Forests, pastures, and furnaces in the south-eastern Alps: the Mid-Late Holocene palaeoenvironmental record of Lake Caldonazzo

The great divide? Differences in environmental and hunter-gatherer responses to the 8.2 ka BP event between northwestern and northeastern Eurasia

The semi-arid grasslands of the Free State Province of South Africa have produced the earliest evidence of the presence of Homo sapiens in the subcontinent, together with an extensive Pleistocene palaeoenvironmental record based on fossil assemblages. However, the known Middle Stone Age (MSA) archaeological sites in the Free State are limited to a few major localities that cannot be integrated into a unitary narrative, thus hindering our understanding of human cultural evolution in the central interior of South Africa. Here we report the results of a survey of the dongas of the Modder River aimed at documenting new localities embedded within its alluvial terraces. We identified 43 previously unknown archaeological areas spanning the Late Pleistocene to Holocene based on the regional chronology, of which the majority are MSA sites. Four of the latter include artefacts in situ and thus hold potential for excavation and absolute dating by trapped-charge methods. The occurrence of a specific lithic type at six sites along the course of the river highlights a pattern in the occupation of the region during Marine Isotope Stage 5, which confirms the importance of the grasslands of the central interior for the characterisation of the spatiotemporal distribution of human groups in the open landscape during the MSA.

In recent decades, archaeological and palynological research in the Bohinj basin has mainly focused on the highlands, while research in the valley is much older and often insufficient. In order to obtain new information about the local human impact on the environment, a palynological analysis was carried out in a marsh-like environment near Srednja vas v Bohinju. The main aim of the investigation was to obtain more information about the former vegetation, economy and use of the environment.The palynological results show an early human impact on the environment (since the Eneolithic, ca. 4700 cal. BP). In the Iron Age/Roman period, the local spruce forest was replaced by pastures, which is consistent with the archaeological sites nearby. Throughout the Middle Ages, a decline in tree taxa can be observed, which could be due to continuous pastoralism and an increasing demand for iron. In the Modern Period, the landscape remained open with continuous grazing/arable farming and indirectly due to metallurgy.

Abstract A multiproxy study of a sediment sequence from a Québec peatbog characterises the rapid and significant environmental responses to changing climatic conditions from the deglaciation of the Laurentide Ice Sheet to the early Holocene period. Scotstown Bog (45°30'45.0“N, 71°11'42.0“W) is an ombrotrophic peatland on the edge of the Appalachian Uplands in southern Québec, Canada. We reconstructed its Late‐glacial and early Holocene palaeoenvironments for 14 000–6 000 cal a bp using palaeobotanical (plant macrofossil, macrocharcoal, pollen analyses), faunal (chironomid analysis), sedimentological (grain‐size analysis, sediment organic content), and geochemical (sedimentary n‐alkanes and hydrogen isotope analyses) methods. We targeted our multiproxy reconstruction on the Late‐glacial period, which provides an example of how biota can respond to profound changes in climatic and environmental conditions. A major transition occurred between 13 000 and 12 900 cal a bp, which is recorded in all palaeoecological proxies. Our reconstruction reveals two major environmental changes at this time. First, the Scotstown basin became isolated from a larger proglacial lake, as shown by sedimentological changes, sediment grain size and chironomid assemblage shift. Second, plant macrofossils and pollen influx show contemporaneous major shifts in the vegetation composition from tundra to tree‐line to closed‐canopy forested communities.

Abstract Over the vast area of present‐day Europe, the Tithonian–Berriasian transition was a time of climate aridization, which was supposedly related to the more general trend of the latest Jurassic–earliest Cretaceous cooling and restrictions in atmospheric circulation. Recent studies suggest that such conditions affected also some other paleoenvironmental processes such as monsoonal upwellings, seafloor ventilation and circulation of nutrients within the water column. In order to test this model, the uppermost Jurassic–lowermost Cretaceous sedimentary succession of the Slovenian Basin was correlated with a reference data from the Bakony Basin (Transdanubian Range, Hungary). Stratigraphic calibration was ensured by integrated stratigraphy, utilizing bio‐ (calpionellids, calcareous dinocysts) and chemostratigraphic tools (δ13C stratigraphy) as well as regional correlations of magnetic susceptibility and terrigenous input. Paleoclimate, paleoredox and paleoproductivity conditions were evaluated based on various geochemical proxies. Both the Slovenian and the Bakony basin sections were found to document late Tithonian–early Berriasian climate aridization as well as related signals of seafloor hypoxia and elevated accumulations of micronutrients. Significant geochemical contrast between the basal (lower Tithonian) radiolarites and overlying upper Tithonian–Berriasian carbonates evidences the inverse relation between the surface productivity and the amount of nutrient‐type trace metals buried in sediments. The rhythm of paleoclimatically controlled environmental changes, with relatively humid early Tithonian, arid late Tithonian–early Berriasian, and again humid late Berriasian, correlates with those estimated for Vocontian Basin (SE France) and the Sub‐Boreal domain of Western and Central Europe. This indicates that climatic stratigraphy is a useful tool for global correlation of the Jurassic/Cretaceous boundary interval.

