needed to develop and maintain this agroecosystem, and its relation to ancient Caesarea.

How to cite: Ostrowski, A., Taxel, I., Bookman, R., Robins, L., and Roskin, J.: Role of Anthrosols and Anthrosediments in the Early Islamic Plot-and-Berm Agroecosystem by Ancient Caesarea, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9973, https://doi.org/10.5194/egusphere-egu22-9973, 2022.

Our research on spatially bounded Iron Age enclosure of the Viereckschanze type in southern Bohemia made it possible to distinguish the anthropogenic influence of the Iron Age from modern human activities. We collected over 456 samples from 200 cores to a depth of up to one metre. Samples were measured using pXRF to determine the content of the following elements: Al, Si, P, K, Ca, Ti, Mn, Fe, Cu, Zn, As, Rb, Sr, Zr, Pb, and LE – ‘light elements’). Subsequent isometric log-transformation of ppm elemental contents and PCA allowed to distinguish the prehistoric anthropogenic influence from the current modern one. The result of the analysis is as follows: 1) the P signal typical for archaeological settlements was found mainly outside of the enclosure; 2) the conventional anthropogenic signal from the inside of the enclosure was only represented by Mn; 3) other elements related to possible anthropogenic activities were revealed only after applying statistical analysis (As, Pb, Zn, Cu); 4) the unusual manifestation of Si and Ti was connected to the archaeological contexts. The combination of these results (Cu, Zn, Pb) and magnetic measurements revealed places of metallurgical activity inside Viereckschanze. It is certain that the site was not only a place of residential activity, but also of production activity. Viereckschanze was only occupied for a short period of time.

The presented abstract is adapted from the article published in Catena in 2022.

Acknowledgements:

How to cite: Janovský, M., Danielisová, A., Horák, J., Strouhalová, B., and Bursák, D.: How to determine the anthropogenic signal at less settled spatially bounded archaeological sites?, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-2222, https://doi.org/10.5194/egusphere-egu22-2222, 2022.

A late Chalcolithic period site was discovered in central Tel Aviv during a salvage excavation that was conducted by the Israeli Antiquities Authority. The remains included 113 pits and shafts which were divided according to their shape into four groups:

Group 1: Round pits: a group that includes three types: small (0.5–0.6m diameter); medium (c. 1m); large (c. 2m). Some pits contained brown sediment mixed with ceramic fragments, animal bones, and flint; others had no archaeological finds.

Group 2: Bell shape pits

Group 3: Narrow, deep shafts 1–2m diameter, 3–6m deep. This group includes three types of shafts that differ from each other according to their shape: shafts with uniform width; conical shafts narrowing towards the bottom; shafts with a wide niche in the lower third. In some of the shafts, the fill consisted of brown sediments; some contained archaeological finds and some did not. In some of the shafts, the fill contained fragments of aeolian sandstone, sand, and anthropogenic brown sediment on top that sealed the fill.

Group 4: Shaft that opens into an underground space. Only one shaft like this was exposed.

Many questions arise about the function of these diverse shafts including why were so many of them mined?

Examination using the pOSL (portable luminescence method), showed that some of the shafts were used for a long time, and some were probably used for a short time, or not at all. From this, it can be assumed that the large number of shafts may be the result of trial-and-error style probing.

The pits which contained sand and rock fragments (group 3) had a section with a wide niche in the lower third and a thin clay layer. This suggests that these shafts served as water wells for the site inhabitants, which raises a further question: why was it necessary to dig wells along the Ayalon River? 

This will be discussed in the presentation

How to cite: Ackermann, O., van den Brink, E. C. M., Jakoel, E., Anker, Y., Roskin, J., and Asscher, Y.: The Secret of the Chalcolithic Shafts: Insights from the Portable Luminescence Method (pOSL), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6188, https://doi.org/10.5194/egusphere-egu22-6188, 2022.

Charcoal has been produced for centuries, even millenia, in and near forested areas in Europe. The relics are increasingly studied to inform, e.g., on forest composition and woodland exploitation, the effects of biochar on soil properties and plant nutrients, and carbon sequestration. All these studies require a chronological framework, which is most commonly established using radiocarbon (¹⁴C) dating. In NW Europe, however, many relic charcoal kilns have been found to post-date 1650 CE. Owing to limitations imposed by the calibration curve for the last few centuries, ¹⁴C dating results in wide age probability distributions; this implies that the method does not allow resolving the chronology for post-1650 CE features.

