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Highlights: • A single Saksunarvatn Ash layer was detected in two varved lake cores from N-Germany. • The ash layers in the two cores are dated to 10,282 ± 45 and 10,264 ± 24 cal. BP. • Palynological and geochemical analysis were conducted in proximity of the ash layers. • Environmental disturbance, possibly linked to volcanism, predates the ash fallout. • Evidence for a ca. 15-year-long cooling is recognizable after tephra deposition. Abstract Estimating the environmental and societal impact of recent volcanic eruptions is a task aided by direct measurements and historical sources. Beyond the reach of first-hand accounts, our understanding of pre-historic volcanism is often hindered by dating uncertainties inherent to geological archives. Here, we minimize dating errors by analyzing the annually laminated sequences of two Central European lakes, Poggensee and Woseriner See. We focus on environmental transformations that occurred in the decades preceding and following the deposition of the Icelandic Saksunarvatn tephra, dated between ca. 10,300 and 10,200 cal. BP. As a first result, we provide two new independent age determinations for the ash layer detected in both sequences. Our estimates (10,264 ± 24 cal. BP at Poggensee and 10,282 ± 45 cal. BP at Woseriner See) place the age of this tephra deposit closer to Greenland estimates than to continental ones, possibly reducing the chronological gap between the multiple fallout events that characterize the Saksunarvatn Ash. A high resolution palaeoenvironmental characterization was carried out via pollen, thin sections and geochemical analysis. Both sequences show traces of a contemporaneous disturbance event dated to ca. 18 years before tephra deposition. In addition, environmental impact compatible with a cooling event is discernible for ca. 15 years following tephra deposition. While independent climate mechanisms can be responsible for the observed trends, we explicitly focus on exploring volcanic eruptions as a possible leading driver. A consistent agreement across all proxies is lacking in the pre-tephra record, yet sulfur enrichment and acidification processes allow us to suggest volcanism as a plausible trigger. Combined with the post-tephra cooling, the two sedimentary records depict a possible scenario of multi-decadal, continuous volcanic impact.

International audience; Wood was a crucial resource for prehistoric societies, for instance, as timber for house construction and as fuel. In the case of the exceptionally large Chalcolithic Tripolye ‘mega-sites’ in central Ukraine, thousands of burnt buildings, indicating huge population agglomerations, hint at such a massive use of wood that it raises questions about the carrying capacity of the sensitive forest-steppe environment. In this contribution, we investigate the wood demand for the mega-site of Maidanetske (3990–3640 BCE), as reconstructed based on wood charcoal data, wood imprints on daub and the archaeo-magnetometry-based settlement plan. We developed a regional-scale model with a fuzzy approach and applied it in order to simulate the potential distribution and extent of woodlands before and after Chalcolithic occupation. The model is based upon the reconstructed ancient land surface, soil information derived from cores and the potential natural woodland cover reconstructed based on the requirements of the prevailing ancient tree species. Landscape scenarios derived from the model are contrasted and cross-checked with the archaeological empirical data. We aim to understand whether the demand for wood triggered the site development. Did deforestation and consequent soil degradation and lack of resources initiate the site’s abandonment? Or, alternatively, did the inhabitants develop sustainable woodland management strategies? Starting from the case study of Maidanetske, this study provides estimates of the extent of human impact on both carrying capacity and landscape transformations in the sensitive transitional forest-steppe environment. Overall, the results indicate that the inhabitants of the Chalcolithic site did not suffer from a significant shortage in the wood resource at any time of inhabitation in the contexts of the different scenarios provided by the model. An exception is given by the phase of maximum house construction and population within a scenario of dry climatic conditions.

Over the past decades multi-element analyses have become increasingly important for archaeological and geoarchaeological research. In particular the recent expansion in availability of portable ed-XRF (p-ed-XRF) devices has allowed for the fast acquisition of large data sets. In the presented paper, we evaluate the quantitative measurement capability of a p-ed-XRF device through comparison with wd-XRF. Sampling, drying, and homogenization (sieving In a case study, we measured the elemental contents of the archaeo-sediment-sequence fill of a trench of a ca. 7300 year old Linear Pottery house at the site of Vráble-Ve'lke Lehemby, in southeastern -Slovakia. Based on a model applied at the nearby Bronze Age settlement mound of Fidvár, the P content of the archaeo-sediment was considered as a proxy of palaeo-demography. However, the measured P contents were much too small to reflect the metabolism of a reasonable number of inhabitants. Therefore, in addition to the possibilities of shorter than expected duration of house occupation and incomplete garbage deposition within the ditches, the post-depositional settlement history is considered in detail. Furthermore, bio-cycling by plants during different subsequent phases of Holocene landscape development (forested, agricultural field use) has not been considered extensively in interpretations of the archaeological record so far, but might have had a considerable influence on the shallow buried archaeological record. A reconsideration of the interpretation of the geochemical record from a nearby Bronze Age site (Fidvár) is thus suggested.

