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In recent years, much evidence has been presented on the 4.2 ka event. A review of 317 palaeoclimate papers shows that dry conditions were common during the event, especially from Eastern Mediterranean to India. The 4.2 ka event was not, however, a global drought event. Wet conditions were reported especially for central/northern Europe and sub-Saharan Africa. The 4.2 ka event is typically characterized either as short (4.2–4.0 ka) or long (4.4–3.8 ka) episode, possibly developing over an extended interval of time, in keeping with the North Atlantic forcing and correlating with the Bond 3 event of ice-rafted debris. This forcing is understood to drive a southward migration of the Inter-Tropical Convergence Zone (ITCZ), resulting in decreased rainfall over most of the Asian monsoon region, with possibility that an interplay of El Niño–Southern Oscillation (ENSO) and North Atlantic Oscillation (NAO) has modulated the global circulation. Cold conditions were also reported but less frequently, in comparison to other Bond events such as the 8.2 ka event, Dark Ages Cold Period and Little Ice Age. Some high-resolution records show a double peak structure of which two anomalies are tree-ring dated to 4.14–4.05 ka and 3.97 ka. Accurately and precisely dated high-resolution records indicative of various climatic variables, especially outside of the traditional study region (Mediterranean–Middle East–India–China), including reconstructions of the ENSO and NAO histories and ITCZ migrations, are crucially needed for rigorous examination of the global scale characteristics of the 4.2 ka event and its forcings. Such research seems to be just beginning. [ABSTRACT FROM AUTHOR]

This paper examines the hypothesis that Waun Mawn in West Wales provided the bluestone monoliths that were used at Stonehenge. Some archaeologists believe that the site supports the last remains of a giant stone circle or 'Proto Stonehenge' which was dismantled and transported to Salisbury Plain around 5000 years ago. It was claimed, after three excavation seasons at Waun Mawn in 2017, 2018 and 2021, that there is firm evidence of some standing stones which were later removed or broken up, but it has still not been demonstrated that there ever was a small stone circle here, let alone a 'giant' one. Furthermore, there have been no control studies in the neighbourhood which might demonstrate that the speculative feature has any unique characteristics. There is nothing at Waun Mawn to link this site in any way to Stonehenge, and this is confirmed by recent cited research. No evidence has been brought forward in support of the claim that 'this was one of the great religious and political centres of Neolithic Britain'. It is concluded that at Waun Mawn and elsewhere in West Wales there has been substantial 'interpretative inflation' driven by the desire to demonstrate a Stonehenge connection. [ABSTRACT FROM AUTHOR]

This special volume considers major recent changes in southern South American animal communities. Eleven papers consider megafauna, pinnipeds, marine mammals, small terrestrial mammals and birds and are grouped under four sub-headings: (1) Isotopic insights into guanaco populations; (2) Historical sources and marine ecosystem change; (3) Changes in small mammal communities and human impacts; and (4) megafaunal extinction, domestication, avifauna and recent interactions with humans. Although some of these contributions include changes that occurred earlier in the Holocene, many highlight a current decrease in the taxonomic diversity of communities and ecosystems in different environments, which are likely to have been caused by modern human activities. The Anthropocene concept is seen as providing a useful framework for understanding and mitigation of such adverse human impacts. [ABSTRACT FROM AUTHOR]

We describe the career of John Birks as a pioneering scientist who has, over a career spanning five decades, transformed palaeoecology from a largely descriptive to a rigorous quantitative science relevant to contemporary questions in ecology and environmental change. We review his influence on students and colleagues not only at Cambridge and Bergen Universities, his places of primary employment, but also on individuals and research groups in Europe and North America. We also introduce the collection of papers that we have assembled in his honour. The papers are written by his former students and close colleagues and span many of the areas of palaeoecology to which John himself has made major contributions. These include the relationship between ecology and palaeoecology, late-glacial and Holocene palaeoecology, ecological succession, climate change and vegetation history, the role of palaeoecological techniques in reconstructing and understanding the impact of human activity on terrestrial and freshwater ecosystems and numerical analysis of multivariate palaeoecological data. [ABSTRACT FROM AUTHOR]

The study of disarticulated ossicles of recent sea cucumbers from Campos Basin, Rio de Janeiro, Brazil, from various Holocene strata, obtained by micropaleontological methods, resulted in the identification of at least eight holothurian taxa, belonging to the five of the seven orders of Holothuroidea: Apodida (Synaptidae, Chiridotidae), Dendrochirotida (Psolidae and Cucumariidae), Holothuriida (Holothuria), and Molpadiida (Molpadiidae, Eupyrgidae). Our paper endorses the importance of studies of recent fauna based on isolated ossicles for taxonomy, biostratigraphy, and ecology. This study represents the first effort at the study of recent fauna of sea cucumbers based on the analysis of preserved ossicles in marine sediments. [ABSTRACT FROM AUTHOR]

The paper presents isolation basin stratigraphy in bottom sediments from nine lakes in the Teriberka area on the Kola Peninsula, northwestern Russia. Isolation contacts in these basins, identified from lithological and diatom analysis, were used together with 25 radiocarbon dates, to construct a relative sea-level (RSL) curve for the Holocene. Records of marine water re-influx were found in the sediment sequence from one lake, located at c. 17 m a.s.l. The re-influx of marine water seems to be caused by the mid-Holocene (Tapes) transgression and tsunami event. The RSL curve indicates several phases in the postglacial evolution of the Kola coast. An early phase of rapid sea-level fall of c. 32 m around 11,500 cal yr BP, at a rate of c. 40 mm per year, corresponds to glacio-isostatically induced emergence following deglaciation at the Younger Dryas and beginning of the Holocene. In the time interval between c. 11,000 and 7600 cal yr BP, either a stillstand or a slight rise in relative sea level, cresting at about 21 m a.s.l., is suggested in the Teriberka area. This is followed, after c. 7300 cal yr BP to the present day, by a slow glacioisostatic emergence with an average rate of about 2–3 mm per year. [ABSTRACT FROM AUTHOR]

From the early Holocene onward, the Indian Subcontinent has accommodated a range of diverse human cultures and associated ecological adaptations and lifestyles. Around 10 kyrs ago, the Subcontinent has witnessed the development of later Mesolithic hunter-gatherers and their subsequent regional transitions to pastoralist (Neolithic) and agricultural (Chalcolithic) lifeways. The Holocene climate records reveal discrepancies in the timing and duration of climatic events, which can be attributed to a vast geographic isolation, the influence of height, elevation, and local climatic conditions. These changing climatic patterns including the development of a geographically variable monsoon directly impacted these various cultures including the Harappans and their contemporaries as well as younger Historical and Medieval empires across India, at various levels. In some regions, environmental changes led to uneven cultural transitions, geographic migrations, and the development of regionally-distinct material cultures along with establishment of sedentary life-ways. This paper attempts to present a review broadly correlating general climatic patterns throughout the Holocene period of India with regional cultural dynamics. All geomorphic-climatic zones of the Subcontinent showed strong inter-proxy coherence between 9 and 5 kyrs in response to increased precipitation. After this warming period ends, we see a moderate dry period as a result of a weakening monsoon and an overall tendency toward aridity throughout all zones (after 4 kyrs). The temporal variation of human habitation and respective adaptive responses suggest broad linkages to the varying climatic and physiographic features at a regional scale. Learning how this shaped human eco-dynamics in the past can help us expand our understanding of human history and implement lessons for the present as well as the future. [ABSTRACT FROM AUTHOR]