ABSTRACT This study shows how fine and organic sediments in urban contexts can document landscape changes, anthropogenic activities and depositional processes. We focus on the transition between the late Iron Age and the Roman period in the city of Lyon (France), where an archaeological excavation conducted on Fourvière Hill aimed at understanding the evolution of a defensive site located south-west of the former Roman city. The discovery of a Gallic wall made of earth, wood and stone (murus gallicus) probably indicates the oppidum status of Lyon before the Roman colonisation. Fine-textured, organic and hydromorphic sediments containing a variety of artefacts (fine wares and amphora fragments) and abundant palaeoecological indicators (seeds, fruits, wood and charcoal fragments, pollen, shells, and parasites), were preserved at the foot of the rampart. A multidisciplinary study of these remains reveals the presence of a former hilltop pond surrounded by riparian woodlands with multi-proxy evidence of arable land or gardens, discharge from human settlements (consumption wastes, human parasites), and grazed areas (faecal inputs, animal parasites and plants tolerant to trampling). After several episodes of sediment inputs and backfill, the palaeoenvironmental record ended at the beginning of the Roman Empire, when a defensive wall was built over the site.

The palaeoenvironmental record through a Devonian-Carboniferous boundary super-monsoon lake

Research projects in the Shashe-Limpopo Basin have witnessed significant developments in the use of conceptual frameworks and multidisciplinary approaches such as electrochemical and geochemical sequencing. Accordingly, there is now data to question the widely accepted model for the evolution of Mapungubwe State (AD 1200–1300) which argues that favourable and unfavourable regional climatic weather conditions (wet and dry) lead to the rise and decline of the State. Floodplain agropastoral activities in the middle Limpopo Valley are a widely assumed hypothesis, despite the general absence of relevant chemical signatures and archaeobotanical data. This article discusses soil sequences and chemical analyses (Inductively Coupled Plasma Atomic Emission Spectroscopy and Redox Potential) to provide a palaeoenvironmental record of water regimes in relation to Mapungubwe. Findings confirm that geochemical techniques can be used to model or predict aquifer behaviour and the occurrence of groundwater. And, as such, highlighting the need for conservation planners to carefully consider integrative scientific tools to improve conservation practices of archaeological heritage and overexploitation of groundwater resources. Although more data is required, the results obtained allows researchers to begin reframing questions concerned with the links between changing water regimes and social changes, in this case relating to the decline of Mapungubwe. The understanding is important for the management and conservation of the Mapungubwe World Heritage site and surrounding landscape.

Archaeological and palaeoenvironmental investigations at Juukan 2 rockshelter have yielded new information on the ancient Aboriginal occupation of the Pilbara uplands in northwest Australia. Using multiple lines of evidence, including lithic, faunal, pollen, ancient DNA, radiocarbon dating, optically stimulated luminescence, and Bayesian chronological modelling, we show that Aboriginal people occupied the western Hamersley Plateau as early as 47,000 years ago (47 ka). Late Pleistocene populations utilised a diverse range of tool technologies, including bone points, grindstones, and flaked stone artefacts. Palaeoclimatic conditions at Juukan 2 rockshelter varied greatly over the past 47 ka, with repeated site visits by people, including during the peak hyper-arid phase of the Last Glacial Maximum (LGM) c. 21 ± 2 ka. Ancient starch analyses of the ground stone artefacts show the processing of Ipomoea (Bush Potato) from around 42 ka to the present day. Pronounced increases in the discard of stone artefacts and bone in the last 3500 years are interpreted to be the result of increased frequency of site use. A braided hair fragment dated to this period has demonstrated genetic links between the earlier rockshelter occupants and contemporary Puutu Kunti Kurrama and Pinikura peoples, who have maintained strong cultural connections to the area.

