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Abstract Chernozems/Phaeozems are important agricultural resources and have been intensively used for millennia. However, their origin and age are still controversial. In Europe, the westernmost widespread Chernozem/Phaeozem area is located in Central Germany. In contrast to other German regions with anthropogenic Chernozems/Phaeozems, their natural origin is suggested in connection with intensive bioturbation. Yet, radiocarbon is unsuitable for decoding Chernozem/Phaeozem formation so this hypothesis remains untested, whereas single-grain luminescence dating allows to discriminate between different soil sub-processes and formation phases. We applied single-grain feldspar luminescence to a Central German Chernozem that was buried during the Bronze Age and subsequently protected from pedogenic processes. For the first time, we could directly determine timing and rate of Chernozem/Phaeozem formation in Central Europe by dating bioturbation as the dominant soil forming process. Accordingly, Chernozem/Phaeozem formation started at the latest in the Early Holocene prior to Neolithic settlement indicating a natural origin of Central German Chernozems/Phaeozems, and Chernozem/Phaeozem formation ceased around 6–5 ka when the regional climate became more humid. Our effective soil reworking rates show that earthworm bioturbation in Chernozems/Phaeozems is more intense than ant-dominated bioturbation, but significantly less intense than bioturbation by lugworms or ploughing. The latter effect allows to identify prehistoric ploughing in paleosols.

Dryland soil salinization strongly affects soil properties, with severe consequences for regional ecology, agriculture and the aeolian dust dynamics. Given its climate-sensitivity it forms a serious environmental hazard, and to cope with this challenge during current global warming it needs to be better understood. The Bajestan Playa in the strongly salinization-affected Iranian drylands hosts several protected areas and forms an important regional dust source. Hence, soil salinization in this region affects local and regional ecosystems and societies, but was not systematically studied yet. Using an unprecedented comprehensive approach we systematically monitored regional soil salinity 1992–2021 using remote sensing as well as on-site field and laboratory measurements, and linked these with regional and global climatic data to understand (i) the spatio-temporal soil salinity dynamics, (ii) the impact of regional and global climate changes, and (iii) the potential of our approach for further soil salinity studies.Our annual time resolution over three decades provided significantly deeper and unprecedented insights into soil salinization: Both regional annual precipitation and temperature control soil salinity, but the latter responds to precipitation with time lags of up to two years and to higher temperatures without any time lag. This probably reflects the transport time of leached soluble salts from their sources following humid years. No systematic soil salinity changes were observed within the playa basin, but outside the basin soil salinity systematically increased. Whereas regional precipitation did not show a systematic trend during the last decades, regional temperature increased and was mostly correlated with the increasing GLOTI, POL and TSA climatic indices. Hence, given ongoing global warming a further increase of regional soil salinization should be expected, with serious consequences for saline dust emissions, the regional protected areas and climate-related migrations. Altogether, our multi-disciplinary pioneer study demonstrates a high future application potential also for other salinity-affected drylands, forming a base to deal with the consequences of ongoing global climate change.

Abstract The Marine Isotope Stage (MIS) 2 is considered the coldest, driest and stormiest period during the last Glacial-Interglacial cycle in large parts of Eurasia. This resulted from strongly decreased northern hemisphere temperature and related maximum extension of northern ice sheets that strongly reinforced large-scale circulation modes such as westerlies and East Asian Winter Monsoon driven by the Siberian High. Normally, this intensified circulation is reflected by maximum loess deposition in numerous loess regions spanning Europe and Asia. However, here we present a new loess record from the Caucasus region in NE-Armenia providing evidence in support of heavily reduced or even lacking loess formation during the MIS-2. Owing to implementations of comprehensible luminescence dating work and a provenance survey using rock magnetic and geochemical data, we are able to define distinct loess formation phases and to retrace sediment transport pathways. By comparing our results to other Eurasian palaeo-records, we unveil general atmospheric circulation modes that are most likely responsible for loess formation in the Southern Caucasus. Moreover, we try to test different scenarios to explain lacking loess formation during MIS-2. In line with other archive information, we suggest that loess formation was hampered by higher regional moisture conditions caused by a southward-shift of westerlies and renewed moisture absorption over the Black Sea. Our results show that modifications of MIS-2 circulation modes induced a very heterogeneous moisture distribution, particularly in the lower mid-latitudes of Eurasia producing a juxtaposition of very dry (morphodynamically active) and moderately dry (morphodynamically stable) areas.