The environmental history since the onset of agriculture was reconstructed from sediments and soils in the catchment area of Lake Belau (Schleswig-Holstein, northern Germany). The established chronologies are based on varve counts, radiocarbon data, embedded Icelandic tephra (lake sediments), radiocarbon dates, and embedded artifacts (slope deposits). Neolithic land use triggered small-scale erosion. Lake trophic indicators and pollen data clearly reflect the onset of agriculture and the middle Neolithic expansion of agricultural activity. Despite numerous archaeological findings, less intensive field use and no soil erosion occurred during the older and younger Bronze Age. Perhaps, animal husbandry was more important than cereal cultivation. Between 2000 and 500 cal. bc, Aeolian input from a distant source can be observed. During the late Bronze Age and Pre-Roman Iron Age, intensified field use enabled severe soil erosion (gullies c. 200 cal. bc). The degradation of soils started in this period, influenced by excessive land use, climatic variability, and/or the reduction in Aeolian deposition. The Roman Iron Age and Migration Period were phases of reduced human impact and soil formation. During medieval times, the intensity of field use increased again and another phase of soil erosion (gully in the 14th century, probably reflecting the ‘Magdalenenflut’ 1342) and soil degradation started. After the late medieval crisis caused by the ‘black death’ and several armed conflicts, another increase in soil erosion may reflect the rearrangement of estates (18th−19th century) and introduction of industrial agriculture (20th century). A recurrence of high-intensity erosion events is indicated at c. 1540, 1710, and probably 1939 ad. Whereas the lake trophic status is influenced by human impact on the lake catchment, wetter and warmer climatic phases are reflected in increased carbonate precipitation modulated by solar activity, human impact, and the long-term evolution of vegetation and soils in the lake catchment.

International audience; The annually laminated record of Lake Belau offers an exceptional opportunity to investigate with high temporal resolution Holocene environmental change, aspects of climate history and human impact on the landscape. A new chronology based on varve counts, 14C-datings and heavy metal history has been established, covering the last 9400 years. Based on multiple varve counting on two core sequences, the easily countable laminated section spans about 7850 varve years (modelled age range c. 9430 to 1630 cal. BP). Not all of the record is of the same quality but approximately 69% of the varves sequence is classified to be of high quality and only c. 5% of low quality. The new chronology suggests dates generally c. 260 years older than previously assumed for the laminated section of the record. The implications for the vegetation and land-use history of the region as well as revised datings for pollen stratigraphical events are discussed. Tephra analysis allowed the identification of several cryptotephra layers. New dates for volcanic eruptions are presented for the Lairg B event (c. 6848 cal. BP, 2s range 6930–6713 cal. BP), the Hekla 4 event (c. 4396 cal. BP, 2s range 4417–4266 cal. BP), and Hekla 3 eruption (c. 3095 cal. BP, 2s range 3120–3068 cal. BP).

The annually laminated record of Lake Belau offers an exceptional opportunity to investigate with high temporal resolution Holocene environmental change, aspects of climate history and human impact on the landscape. A new chronology based on varve counts, 14C-datings and heavy metal history has been established, covering the last 9400 years. Based on multiple varve counting on two core sequences, the easily countable laminated section spans about 7850 varve years (modelled age range c. 9430 to 1630 cal. BP). Not all of the record is of the same quality but approximately 69% of the varves sequence is classified to be of high quality and only c. 5% of low quality. The new chronology suggests dates generally c. 260 years older than previously assumed for the laminated section of the record. The implications for the vegetation and land-use history of the region as well as revised datings for pollen stratigraphical events are discussed. Tephra analysis allowed the identification of several cryptotephra layers. New dates for volcanic eruptions are presented for the Lairg B event ( c. 6848 cal. BP, 2s range 6930–6713 cal. BP), the Hekla 4 event ( c. 4396 cal. BP, 2s range 4417–4266 cal. BP), and Hekla 3 eruption ( c. 3095 cal. BP, 2s range 3120–3068 cal. BP).