Cabo Verde remained uninhabited until 1460 CE, when European sailors founded a settlement in Santiago, and soon after in Fogo island. The degree to which different island ecosystems in Cabo Verde have been transformed by humans remains uncertain because of a scarcity of historical information and archaeological evidence. Disentangling these processes from natural ones is complicated in islands with a history of volcanic impacts and other natural hazards. In this paper, we apply microfossil (pollen, non-pollen palynomorphs and phytoliths) and sedimentological analyses (granulometry, X-ray diffraction, loss on ignition and tephrostratigraphy) to a 2-m sediment sequence deposited in a scoria cone from 4100 cal year BP (calibrated years before 1950 CE) to the present. The organic-rich basal sediments indicate that between 4100 and 2600 cal year BP the pre-settlement landscape of Fogo was an open grassland, where fire was infrequent and/or small-scale. An increase in volcanic glass deposition after 2600 cal year BP, peaking ca. 1200 cal year BP, suggests that there was a progressive activation of Fogo's volcanic activity, contemporaneous with increased fire frequency and erosion pulses, but with little impact on local grassland vegetation. While dating uncertainty is high, the first evidence of intensive local land use by early settlers was in the form of cultivation of Zea mays, abundant spores of coprophilous fungi (i.e. Sporormiella), and peaks in charcoal concentrations between 800 and 400 cal year BP. This was followed by large increases in pollen from pigeon pea (Cajanus), a diverse array of exotic trees (Cupressus, Grevillea), and invasive shrubs (Lantana). The introduction of these taxa is part of recent human effort to 'tame' this steep, dry and hazardous island by reducing erosion and providing firewood. An important outcome of these efforts, however, is a loss of fragile native biodiversity. [ABSTRACT FROM AUTHOR]

Most studies on the geomorphological evolution of the Holocene from the Ebro depression (NE Spain) are focused on the period up to the Roman Epoch (218 BC–476 AD) while some references to medieval (476 AD–15th century) deposits are also occasionally dated. This paper focuses on the establishment of aggradation units on the valley bottoms and slopes of the Ebro depression after 1400 BP, their origin, comparison with other areas, and relationship with global paleoenvironmental changes. These units were produced after the incision phase that marked the end of the large Holocene accumulation (unit H1) around 1400 BP (at the end of the Late Roman Epoch). Morphosedimentary records enable us to establish three aggradation units during the last 1400 years: unit H2 (ca. 1400–650 cal BP); unit H3 – with two H3A subunits (ca. 650–500 cal BP) and H3B (ca. 500–320 cal BP); and the H4 unit (after 320 cal BP). These units are organized following five types of aggradation/incision arrangements with differing complexities. There are also connections among these units and two slope stages in the region. Finally, the genetic relationships between these units and global paleoenvironmental changes are shown (LALIA, MCA, and LIA) and related to anthropic activity. This contribution is the first detailed and systematic approach to the study of morphosedimentary units and sedimentary arrangements during the Recent Holocene in the Mediterranean area. [ABSTRACT FROM AUTHOR]

When Ötzi, the Iceman, was found in a gully in the Tisenjoch pass in the Tyrolean Alps in 1991, he was a huge surprise for the archaeological community. The lead initial investigator of the find argued that it was unique, preserved by serendipitous circumstances. It was hypothesised that the mummy with associated artefacts had been quickly covered by glacier ice and stayed buried until the melt-out in 1991. It is now more than 30 years since Ötzi appeared. In this paper, we take a closer look at how the find can be understood today, benefitting from increased knowledge gained from more than two decades of investigations of other glacial archaeological sites, and from previous palaeo-biological investigations of the find assemblage. In the light of radiocarbon dates from the gully and new glaciological evidence regarding mass balance, it is likely that Ötzi was not permanently buried in ice immediately after his death, but that the gully where he lay was repeatedly exposed over the next 1500 years. We discuss the nature of the ice covering the site, which is commonly described as a basally sliding glacier. Based on the available evidence, this ice is better understood as a non-moving, stationary field of snow and ice, frozen to the bedrock. The damaged artefacts found with Ötzi were probably broken by typical postdepositional processes on glacial archaeological sites, and not, as previously claimed, during conflict prior to Ötzi's flight from the valley below. [ABSTRACT FROM AUTHOR]

This paper evaluates risk-oriented frameworks for explaining environmental, social, and economic changes faced by fishing and herding communities in the Turkana Basin during and after the African Humid Period (AHP, 15–5 ka). The orbitally-forced AHP created moist conditions, high lake levels, and unusual hydrological connections across much of northern and eastern Africa. As arid conditions set in and rainfall decreased between 5.3 and 3.9 ka in eastern Africa, Lake Turkana (NW Kenya) shrank dramatically. Shoreline retreat coincided with an expansion of open plains, creating new ecological conditions and potential opportunities for early herders in the basin. In this changing landscape, economies shifted from food procurement (fishing/hunting aquatic resources) to food production (herding), likely through both in-migration by pastoralists and adoption of herding by local fishers. Early pastoralists also built at least seven megalithic pillar sites that served as communal cemeteries during this time. Recent research has shown that local environmental dynamics – both during and after the AHP – were complex, demanding a more careful interrogation of the notion that post-AHP life entailed new and/or heightened risks. Risk-buffering strategies might include mobility, diversification, physical storage, and exchange. Archaeologists working around Lake Turkana have proposed that economic shifts from fishing to pastoralism entailed increased mobility as a risk-buffering strategy to deal with aridity and resource unpredictability, and that pillar sites – as fixed landmarks in an unstable landscape – provided settings for congregation and exchange amongst increasingly mobile herding communities. However, recent research has shown that local environmental dynamics in the Lake Turkana basin – both during and after the AHP – were more complex than previously thought, necessitating re-evaluation of the notion that post-AHP life entailed new and/or heightened risks. Here, we explore risk buffering strategies (e.g. mobility, diversification, physical storage and/or exchange) as only one category of potential explanation for the new social practices observed in the region at this time. Gauging their applicability requires us to (a) assess the spatial mobility of communities and individuals interred at pillar sites; (b) evaluate whether and how mobility strategies may have changed as pastoralism supplanted fishing; and (c) examine alternative explanations for social and economic changes. [ABSTRACT FROM AUTHOR]