In this study, we report on our experiences with optically stimulated luminescence (OSL) dating as a complementary and alternative method to ¹⁴C. The approach uses sand-sized quartz extracted from sediments that were heated during charcoal production. Our study comprises relic charcoal kilns on silty and sandy subsurfaces in Belgium (Sonian and Zoersel forest), The Netherlands (The Veluwe) and France (Grand-Est region). We first demonstrate that OSL dating can yield accurate and precise ages by comparing our results for pre-1650 CE features with independent (¹⁴C) age information. Intricacies, possibilities and limitations are discussed. For most of the features, widely adopted OSL procedures can be applied; for one of the study areas (Zoersel forest, in the northern Belgian sand belt), dedicated analysis using single grains of quartz is the method of choice. We then apply our methodology to post-1650 CE features, for which ¹⁴C dates and or historical information is available. We show that, for the majority of the investigated features, accurate OSL ages can be obtained with a precision that is similar or significantly better compared to independent age information. A considerable added value is the potential of OSL dating to distinguish between multiple features at one or comparable sites with an unprecendented time-resolution of 5 - 40 years (and 95.4% probability).  

 Keywords: OSL dating; radiocarbon dating; relic charcoal kiln; Modern age; natural resources.

How to cite: Karimi Moayed, N., Vandenberghe, D., Buylaert, J.-P., Deforce, K., Debeer, A.-E., Biernacka, P., De Smedt, P., De Clercq, W., and De Grave, J.: Optically stimulated luminescence dating of relic charcoal kilns using sand-sized quartz: a status report, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13221, https://doi.org/10.5194/egusphere-egu22-13221, 2022.

In the Tauer Forest, a woodland area north of the city of Peitz (Brandenburg, Germany), extensive charcoal burning was carried out from the mid-16th century to the mid-19th century resulting in numerous Relict Charcoal Hearths (RCHs). The most prominent feature of the soils on RCHs is the anthropogenically modified 20-30 cm thick RCH substrate that buries the former forest soil. The RCH substrate is a quite heterogenous mixture of mineral and organic compounds which were modified through heat during charring. It is characterized by its black color resulting from charcoal fragments (from fine dust to decimetre size pieces), lower bulk density, and higher porosity.

After their use, the charcoal production sites were abandoned and soon became overgrown. Soil formation could commence in this anthropogenically modified RCH substrate. During recently conducted field work on RCHs in the Tauer Forest we detected features of initial podzolisation (bleaching of quartz grains) within this RCH substrate. To further investigate initial processes of soil formation (acidification, podzolisation, accumulation of soil organic matter) on RCHs, two different RCH sites were selected in the Tauer Forest: one RCH site in the forest district Tannenwald and one RCH site in the forest district Kleinsee.

The Tannenwald site (RCH no. 29958) is situated in the western part of the Tauer Forest. It is an inland dune area with a coniferous forest (Scots pine, Pinus sylvestris L.) plantation. The forest soils are Podzols and the soils on the RCHs are classified as Spolic Technosols.  The dense undergrowth consists of mainly blueberry (Vaccinium L.). Dendrochronological ages (determination by K-U Heußner, DAI Berlin) of charcoal pieces proof, that the charcoal hearth was used after 1655.

The Kleinsee site (RCH no. 29424) is situated in the eastern part of the Tauer Forest. The parent material is sand from glaciofluvial sediments of the Weichselian glaciation. The forest soils are Brunic Arenosols (Protospodic) and the soils on the RCHs are classified as Spolic Technosols (Arenic). The deciduous forest is dominated by sessile oak (Quercus petraea (Matt.) Liebl.). The undergrowth is only scarce with some ferns (sporadic), blueberry (Vaccinium L.), some shoots of rowan (Sorbus aucuparia L.)  and some moss. There is no dendrochronological age available from the RCH, but RCHs nearby were dated from the 18^th to the 19^th centuries.

At both sites, three soil monoliths were sampled on the RCH platform and three monoliths from the natural forest soil as reference soils. The soil monoliths were sampled continuously in 3 cm vertical spacings. Following lab analyses were carried out: pH (CaCl₂), pH (H₂O), total carbon (TC), total nitrogen (TN), CECeff and total concentrations of selected elements. Analyses of pedogenic Fe are in progress. First results of these study will be presented and discussed.

How to cite: Raab, A., Kim, M., Bonhage, A., Schneider, A., Raab, T., and Bauriegel, A.: Initial processes of soil formation on Relict Charcoal Hearths (RCHs) in the Tauer Forest (Brandenburg, Germany), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3563, https://doi.org/10.5194/egusphere-egu22-3563, 2022.