The Mülheim–Kärlich clay pit (Kärlich hereinafter) is located along the Middle Rhine Valley (MRV), about 10 km north-westward of the city of Koblenz (Fig. 1a). Owing to its > 30 m thick Quaternary sequence (Fig. 1b), it perhaps represents the most significant sedimentary profile along this entire valley reach. The sequence provides key information on long-term landscape evolution in the MRV, including successive fluvial aggradation phases related to the so-called main terraces of the Rhine and the Moselle (e.g. Boenigk and Frechen, 2006, 1998), and is also relevant for its archaeological and palaeoenvironmental record (e.g. Gaudzinski et al., 1996). Despite this importance, the quality of chronological constraints on the whole Quaternary sequence is far from being uniform (Fig. 1b). dating of three tephra layers interspersed in loess and loess-like sediments yields ages ranging from ∼ 0.47 to ∼ 0.36 Ma (Van Den Bogaard et al., 1989; Gallant et al., 2014; Fig. 1b) for the upper part of the Middle Pleistocene sequence. Whilst intermediate units can be tentatively correlated to Marine Isotope Stages (MISs) 16–12 based on biostratigraphy and on the composition of volcanic mineral assemblages (Boenigk and Frechen, 1998), there is no numerical age control on the fluvial sequence at the base (Fig. 1b). It is merely constrained by questionable palaeomagnetic data suggesting a minimum age of 0.77 Ma (all geomagnetic boundaries are from Channell et al., 2020), corresponding to the Brunhes–Matuyama boundary (e.g. Boenigk and Frechen, 1998). Altogether, the lack of a reliable chronological framework for the fluvial units is highly problematic since Rhine deposits at Kärlich were often used as a reference site for a key terrace level in the Quaternary evolution of the river, the so-called main terraces (Boenigk and Frechen, 2006). This study thus aims to fill this gap by applying electron spin resonance (ESR) dating of quartz grains from two sediment samples of the Rhine's main terrace. This new age control further refines the whole Kärlich chronostratigraphy and numerically constrains, for the first time, the aggradation time of key terrace deposits along the MRV.

Abstract Low‐lying islands in tropical regions are vulnerable to near‐term sea‐level rise and hurricane‐induced flooding, with substantial human impact. These risks motivate researchers to elucidate the processes and timescales involved in the formation, growth and stabilization of coastlines through the study of Holocene shoreline dynamics. Little Ambergris Cay (Turks and Caicos Islands) is a low‐lying carbonate island that provides a case study in the nucleation and growth of such islands. This study investigates the sedimentology and radiocarbon chronology of the island's lithified sediments to develop a model for its history. The island's lithified rim encloses a tidal swamp populated by microbial mats and mangroves. Preliminary radiocarbon data supported a long‐standing inference that the island is Holocene in age. This study integrates petrographic, sedimentological and new radiocarbon data to quantify the age of the island and develop a model for its evolution. Results indicate that the ages of most lithified sediments on the island are <1000 cal yr bp, and the generation and lithification of carbonate sediment in this system supports coastline growth of at least 5 cm/year. The lithification of anthropogenic detritus was documented, consistent with other evidence that in recent centuries the lithified rim has grown by rates up to tens of centimetres per year. A unit of mid‐Holocene age was identified and correlated with a similar unit of early transgressive aeolianite described from San Salvador, The Bahamas. It is proposed that this antecedent feature played an important role in the nucleation and formation of the modern island. Results extend an established Bahamian stratigraphic framework to the south‐western extreme of the Lucayan archipelago, and highlight the dynamism of carbonate shorelines, which should inform forward‐looking mitigation strategies to increase coastal resiliency to sea‐level rise. These results inform interpretation of the palaeoenvironmental record of carbonate environments, underscoring their geologically rapid pace of lithification.