In 2015, the journal Science invited me to comment on the start of anthropogenic change. That request was likely related to the fact that the Anthropocene Working Group (AWG) of the International Commission of Stratigraphy was thinking of choosing a formal start date for the Anthropocene at or after 1950. Joined by three co-authors (Ruddiman et al., 2015), we emphasized the many near-global anthropogenic changes that preceded 1950 by centuries to millennia. Early in 2018, Progress in Physical Geography (PiPG) published a more extended critique of mine regarding this possible AWG action. I noted three flaws in choosing 1950 as the formal start date. In response to this challenge, the AWG recently submitted two draft papers to PiPG, one rebutting my 2018 paper (Zalasiewicz et al.), and one supporting and extending it (Edgeworth et al.). The first part of this reply elaborates on the flaws cited in my 2018 PiPG paper, incorporating comments from Edgeworth et al. The second part addresses the criticisms in Zalasiewicz et al. [ABSTRACT FROM AUTHOR]

This paper presents new data derived from pollen, starch and radiocarbon samples that were collected from six Aboriginal earth (oven) mounds and middens on the Calperum and Pike floodplains, Murray-Darling Basin (MDB), South Australia (SA). Analyses of these samples were undertaken in order to enhance our understanding about the Holocene lifeways of Aboriginal people living in this region. The results from these analyses, combined with published data about the mounds’ contents, relevant ethno-historical information and climate data, allow us to infer that Aboriginal people adopted, in this region, an innovative food production system about 3800 years ago. Further, we argue that the timing of the change suggests this was in response to adverse El Niño Southern Oscillation (ENSO) related weather patterns and consequently fluctuations in both terrestrial and aquatic food resources. [ABSTRACT FROM AUTHOR]

Quantifying the relative influences of anthropogenic activities and climate change on soil erosion and deposition during the Holocene, when both forces have been interacting is a complex problem. Analysis of long-term patterns in soil erosion and lake deposition in a basin can provide the basis for untangling the complexities of climate and anthropogenic forcings. In this paper, sedimentary sequences from Xingyun Lake are compared with simulated soil erosion rates in the basin to explore the relationship between river basin soil erosion and lake deposition during the Holocene in Yunnan, China. Modern soil erosion rates are calculated using RUSLE, while Holocene soil erosion rates are estimated using modern rates with reconstructed precipitation and vegetation cover sequences. Through this investigation, we found the following results. First, Holocene vegetation in the lake basin was mainly affected by climate change, and the vegetation experienced the same pattern of changes as the climate. Soil erosion and lake deposition rates, along with changes to vegetation cover, were synchronous with precipitation trends during the Holocene. Second, soil erosion and lake deposition have been exacerbated by human activities, such as deforestation and land reclamation in the Xingyun Lake basin. Finally, this study provides new insights into the effects by anthropogenic impacts and climate forcing on the processes of soil erosion and lake deposition on the millennium scale. [ABSTRACT FROM AUTHOR]

This paper provides another look at the response of the Asian summer monsoon (ASM) to insolation forcing and oceanic feedback during the Holocene, using a fully coupled general circulation ocean–atmosphere model forced by Earth’s orbital variations. The model results revealed a recurrent circumglobal teleconnection (CGT) pattern in the summertime (June–July–August) mid-latitude circulation of the Northern Hemisphere during the Holocene. The CGT index showed a decreasing trend before ~5 ka BP and a slight increasing trend afterwards, affected by the combined effects of summer insolation, Indian summer monsoon (ISM), North Atlantic and Indian Ocean–western Pacific Ocean sea surface temperature (SST). The CGT showed a close relationship with ASM precipitation and surface air temperature during the Holocene and, therefore, could act as a bridge linking the ASM to insolation, high-latitude forcing (North Atlantic SST), and low-latitude forcing (tropical Ocean SST). We emphasize that the mid-latitude atmospheric circulation has been a key factor for the evolution of the ASM during the Holocene. In addition, the CGT provides a viable explanation for the out-of-phase relationship in the moisture evolution but an in-phase relationship in the speleothem δ18O between arid central Asia and the ISM region during the Holocene. [ABSTRACT FROM AUTHOR]

Peatlands store massive amounts of organic carbon, but the fate of this carbon remains unclear as global climate continues to warm. The age of peatland inception and the main drivers of peat initiation are one of the most important issues in Holocene paleoecology, especially for the numerous but under investigated peatlands in European Russia. This paper introduces new peatland initiation ages for 44 mires in three areas located in the central part of European Russia within the Polesie landscape belt. This region is characterised by waterlogged sandy plains and flat surface topography. Phases of peatland initiation were compared with Holocene fire regime derived from macro-charcoal data as well as with regional climatic reconstructions. We found that peat inception in the region started around 12,000 cal yr BP, but the most active phases of peatland initiation took place during the periods 8500–7500, 7000–6000, 5300–5800, 4000–3500 and 1700–1200 cal yr BP. Expect for rapid peat growth during the early Holocene, peatland initiation mostly coincided with warm climatic periods and increased fire frequency. Forest soil paludification in poorly drained Polesie landscapes was presumably enhanced by reduced evapotranspiration and changes in water balance due to disturbance of forest cover after wildfires. We expect that rising air temperature in the current century will cause higher fire frequencies and may encourage waterlogging of forests and ecosystem transformation. [ABSTRACT FROM AUTHOR]

This paper presents new multi-proxy records of the Holocene environmental and climatic changes in the Western Caucasus revealed from a continuous sediment sequence from mountainous Lake Khuko (Caucasus State Natural Biospheric Reserve, 1744 m a.s.l.). Palaeoecological analyses of a sediment core for grain size, magnetic susceptibility, loss on ignition, and pollen allowed us to determine five principal climatic phases with several subphases since 10.5 ka BP. The age model is based on seven accelerator mass spectrometry 14C dates, supplemented by 210Pb data for the uppermost part of the sediment core. Warm periods (10.5–6.7, 6.7–5.5, 3.5–2.4, 0.8–0.5 ka BP) were characterized by high biological productivity in the lake as indicated by high organic matter content and expansion of forests, typical of modern low and middle mountain zones, as indicated by the increase in abundance of Quercus, Ulmus, Corylus, and Tilia in the pollen assemblages. Cold periods (5.5–3.5, 2.4–0.8, and 0.5 ka BP–present) are marked by a consistent decrease in organic matter content in lake deposits and possibly higher intensity of the catchment erosion. The changes in pollen assemblages (for instance peaks of Abies, Picea, and Pinus) suggested a potential elevational decline in the boundaries of vegetation belts and expansion of high-altitude woodlands. Abrupt changes in the lake ecosystem were identified between 4.2 and 3.5 ka cal BP marked by a short-term variation in sediment regime shown by variation in organic matter content, magnetic susceptibility values, and sediment grain size. This was probably caused by climatic fluctuations in the Western Caucasus region as a result of complex shifts in the ocean-atmosphere system during the 4.2 ka event. Overall, the first Holocene multi-proxy continuous lake sediment record provides new insights into the climate history in the Western Caucasus. [ABSTRACT FROM AUTHOR]