Soils on relict charcoal hearths (RCHs), i.e. aged charcoal rich Technosols, feature documented legacy effects regarding their physical and chemical soil properties. These forest soils result from the pre-/early-industrial production of charcoal in upright standing hearths. Today, RCHs are found in forested areas as circular microrelief structures with average diameters of about 10 meters that contain technogenic soil horizons of about 20 cm thickness. RCH soils are most distinctly characterized by their large content of pyrogenic soil organic matter and consequently increased total carbon contents. The resulting changes in the soils’ cation exchange capacity, soil acidity, total nitrogen contents and total element stocks are often significant. Furthermore, changes in soil physical properties like a lower bulk density and a higher porosity result in changed soil-water- and temperature regimes. Combined, these effects potentially result in unique soil microhabitats that are restricted to relatively small, clearly defined areas in many forest ecosystems.

Recent studies on RCH soils increasingly focus on potential changes in microbiological and vegetational composition and abundances and report diverse effects. Here, we study the effects of century old charcoal rich Technosols on the drought sensitivity of Scots pine (Pinus sylvestris L.) on three RCH sites located in Lower Lusatia, Saxony (Germany). Through dendrochronologial analysis of increment cores and historical climate data, we study climate-growth relationships for trees on RCH soils and reference forest soils for two periods (AD 1963-1992 & AD 1990-2019). Furthermore, we determine pointer years and components of resilience to quantify the trees’ reaction to extreme weather conditions. This analysis was accompanied by soil sampling and analysis on the RCH sites and adjacent reference forest soils. Here, we present preliminary results and discuss them in the context of findings from other studies on RCH soils.

How to cite: Al Jobayer, M. A., Bloß, K., Porsch, C., van der Maarten, E., van der Maaten-Theunissen, M., Bonhage, A., Raab, A., Schneider, A., and Raab, T.: Drought sensitivity of Pinus sylvestris L. on century old charcoal rich Technosols in the North-German Lowland, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7978, https://doi.org/10.5194/egusphere-egu22-7978, 2022.

The mining region of Upper Silesia has a long tradition with international significance. In 2017, the historic silver mine in Tarnowsky Gory was recognized as a UNESCO World Heritage Site. With the mining of galena (PbS), the region developed into one of the most important industrial centers in Central Europe in the 16th century. In addition to the underground galleries, the historical mining has left thousands of mining shafts as small relief forms, which have not been systematically investigated so far. Partly the mining shafts are associated with Relict Charcoal Hearths (RCH), another small form which is a result of charcoal production. In the Mala Panew River valley, north of Tarnowsky Gory, several tens of thousands of these RCH are found, which could be mapped by LiDAR in recent years. More detailed pedological investigations, which would allow a systematic comparison with other known RCH sites, are missing so far.

Within the framework of a Polish-German cooperation project, we started in 2021 to investigate the mining shafts and the RCH in Tarnowsky Gory and in the Mala Panew River valley from a pedological-sedimentological point of view. At the RCH sites on the Mala Panew River, we focused on the following questions: How was the soil stratigraphy changed by the RCH construction? What are main processes of soil development before and after RCH construction? What was the role of the pits surrounding the RCH? How do the sites differ from the RCHs at Tarnowsky Gory especially with respect to soil properties and soil genesis? In Tarnowsky Gory, where a RCH was excavated directly next to a mining shaft, the following questions were in focus: How did the mining activity change soil distribution and soil properties? What are main processes of soil development on the different parts? What is the origin of the pit infill? What is the origin of the shaft rim deposits?

Our work program included the construction of excavator trenches across the mining remains, construction, description and sampling of soil profiles along the trenches, schematic drawing of the soil stratigraphy, and laboratory analyses for the determination of texture, Munsell color, pH (CaCl2, H20), CaCO3 content, Ctotal & Ntotal and total elements by FPXRF. We present the first results of the ongoing investigations.

How to cite: Raab, T., Bonhage, A., Verschoof-van der Vaart, W., Malik, I., Raab, A., Schneider, A., Chauhan, J. S., and Thekkethala, J. J.: Soils on mining relicts in Upper Silesia, Poland – first results from the Mala Panew River catchment and the UNESCO heritage site Tarnowskie Góry , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-969, https://doi.org/10.5194/egusphere-egu22-969, 2022.