A middle Miocene to Quaternary sedimentary and palaeoenvironmental record from the western continental shelf of South Africa

The diversity of vertebrate skeletons is often attributed to adaptations to distinct ecological factors such as diet, locomotion, and sensory environment. Although the adaptive evolution of skull, appendicular skeleton, and vertebral column is well studied in vertebrates, comprehensive investigations of all skeletal components simultaneously are rarely performed. Consequently, we know little of how modes of evolution differ among skeletal components. Here, we tested if ecological and phylogenetic effects led to distinct modes of evolution among the cranial, appendicular and vertebral regions in extant carnivoran skeletons. Using multivariate evolutionary models, we found mosaic evolution in which only the mandible, hindlimb and posterior (i.e. last thoracic and lumbar) vertebrae showed evidence of adaptation towards ecological regimes whereas the remaining skeletal components reflect clade-specific evolutionary shifts. We hypothesize that the decoupled evolution of individual skeletal components may have led to the origination of distinct adaptive zones and morphologies among extant carnivoran families that reflect phylogenetic hierarchies. Overall, our work highlights the importance of examining multiple skeletal components simultaneously in ecomorphological analyses. Ongoing work integrating the fossil and palaeoenvironmental record will further clarify deep-time drivers that govern the carnivoran diversity we see today and reveal the complexity of evolutionary processes in multicomponent systems.

Abstract A 25 m long sediment core from hypersaline Urmia Lake (north‐west Iran) was studied for the Late Quaternary depositional history and palaeoclimate variations using the abundance and compositional characteristics of Artemia faecal pellets. Sediment analysis is supported by scanning electron microscopy – energy dispersive X‐ray spectroscopy, organic and inorganic carbon content measurements, and stable isotopes (δ13C and δ18O) from faecal pellet carbonates. The imprecise chronology of the core back to 50 kyr bp is supported by ten radiocarbon ages from faecal pellets and bulk sediments. The palaeoenvironmental record is subdivided into four periods: (i) During much of Marine Isotope Stage 3, a period of lake level lowering is characterized by a decreasing amount of faecal pellets, and an increasing amount of coated grains, sulphate minerals and reworked shell fragments. (ii) During late Marine Isotope Stage 3 and early Marine Isotope Stage 2 a lake level lowstand and a lake floor exposure is interpreted based on the relatively low abundance of pellets, which are multicoloured and appear together with volcanic lithics and rounded sulphate minerals. (iii) During late Marine Isotope Stage 2 the record is devoid of pellets but dominated by large sulphate crystals suggesting a prolonged low lake level. (iv) During Marine Isotope Stage 1 a relative lake level highstand is rapidly established with sediments that are highly abundant in fresh pellets. The modern lake level lowstand is represented by a salt crust. The δ13C and δ18O records measured from faecal pellet carbonates suggest a link with the precipitation versus evaporation balance in the lake over time. From bottom to top the linear trend towards more negative delta values illustrates the increasing amount of precipitation arriving at the lake from the Late Pleistocene to the Holocene. Two prominent isotope minima during the Late Pleistocene and one prominent minimum in the early Holocene mark relative high lake levels, which can also be linked to Lake Van in Turkey.

Abstract. Anthropogenic activities have exerted strong influence on ecosystems worldwide, particularly since 1950 CE. The local impact of past human activities often started much earlier and deserves detailed study. Here, we present an environmental record from a 278 cm long sedimentary core from Lake Höglwörth (Bavaria, Germany). Sedimentological and geochemical parameters indicate that the organic-rich bottom sediments of the record consist of peat that formed prior to 870-160+140 CE, when lake sediments started to accumulate. After 870-160+140 CE, distinct shifts in lithology, elemental composition, and the biological record are visible and are interpreted to result from the construction of a monastery on the lake peninsula in 1125 CE and/or the damming of the lake. From 1120±120 to 1240-120+110 CE, the lake environment was relatively stable. This period was followed by enhanced deforestation that led to a more open landscape and soil erosion, visible in increased allochthonous input from 1240-120+110 to 1380-110+90 CE. This was accompanied by high aquatic productivity and bottom or interstitial water anoxia from 1310-120+100 to 1470-100+90 CE, possibly triggered by increased nutrient availability. Enhanced allochthonous input and a substantial shift in the aquatic community can be assigned to the construction of a flour mill and related rerouting of a small creek in 1701 CE. High aquatic productivity and bottom or interstitial water anoxia after 1960±10 CE correspond to recent eutrophication resulting from accelerated local anthropogenic activities. The sedimentary record from Lake Höglwörth exemplarily demonstrates that anthropogenic activities have had substantial environmental impacts on aquatic environments during the past millennium.