The Holocene is recognised as a period through which a number of climatic fluctuations and environmental stresses occur—associated with intensifying El Niño–Southern Oscillation (ENSO) climatic conditions from c. 5000 years—contemporaneous with technological and social changes in Australian Aboriginal lifeways. In the Kimberley region of northwest Western Australia, human responses to ENSO driven climate change are most evident archaeologically in technological transformations observed in lithic records, with little research on changes in plant use during this time. Using nine archaeological sites across the Kimberley, this paper synthesises previously published macrobotanical data (Carpenter's Gap 1, Moonggaroonggoo, Mount Behn, and Riwi), reports unpublished data (Brooking Gorge 1, Djuru, and Wandjina rockshelter), and presents results of sites reanalysed for this study (Widgingarri Shelters 1 and 2) to develop a picture of localised and regional patterns of plant use during the Holocene. We conclude that food plants associated with monsoon rainforest environments dominate both mid- and late Holocene macrobotanical records and, although monsoon rainforest likely retreated to some extent because of decreased precipitation during the late Holocene, no human responses associated with ENSO driven climate change occurred in relation to human uses of plants. [ABSTRACT FROM AUTHOR]

This paper presents the results of pollen, diatom, charcoal, and sediment analyses from Lake Bol'shoye Zavetnoye, situated between the Gulf of Finland and Lake Ladoga on the Karelian Isthmus, north-western Russia. The main goal is to contribute to the discussion of Neolithic land use in north-eastern Europe. The article aims to answer questions related to Stone Age hunter-gatherer economy, ecology, and anthropogenic environmental impact through a comprehensive combination of multiple types of palaeoecological data and archaeological material. According to diatom data, Lake Bol'shoye Zavetnoye was influenced by the water level oscillations of Ancient Lake Ladoga during much of the Holocene. Intensified human activity and prolonged human occupation become visible in the Lake Bol'shoye Zavetnoye pollen data between 4480 BC and 3250 BC. During the final centuries of the Stone Age, a new phase of land use began, as several anthropogenic indicators, such as Triticum, Cannabis, and Plantago lanceolata appear in the pollen data and a decrease in Pinus values is recorded. In general, the results indicate that socio-cultural transformations could have taken place already from the mid-5th millennium BC onwards, including new ways of utilizing the environment, perhaps also in the field of subsistence, even though the livelihood was based on foraging throughout the period. [ABSTRACT FROM AUTHOR]

A sediment core from a lagoon in southeastern Cuba was the focus of a multi-proxy paleoenvironmental study to investigate lagoon response to sea-level change and climate change and also to infer changes in the frequency of past hurricane strikes. The proxy data examined included benthic foraminifera, fossil pollen, particle size analysis, and macrocharcoal influx values. The core was dated using 137Cs and accelerator mass spectrometry (AMS) radiocarbon methods. The results show that lagoon formation began approximately 4000 years ago and that the lagoon environment evolved through four phases: (1) from ~4000 to 2800 cal. yr BP, the lagoon was a shallow polyhaline to euryhaline system with limited mangrove coverage; (2) from ~2800 to 2000 cal. yr BP, there was a decrease in salinity which facilitated the expansion of red mangrove; (3) from ~2000 to 1000 cal. yr BP, sea-level rise resulted in an increase in water depth and possibly salinity; and (4) from ~1000 cal. yr BP to the present, water level continued to rise and the mangrove environment diversified. The shift to lower salinity conditions from ~2800 to 2000 cal. yr BP may have been climate driven as similar changes are seen at lagoons elsewhere in Cuba. The particle size data show several periods where sand-sized particles are more abundant; these periods are similar to data from Puerto Rico that document times of relatively frequent hurricanes. This paper shows that coastal lagoons are useful archives of paleoclimatic and paleoenvironmental information in the Caribbean region and that they should be the focus of additional research efforts. [ABSTRACT FROM AUTHOR]

This paper is based on a multidisciplinary study using both paleoenvironmental methods (biological, sedimentological, magnetic and geochemical) and archaeological data in order to characterize landscape and hydrological network changes as well as human impact on a littoral catchment in the Western Mediterranean area. Sedimentary records obtained around a coastal alluvial plain (Cassis, Southeastern France) reveal local environmental changes and human activities since the Neolithic (ca. 6000 cal. BP). Anthropogenic impact is already noticeable in the earliest record, and we follow its evolution through time. According to biological markers, the Holocene landscape of the Calanques is dominated by a mosaic of open herbaceous formations partly generated by human activity. The prevalence of Cernuella virgata in malacofauna successions and of coprophilous fungal spores in the pollen record testifies to the spread of agro-pastoral activities. Two increases of anthropogenic impact are highlighted during the Roman (ca. 2000 cal. BP) and Modern (from ca. 1450 to today) periods. Lead isotope analyses indicate an anthropogenic release of lead, possibly originating from the Greek Cyclades (ca. 2000 cal. BP). Hydrographic and agricultural work is also enhanced during the Roman period. Magnetic parameters and lead isotopes indicate that the Modern anthropogenic impact may be associated with high temperature activities (e.g. lime kiln, fossil fuel). [ABSTRACT FROM AUTHOR]

This paper presents an integrated approach to assess Holocene environmental changes in the Sperchios delta, Sperchios rift, central Greece. A multidisciplinary study was carried out applying established analytical methods as well as exploring new techniques to detect past environmental conditions in a fluvio-deltaic depositional system. A series of six deep boreholes, up to 50 m long, and four shallow cores, up to 6 m long, from across the delta plain, were studied in detail. Sedimentary facies were defined by changes in grain size and macro- and microfaunal composition. Variability in mineral magnetic composition documented by changes in bulk magnetic susceptibility (χ and χ77K/χ293K) and remanence parameters (S−300 and σARM/σSIRM ratios), as well as down-core elemental variations obtained by scanning micro-x-ray fluorescence (µ-XRF), provide constraints on the depositional changes related to the evolution of the Sperchios delta. Correlations between elemental data derived by µ-XRF analyses and grain size were also analyzed and used to further constrain the facies interpretation. Overall, these Holocene sediments reveal a transgressive–regressive succession overlying pre-transgressive terrestrial deposits of Late Pleistocene–Early Holocene age. Furthermore, 13 new 14C radiocarbon dates constrain the transgression rate to be ~3.5 m/yr for the Early Holocene and the regression rate to be ~1 m/yr for the Late Holocene. The Sperchios delta plain developed when the rate of sea-level rise decreased ~6000 cal. yr BP as it has been proposed for the broader area of Aegean Sea. This study demonstrates that the combination of techniques used here provides a powerful way to map out paleoenvironmental changes and thus the 3D stratigraphic architecture of Holocene sedimentary successions. [ABSTRACT FROM AUTHOR]