Long-term human-environmental interactions in naturally fragile drylands are a focus of geomorphological and geoarchaeological research. Furthermore, many dryland societies were also affected by seismic activity. The semi-arid Shiraki Plain in the tectonically active southeastern Caucasus is currently covered by steppe and largely devoid of settlements. However, numerous Late Bronze to Early Iron Age city-type settlements suggest early state formation between ca. 3.2-2.5 ka that abruptly ended after that time. A paleolake was postulated for the lowest plain, and nearby pollen records suggest forest clearcutting of the upper altitudes under a more humid climate during the Late Bronze/Early Iron Ages. Furthermore, also an impact of earthquakes on regional Early Iron Age settlements was suggested. However, regional paleoenvironmental changes and paleoseismicity were not systematically studied so far. We combined geomorphological, sedimentological, chronological and paleoecological data with hydrological modelling to reconstruct regional Holocene paleoenvironmental changes, to identify natural and human causes and to study possible seismic events during the Late Bronze/Early Iron Ages. Our results show a balanced to negative Early to Mid-Holocene water balance probably caused by forested upper slopes. Hence, no lake but a pellic Vertisol developed in the lowest plain. Following, Late Bronze/Early Iron Age forest clear-cutting caused lake formation and the deposition of lacustrine sediments derived from soil erosion. Subsequently, regional aridification caused slow lake desiccation. Remains of freshwater fishes indicate that the lake potentially offered valuable ecosystem services for regional prehistoric societies even during the desiccation period. Finally, colluvial coverage of the lake sediments during the last centuries could have been linked with hydrological extremes during the Little Ice Age. Our study demonstrates that the Holocene hydrological balance of the Shiraki Plain was and is situated near a major hydrological threshold, making the landscape very sensitive to small-scale human or natural influences with severe consequences for local societies. Furthermore, seismites in the studied sediments do not indicate an influence of earthquakes on the main and late phases of Late Bronze/Early Iron Age settlement. Altogether, our study underlines the high value of multi-disciplinary approaches to investigate human-environmental interactions and paleoseismicity in drylands on millennial to centennial time scales.

This manuscript documents geological master data and X-ray fluorescence (XRF) data of a standardized 8*8 km sampling grid of the entire Weiße Elster catchment in Central Germany. Further, the manuscript documents XRF data of a refined 4*4 km sampling grid in the proximity of Salsitz floodplain transect as well as grain size data and XRF data of Salsitz SC40 core that was recovered from the Weiße Elster floodplain. The data provide opportunities for hydro-sedimentary provenance analyses as presented in the corresponding research article by Ballasus et al. [1].

The paper investigates potentials and challenges during the interpretation of prehistoric settlement dynamics based on large archaeological datasets. Exemplarily, this is carried out using a database of 1365 Neolithic sites in the Weiße Elster river catchment in Central Germany located between the southernmost part of the Northern German Plain and the Central Uplands. The recorded sites are systematically pre-processed with regard to their chronology, functional interpretation and spatial delineation. The quality of the dataset is reviewed by analyzing site distributions with respect to field surveys and modern land use. The Random Forests machine learning algorithm is used to examine the impact of terrain covariates on the depth of sites and pottery preservation. Neolithic settlement dynamics are studied using Site Exploitation Territories, and site frequencies per century are used to compare the intensity of land use with adjacent landscapes. The results show that the main trends of the Neolithic settlement dynamics can be derived from the dataset. However, Random Forests analyses indicate poor pottery preservation in the Central Uplands and a superimposition of Neolithic sites in the southernmost part of the Northern German Plain. Throughout the Neolithic the margins between soils on loess and the Weiße Elster floodplain were continuously settled, whereas only Early and Late Neolithic land use also extended into the Central Uplands. These settlement patterns are reflected in the results of the Site Exploitation Territories analyses and explained with environmental economic factors. Similar with adjacent landscapes the Middle Neolithic site frequency is lower compared to earlier and later periods.

Wetland environments, with their excellent conservation conditions, provide geoarchaeological archives of past human activities. However, the subsurface soil is difficult to access due to high groundwater tables, unstable sediments, and the high cost of excavation. In this study, we present a ground-based non- and minimal-invasive prospection concept adapted to the conditions of wetlands. We investigated the Fossa Carolina in South Germany, a canal that was intended in 792/793 AD by Charlemagne to bridge the Central European Watershed. Although the resulting Carolingian banks and the fairway with wooden revetments are very imposing, archaeological traces of off-site construction activities have not been identified hitherto. Based on a geophysically surveyed intensive linear magnetic anomaly parallel to the Carolingian canal, we aimed to prove potential off-site traces of Carolingian construction activities. In this context, we built up a high-resolution cross-section using highly depth-accurate direct push sensing and ground-truthing. Our results showed the exact geometry of the canal and the former banks. Thus, the magnetic mass anomaly could be clearly located between the buried organic-rich topsoil and the Carolingian banks. The thermoluminescence dating showed that the position of the magnetic mass anomaly reflected Carolingian activities during the construction phases, specifically due to heat exposure. Moreover, we found hints of the groundwater supply to the 5-metre wide navigable fairway.

Fluvial sediments are valuable paleoenvironmental archives of the Quaternary. Since besides environmental factors they are also affected by local tectonics or intrinsic processes, large instead of small catchments should be studied. In drylands covering ca. 45% of the global terrestrial surface large river systems are generally missing, and most river systems are small rivers originating from mountain ranges. Their sediments are potentially interesting paleoenvironmental archives, but are often affected by intensive tectonics. During this study, to obtain a robust regional paleoenvironmental signal a small river system in the southwestern Binaloud Mountains in semi-arid NE Iran was exemplarily studied with a combined approach that encompassed both alluvial fan and catchment. By using geomorphological mapping and numerical dating, fluvial aggradation followed by incision was independently identified in larger areas or in different parts of the river system ca. 95–88 ka, 40 ka, 20 ka, around/after the Pleistocene/Holocene transition and possibly ca. 2.6 ka. These could be linked with regional and over-regional paleoenvironmental data. Furthermore, large boulders on the alluvial fan suggest anthropogenic destabilisation of the catchment during the last decades. Despite strong local tectonics the fluvial dynamics was mostly controlled by paleoenvironmental changes and human activity. This indicates that despite their small size, such river systems form valuable paleoenvironmental archives in drylands where other archive types are largely missing.