Late Quaternary climatic inferences from southern Patagonia (∼53°S): A holistic palaeoecological approach to tracking the behaviour of the southern westerly winds

Abstract Upper Palaeolithic archaeological sites in the Basque Country have been excavated for over a century. They have yielded a rich palaeoenvironmental record with zoological and botanical remains that have been obtained in stratigraphic series dated precisely by radiocarbon. This information reveals cyclical environmental changes from climates similar to today to drier and extremely cold conditions, when species in current boreal biomes and others now extinct but with similar ecological preferences were present in the region. Moreover, the archaeological sites have provided high-resolution information about the resilience mechanisms of the communities of our own human species. This information allows us to increase the corpus of palaeoclimate data regarding the Marine Isotopic Stage (MIS) 2 and MIS 3 for a critical region within the human population of Eurasia. The aim of this paper is to show how an extraordinary capacity for adaptation to drastic climate changes Upper Palaeolithic hunter–gatherer societies displayed, even though their subsistence depended on biotic resources that alter rapidly.

Abstract. The Late Pliensbachian Event (LPE), in the Early Jurassic, is associated with a perturbation in the global carbon cycle (positive carbon isotope excursion (CIE) of ∼2 ‰), cooling of ∼5 ∘C, and the deposition of widespread regressive facies. Cooling during the late Pliensbachian has been linked to enhanced organic matter burial and/or disruption of thermohaline ocean circulation due to a sea level lowstand of at least regional extent. Orbital forcing had a strong influence on the Pliensbachian environments and recent studies show that the terrestrial realm and the marine realm in and around the Cardigan Bay Basin, UK, were strongly influenced by orbital climate forcing. In the present study we build on the previously published data for long eccentricity cycle E459 ± 1 and extend the palaeoenvironmental record to include E458 ± 1. We explore the environmental and depositional changes on orbital timescales for the Llanbedr (Mochras Farm) core during the onset of the LPE. Clay mineralogy, X-ray fluorescence (XRF) elemental analysis, isotope ratio mass spectrometry, and palynology are combined to resolve systematic changes in erosion, weathering, fire, grain size, and riverine influx. Our results indicate distinctively different environments before and after the onset of the LPE positive CIE and show increased physical erosion relative to chemical weathering. We also identify five swings in the climate, in tandem with the 405 kyr eccentricity minima and maxima. Eccentricity maxima are linked to precessionally repeated occurrences of a semi-arid monsoonal climate with high fire activity and relatively coarser sediment from terrestrial runoff. In contrast, 405 kyr minima in the Mochras core are linked to a more persistent, annually wet climate, low fire activity, and relatively finer-grained deposits across multiple precession cycles. The onset of the LPE positive CIE did not impact the expression of the 405 kyr cycle in the proxy records; however, during the second pulse of heavier carbon (13C) enrichment, the clay minerals record a change from dominant chemical weathering to dominant physical erosion.

Ethnographic observations suggest that Indigenous peoples employed a distinct regime of frequent, low-intensity fires in the Australian landscape in the past. However, the timing of this behaviour and its ecological impact remain uncertain. Here, we present detailed analysis of charcoal, including a novel measure of fire severity using Fourier transform infrared (FTIR) spectroscopy, at a site in eastern Australia that spans the last two glacial/interglacial transitions between 135–104 ka and 18–0.5 ka BP (broadly equivalent to Marine Isotope Stage (MIS) 6-5 and 2-1, respectively). The accumulation of charcoal and vegetation composition was similar across both periods, correlating closely with Antarctic ice core records, and suggesting that climate is the main driver of fire regimes. Fire severity was lower over the past 18,000 years compared to the penultimate glacial/interglacial period and suggests increasing anthropogenic influence over the landscape during this time. Together with local archaeological records, our data therefore imply that Indigenous peoples have been undertaking cultural burning since the beginning of the Holocene, and potentially the end of the Last Glacial Maximum. We highlight the fact that this signal is not easily discernible in the other proxies examined, including widely used charcoal techniques, and propose that any anthropogenic signal will be subtle in the palaeo-environmental record. While early Indigenous people’s reasons for landscape burning were different from those today, our findings nonetheless suggest that the current land management directions are based on a substantive history and could result in a reduction in extreme fire events.