In the eastern United States, existing paleo-reconstructions in fluvial environments consist primarily of site-specific investigations of climate and human impacts on riverine processes. This paper presents the first meta-analysis of fluvial reconstructions focused on regional watersheds of the eastern United States, including the Lower Mississippi, Tennessee, South Atlantic–Gulf Coast, Ohio, Mid-Atlantic, and New England regional watersheds. Chronologies of fluvial activity (i.e. alluvial deposition) and stability (i.e. landscape stability) were developed by synthesizing data from existing, published, and site-specific fluvial reconstruction studies conducted across the eastern United States. Overall, regional watersheds show variable patterns of synchronicity across watersheds and did not demonstrate cyclic behavior through the Holocene. During the last millennium, only the Lower Mississippi and Ohio regional watersheds exhibit high rates of fluvial activity active during the 'Medieval Climate Anomaly' (650–1050 yr BP), while nearly all other regional watersheds in the eastern United States were active during the 'Little Ice Age' (100–500 yr BP). These findings imply that fluvial activity may be more spatially restricted during warmer/drier climatic conditions than during cooler/wetter periods. We find an increase in fluvial activity during the era of Euro-American colonization (400 yr BP to present) in the southeastern United States but not the northeastern United States, implying a heterogeneous response of fluvial systems to human activities in the eastern United States related to climatic, cultural, and/or physiographic variability. These new insights gained from fluvial chronologies in the eastern United States demonstrate the utility of regionally synthesized paleo-records to understand large-scale climate variation effect on rivers. [ABSTRACT FROM AUTHOR]

This paper reports the results of new malacological analyses from a thick tufa sequence at Direndall (Luxembourg). The study is temporally contextualised with radiocarbon dates and an age–depth model. The malacological study focuses on species associations to reconstruct palaeoenvironmental developments. The gradual appearance of several shade-demanding species reflects the expansion of forest environments during the early Holocene. After c. 7.5 cal. kyr BP, three phases of maximal expansion of shade-demanding species are interspersed with two phases of decline of these taxa dated between c. 7.1 and 6.5 cal. kyr BP and between c. 3.5 and 2.4 cal. kyr BP. Malacological data are discussed with previously published calcite stable isotope data from the same sequence. Strong correlations between malacological data and δ13C profile are highlighted over the whole sequence. Combined influences of local environmental conditions and regional climatic trends are emphasised. The sequence provides a palaeoenvironmental succession free of any anthropic influence. [ABSTRACT FROM AUTHOR]

The hemispheric-scale climatic fluctuations during the Holocene have probably influenced the large Siberian rivers. However, detailed studies of the West Siberian Plain postglacial environmental change are scarce and the records of millennial-scale palaeohydrology are nearly absent. This paper presents the Holocene palaeoecological reconstruction based on the sedimentary record of Lake Svetlenkoye, located near the confluence of major Siberian rivers Ob and Irtysh. Postglacial history of flooding, dynamics of regional and local vegetation, sedimentation regime, geochemical changes and lake water pH were reconstructed based on multi-proxy studies. We used palaeobotanical (plant macrofossils, pollen, diatoms), geochemical (organic matter, total organic carbon and nitrogen content, carbon/nitrogen ratio) and chronological (14C dates, spheroidal fly-ash particle counts) methods. The studied sediment section started to accumulate ~11,400 cal. yr BP. The initial shallow water body was flooded by Ob River waters ~8100–8000 cal. yr BP as confirmed by a remarkable increase in the sedimentation rate and the accumulation rate of the aquatic vegetation proxies. The period of flooding coincides with the high humidity periods reconstructed from regional palaeobotanical records. About 6800–6700 cal. yr BP, the study site became isolated from the Ob River floodplain and remained a small lake until present. The diatom-based lake water pH estimates suggest fluctuations in the pH values during the Holocene, the recent decrease since 1960s being the most notable. The vegetation record revealed constant postglacial presence of tree taxa – Betula, Pinus and Picea – although in different pollen ratios and accumulation rates through time. The paludification of the surroundings occurred since ca. 8500 cal. yr BP. [ABSTRACT FROM AUTHOR]

In this paper, we provide a comprehensive overview of the state-of-knowledge of dust flux and variability in time and space in different sectors of East Antarctica during the Holocene. By integrating the literature data with new evidences, we discuss the dust flux and grain-size variability during the current interglacial and its provenance in the innermost part of the East Antarctic plateau as well as in peripheral regions located close to the Transantarctic Mountains. The local importance of aeolian mineral dust aerosol deflated from low-elevation areas of peripheral East Antarctica is also discussed in the light of new data from several coastal, low-elevation sites. [ABSTRACT FROM AUTHOR]

The transformation of natural landscapes in Middle Europe began in the Neolithic as a result of the introduction of food-producing economies. This paper examines the relation between land-cover and demographic change in a regionally restricted case study. The study area is the Western Lake Constance area which has very detailed palynological as well as archaeological records. We compare land-cover change derived from nine pollen records using a pseudo-biomisation approach with 14C date probability density functions from archaeological sites which serve as a demographic proxy. We chose the Lake Constance area as a regional example where the pollen signal integrates a larger spatial pattern. The land-cover reconstructions for this region show first notable impacts at the Middle to Young Neolithic transition. The beginning of the Bronze Age is characterised by increases of arable land and pasture/meadow, whereas the deciduous woodland decreases dramatically. Changes in the land-cover classes show a correlation with the 14C density curve: the correlation is best with secondary woodland in the Young Neolithic which reflects the lake shore settlement dynamics. In the Early Bronze Age, the radiocarbon density correlates with open land-cover classes, such as pasture, meadow and arable land, reflecting a change in the land-use strategy. The close overall correspondence between the two archives implies that population dynamics and land-cover change were intrinsically linked. We therefore see human impact as a key driver for vegetation change in the Neolithic. Climate might have an influence on vegetation development, but the changes caused by human land use are clearly detectable from Neolithic times, at least in these densely settled, mid-altitude landscapes. [ABSTRACT FROM AUTHOR]

Proxies that use changes in the composition of ecological communities to reconstruct temporal changes in an environmental covariate are commonly used in paleoclimatology and paleolimnology. Existing methods, such as weighted averaging and modern analog technique, relate compositional data to the covariate in very simple ways, and different methods are seldom compared systematically. We present a new Bayesian model that better represents the underlying data and the complexity in the relationships between species' abundances and a paleoenvironmental covariate. Using testate amoeba–based reconstructions of water-table depth as a test case, we systematically compare new and existing models in a cross-validation experiment on a large training dataset from North America. We then apply the different models to a new 7500-year record of testate amoeba assemblages from Caribou Bog in Maine and compare the resulting water-table depth reconstructions. We find that Bayesian models represent an improvement over existing methods in three key ways: more complete use of the underlying compositional data, full and meaningful treatment of uncertainty, and clear paths toward methodological improvements. Furthermore, we highlight how developing and systematically comparing methods lead to an improved understanding of the proxy system. This paper focuses on testate amoebae and water-table depth, but the framework and ideas are widely applicable to other proxies based on compositional data. [ABSTRACT FROM AUTHOR]

This paper describes long-term changes in human population and vegetation cover in southern France, using summed radiocarbon probability distributions and site count data as population proxies and information from fossil pollen cores as a proxy for past land cover. Southern France is particularly well-suited to this type of study as a result of previous programmes of intensive survey work and excavation in advance of large-scale construction. These make it possible to calibrate the larger scale occupation patterns in the light of the visibility issues created by the burial of archaeological sites beneath alluvial sediments. For purposes of analysis, the region was divided into three biogeographical zones (BGZ), going from the Mediterranean coast to the middle Rhône valley (MRV). All the different population proxies in a given zone show broadly similar patterns of fluctuation, though with varying levels of resolution. The long-term patterns in the different zones all show significant differences from the overall regional pattern, but this is especially the case for the non-Mediterranean middle Rhône area. Cluster analysis of pollen samples has been carried out to identify the main regional land cover types through the Holocene, which are increasingly dominated by open types over time. A variety of other pollen indicators show evidence of increasing human impact through time. Measures of human impact correlate strongly with the population proxies. A series of thresholds are identified in the population–human impact trajectory that are related to other changes in the cultural sequence. The lack of independent climate data for the region means that its impact cannot currently be assessed with confidence. However, for the later periods, it is clear that the incorporation of southern France into larger regional systems played a major role in accounting for changes in land cover and settlement. [ABSTRACT FROM AUTHOR]

This synthesis paper offers a comparative perspective on how seven different Mediterranean regions, from Iberia and Morocco to the Levant, have been transformed by human and natural agencies during the past 10 millennia. It draws on a range of data sources: notably (1) archaeological site surveys (n = 32,000) and 14C dates (n = 12,000) as proxies for long-term population change, (2) pollen records as a proxy for past vegetation and land cover (n = 253) and (3) proxies, such as stable isotopes, from lake, cave and marine records as indicators of hydro-climate (n = 47). Where possible, these data sets have been made spatially and temporally congruent in order to examine relationships between them statistically and graphically. Data have been aggregated or averaged for each region/sub-region and put into 200-year time windows. Archaeo-demographic data show a clear increase at the start of Neolithic farming, followed by a series of regionally asynchronous fluctuations in population, prior to a pan-Mediterranean Roman settlement maximum. Pollen data indicate a late-Holocene decline in %Arboreal Pollen in those regions that were initially well wooded, but not in drier regions of the southern/eastern Mediterranean. Overall, the clearest palynological proxy for human land cover change is provided by the OJCV (tree crop) index. The cultivation of these trees in the eastern Mediterranean after 6500 cal. yr BP may have been an adaptive response to mid-Holocene climatic desiccation. These anthropogenic pollen indicators correlate more closely with trends in population than with regional hydro-climatic z scores, implying that they reflect primarily human activities. During the mid Holocene, most Mediterranean landscapes were transformed by a combination of climate and rural land use, but after ~3500 cal. yr BP, human actions became increasingly dominant in determining land cover. During the past 1500 years, the dominant landscape trajectory in the eastern Mediterranean was markedly different to that in the central/western Mediterranean. [ABSTRACT FROM AUTHOR]

In historical urban centres, the superimposition of excavation and deposition activities over time has resulted in an irregular spatial distribution of anthropogenic deposits, which may reach considerable thicknesses. The detection of those thicknesses requires extensive investigations. Broad borehole and geophysical campaigns cost time and money, consequently at the urban-planning level, it is usual to shift to an estimation of thicknesses, which may be performed through map-algebra operations, that is, by subtracting from the modelled ground surface the elevation of the anthropogenic-deposit basal surface. The latter is implemented through the interpolation of point elevation data, which are generally provided by borehole logs. Despite the development of advanced spatial interpolation methodologies, previous modelling results in the literature show that if the process is affected by insufficient input data, it produces imprecise interpolation outputs. This paper reports an interdisciplinary methodology aiming at enhancing elevation datasets, in order to obtain more accurate digital elevation models. The increase in number and spatial distribution of input points is achieved through past-landscape analyses mainly based on elevation data given by borehole logs, available archaeological reports and historical topographic maps, these being generally available for historical urban centres. The methodology was tested in an urban sector of Rome, where significant activities have been performed for millennia particularly during the Roman Age. A reliable model of the basal surface of the anthrostrata led to a better estimation of the spatial distribution of such deposits and, in addition, revealed the original topographic surface, as modified by human activities. [ABSTRACT FROM AUTHOR]

This article is a brief introduction to the Special Issue on Holocene Dust Dynamics, which brings together recent research on a key aspect of the Earth's changing climate through its effects on radiative balance, cloud cover and biogeochemical cycles. The aim of the Special Issue is to contribute to a better understanding of the role of dust aerosols by analysing the evolution and climatic impact of atmospheric dust over long and short timescales within the Holocene. Here, we introduce the rationale behind the Special Issue and the eight research papers, which include long-term records of dust deposition from different types of natural archive (e.g. peatlands, ice, loess and lake sediments) as well as present-day multi-annual dust trap records and process studies from various climatic regimes that have global implications. [ABSTRACT FROM AUTHOR]

Paleotempestology, the study of past tropical cyclone activity, has grown considerably over the past two decades, and there is now a relatively dense network of sites across the Western North Atlantic Basin providing records of past tropical cyclone variability. This paper presents a new database of paleotempestological records generated from 61 studies published between 1993 and 2018 for this region. A total of 266 data entries, consisting of the calibrated ages of individual tropical cyclone events and the boundaries of ‘active’ tropical cyclone periods from the present to 8000 cal. yr BP, along with the site names, geographic coordinates, proxy indicator(s) used, materials upon which dating was undertaken, and information about the depositional basin type (e.g. lagoon, mangrove), are included in the database for each site. The database is housed at the National Oceanographic and Atmospheric Association (NOAA) (https://www.ncdc.noaa.gov/paleo/study/21391) and is available for free download. This publicly available database will permit a greater number of researchers to work on questions related to past tropical cyclone dynamics and more easily allow studies of long-term spatial-temporal tropical cyclone relationships to be undertaken. [ABSTRACT FROM AUTHOR]

This paper reviews the reconstruction of European Atlantic storm events with the contribution of a new stormy reconstruction in its central part. Three marsh environments on the island of Yeu were chosen to identify disturbing storm events from the Mid- to Late Holocene with vibracore sampling, radiocarbon dating and sedimentary analysis. Nine probable intervals of high energy deposition in these low-transport-activity environments are estimated: 600–500, near 1590, 2100–1950, 2850–2350, 3500–3270, 5400–5370, 6650–6510, near 7000 and between 7670 and 7470 calibrated years before present (cal y BP). By comparison with sedimentological paleostorm studies, we confirm six European Atlantic storm events estimated at near 600–300, 1700–1100, 2900–2500, 3500–3300, 5500–5100 and 7700–7100 cal y BP, corresponding to worldwide Holocene cooling climatic periods. A comparison with other storminess reviews of worldwide main stormy coasts shows that Holocene storms can increase during global cooling periods in the northern hemisphere. [ABSTRACT FROM AUTHOR]

The most important stratified screes of the Iberian Range are found in Sierra de Albarracín. These slope deposits have been traditionally considered, without absolute datings, as having been formed during various Pleistocene cold phases. The aim of this paper is to establish the sedimentological, morphological, chronological, and paleoenvironmental characteristics of these deposits through the study of four profiles recorded in the Calomarde canyon (El Rollo, El Molino, and Royuela) and Toril. The most representative profile is that of El Rollo as it is formed by basal tufa and stratified scree layers separated by paleosoils. Radiocarbon datings obtained from paleosoil samples show that the sequence ranges between the early and middle Holocene. The profiles from El Molino and Royuela, as well as the upper levels of Toril, complete the sequence showing deposits from upper Holocene (Bronze Age and ‘Little Ice Age’). These data show the oscillations during the Holocene between colder phases, represented by the stratified screes, and warmer–wetter phases with soil development and local tufa deposits. This geomorphological and pedological response to the Holocene climatic variability shows its clearest records in the canyons. However, there are almost no Pleistocene accumulations – with the exception of that of Toril (minimum age of <43.5 ka BP). The possibility of relating this succession of Holocene environmental changes to known regional and global climatic stages converts these accumulations into the most important Holocene paleoenvironmental record from the Iberian Ranges and the most complete sequence of Holocene stratified screes from the Mediterranean area. [ABSTRACT FROM AUTHOR]

In this paper, we presented a reply to the comments on modern pollen rain and interpretations about the Last Glacial Maximum (LGM) by D’Apolito et al. Carajás may be considered as a micro-hotspot of plant endemism, mainly related to edaphic conditions and presence of different micro-habitats for canga vegetation into ironstone domains. These plants developed several survival strategies, including morphological and physiological adaptations, which is difficult for comparisons with any other distinct biomes or ecosystems. Furthermore, inaccurate interpretation of pollen taxa and habitat types by the previous palynological studies in Carajás, which are keys points presented in Guimarães et al., were not questioned by D’Apolito et al. Therefore, incomplete pollen database, uncertainties about pollen descriptions and plant–pollen habitat, poor knowledge about pollen production and dispersion in edaphically conditioned areas, as well as missing of multiproxy evidences about geology, geomorphology, faciology, and geochemistry can make LGM interpretations a very challenging task. This can produce more noises than reliable signals of paleoclimate changes. [ABSTRACT FROM AUTHOR]

A comprehensive and integrative view of East Asian monsoon evolution during the Holocene is still under debate, and additional high-resolution proxy records from climatically sensitive locations are requisite to solve this complex issue. In this paper, we present three well-dated mud/peat cores from a paleo-pingo depression in the Sanjiang Plain, a climatically sensitive region to monsoon variation, to reveal the paleoenvironmental history of the wetland and discuss the regional impacts from monsoon evolution. A paleolake developed in the study area before 5.5 ka BP, and a peatland initiated thereafter consequent upon the gradual shrinking of the paleolake. This transition lasted until 4.5 ka BP, when the paleolake changed entirely to a wetland. Considering the prevalent monsoon climate in the Sanjiang Plain, we suggest that the lake-to-wetland transition from 5.5 to 4.5 ka BP indicates a rapid decline of the East Asian summer monsoon in addition to autogenic basin infilling processes. Such a remarkable monsoon weakening event has been documented across northern China, and we associate this with ocean–atmosphere interactions throughout low-latitude regions. [ABSTRACT FROM AUTHOR]

This paper concerns the relative sea-level changes associated with the Atlantic Patagonian coast derived from sea-level index points whose elevation was determined by a differential global position system (DGPS). Bioencrustations from outcrops located near Camarones, Chubut, Argentina, consist of autochthonous deposits characterized by Austromegabalanus psittacus (Molina, 1782), encrusting acervulinid foraminifera, coralline red algae and bryozoans. The association of the different organisms is interpreted as being associated with an intertidal environment, and they have been used as index points to establish the relative sea-level position. The main conclusion is that the relative sea-level between c. 7000 and 5300 cal. yr BP was in the range of c. 2-4 m a.s.l., with a mean value of c. 3.5 m a.s.l. Our data seem to support the existence of different rates of relative sea-level fall in different sectors of Atlantic Patagonia during the Holocene and highlight the importance of a more precise and accurate relative sea-level estimation by producing new data and revisiting the indicative meaning of most of the indicators so far used in the area. [ABSTRACT FROM AUTHOR]

In this paper, we reconstruct the Holocene paleoenvironmental evolution of the Guadiana Estuary, southwestern Iberian Peninsula. Two previously studied boreholes (CM3 and CM5) were revisited and analyzed in the light of a foraminifera modern analog approach. Cluster analyses define four assemblages with different biocenotic, taphonomic, elevation and distance-to-sea settings, which serve as a baseline for paleoassemblages interpretation. Faunal changes along the sedimentary sequences, together with previous sedimentological and chronological data, redefine the different phases of environmental evolution in the Guadiana Estuary since ca. 13 kyr cal. BP, with special emphasis on the Holocene marine highstand. Estuarine flooding began synchronously in both locations (ca. 9 kyr cal. BP) but manifested differently in each sedimentary sequence. The most seaward borehole records a more evident and longer highstand (ca. 8.8-3.8 kyr cal. BP), characterized by the occurrence of subtidal environments and by the presence of open marine species (Pararotalia cf. spinigera, planktic forms and a significant number of exotic/allochthonous tests), indicating warmer and more marine conditions than today. In the most landward borehole, the highstand is shorter (ca. 8-7.6 kyr cal. BP) and less intense, characterized by the presence of a diverse, mainly autochthonous, open estuary assemblage, dominated by Ammonia aberdoveyensis and Haynesina germanica. At 4.4 kyr cal. BP, during a long deceleration phase of regional sea-level rise, a short but well-defined pulse of marine influence is recorded in CM5, when open estuarine assemblages reappear and replace marsh agglutinated assemblages, suggesting a new submergence phase. This short event is not identified in the previous works carried out in the same area, thus further data are needed to understand whether it is consequent from a global, warming period or whether it resulted only from local and ephemeral forcing effects. [ABSTRACT FROM AUTHOR]

Recent research in northern Iceland has highlighted a significant period of rock slope instability during the early Holocene due to the combined effects of postglacial rebound, relative sea-level fall, and glacially oversteepened mountain slopes. Using the Vatn landslide (Skagafjörður, central northern Iceland) as an example, this paper focuses on this period and describes the sequence of events that led to landsliding. Geomorphic mapping, stratigraphical evidence, and both radiocarbon and tephra dating were applied. Collectively, the data acquired indicate that the landslide occurred between 11,400 and 10,790 cal. yr BP. However, while rock slope failure represents a significant disintegration of mountain slopes, this study suggests that large postglacial landslides might also play a role in arresting sediment transport from other hillslope processes rather than contributing large volumes of sediment. [ABSTRACT FROM AUTHOR]

Lacustrine sediments retain Cladocera (Crustacea) subfossils (carapaces, ephippia, head shields, and postabdomens) from the Holocene, which allows reconstructing past aquatic communities and environmental changes. In late Holocene (Subatlantic) fossils, among many Cladocera species, we noticed the appearance of several Bosmina (Eubosmina) species in lakes surrounding the Baltic Sea. These species were never recorded in the early Holocene. The appearance of these species is a record of very recent speciation, which took place during the last millennium in lakes surrounding the Baltic Sea. Contemporary data show co-occurrence of several Bosmina (Eubosmina) species (longispina, kessleri, reflexa, ruehei, coregoni, gibbera, thersites). These species are not a product of invasion or introgressive hybridization, but in fact, they are probably a product of speciation. Here, we present the palaeolimnological evidence of this speciation from the only one species, Bosmina (Eubosmina) longispina, found in lacustrine sediments from the last interglacial and glacial periods. [ABSTRACT FROM PUBLISHER]

Dinoflagellate cyst (dinocyst) records from the southern Nordic Seas were compiled in order to evaluate the evolution of upper ocean conditions, on a millennial timescale and supported by a highly resolved record from the Vøring Plateau. After the transitional phase from the last deglaciation, three main phases define the Holocene. The early Holocene (>7.5 ka BP) features important numbers of cool-temperate species dominated by Nematosphaeropsis labyrinthus and Impagidinium pallidum in the west. The assemblage composition changes drastically at the transition from the early to the mid-Holocene, from when on Operculodinium centrocarpum dominates. The changeover is dated between ~6.1 and 7.5 ka BP, perhaps earlier closer to the Iceland–Scotland Ridge, and appears to be linked to the onset of a modern type of surface circulation. ‘Warmest’ assemblages occur at the Vøring Plateau shortly after the transition, when Atlantic waters also appear to have spread farthest westward. The recurrence of colder elements can be linked to cooling from ~2.4 ka BP at the Vøring Plateau and presumably earlier in the west but is difficult to date there because of the low sedimentation rates. This is a general issue in many areas of the Nordic Seas and appears to have an important effect on cyst concentrations and assemblage composition, with the possible loss of oxygenation-sensitive cysts in the older parts of the cores. Comparing dinocyst-based quantitative reconstructions with those retrieved from other plankton reveals a significantly different trend between proxies, linked to a differing autecological response to seasonal changes at their respective depth habitats. [ABSTRACT FROM AUTHOR]

Holocene fluctuations of a small outlet glacier from the ice cap Høgtuvbreen at 65° N in coastal northern Norway are reconstructed based on distal glacier-fed lake sediments, complemented by a moraine sequence dated by lichenometry. Glaciers respond to changes in accumulation-season precipitation, ablation-season temperature and redistribution of snow by wind. Hence, reconstructions of glacier fluctuations based on distal glacier-fed lakes may give detailed information about past climate at a potentially high temporal resolution. Yet, the importance of any of these climate components is often difficult to solve. Here, we apply the ‘Liestøl-relationship’, which expresses the relationship between ablation-season temperature and annual accumulation of snow at the equilibrium line altitude (ELA), to the reconstructed local temperature–precipitation–wind ELA (TPW-ELA) to infer the relative importance of winter-balance and ablation-season temperature as causes of reconstructed glacier variation. The reconstructions show a large glacier readvance corresponding with the 8.2-ka cold event and a sequence of eight distinct glacier advances and retreats during the Neoglacial time period bracket between 4300 ± 40 cal. yr BP and AD 1900. The glacier reached its Holocene maximum position in AD 1773 ± 29, subsequently followed by an ongoing unprecedented retreat, interrupted only by some minor halts and readvances. Based on a detailed comparison of our results with similar studies of both continental and maritime glaciers, as well as independent temperature proxy records across Scandinavia, we argue that significant and consistent deviations in ELA fluctuations between continental and maritime glaciers in the region are caused by a north–south migration of the arctic polar front. Additionally, we suggest that deviations in ELA fluctuations between Scandinavian maritime and continental glaciers around 7150, 6560, 6000, 5150, 3200 and 2200 cal. yr BP reflect the different response of continental and maritime glaciers to drops in total solar irradiance (TSI). [ABSTRACT FROM AUTHOR]

This study investigates the possibility of Holocene glaciation on Mount Olympus (Greece) with a respective local temperature–precipitation equilibrium line altitude (TP-ELA) at c. 2200 m a.s.l., based on geomorphologic and paleoclimatic evidence. At present, the local TP-ELA is situated above the mountain’s summit (c. 2918 m a.s.l.), but permanent snowfields and ice bodies survive within Megala Kazania cirque between c. 2400 and c. 2300 m a.s.l., because of the cirque’s maritime setting that results from its close proximity (c. 18 km) to the Aegean Sea and of the local topographical controls. The snow and ice bodies occupied a considerably larger area and attained a stabilization phase between AD 1960 and 1980, also manifested from aerial photographs, a period characterized by increased winter precipitation (Pw) with subsequent TP-ELA depression to c. 2410 m a.s.l. Mid- to late-20th-century Pw and TP-ELA variations exhibit negative correlations with the winter North Atlantic Oscillation index (NAOw) at annual and multidecadal (30 years) timescales. Late Holocene (AD 1680–1860) reconstructed summer mean temperatures were lower by Ts < 1.1°C in relation to the reference period between AD 1960 and 1980 and were also superimposed to negative NAOw phases, thus bracketing this time interval as a favorable one to glacial formation and/or advance. Millennial-scale annual precipitation reconstructions at the hypothesized TP-ELA (c. 2200 m a.s.l.) point the period between 8 and 4 kyr BP as another glacier-friendly candidate. The mid-Holocene rather simplistic sequence of potential glacial advance phase was disturbed by short-lived cold climatic deteriorations, well-documented over the northern Aegean region that may partly explain the multicrested shape of the highest (c. 2200 m a.s.l.) morainic complex of Megala Kazania cirque. [ABSTRACT FROM AUTHOR]

The arrival in Australia of Europeans and the species they brought with them initiated a sharp decline in native mammalian biodiversity. Consequently, one-third of the original or pre-European terrestrial mammal fauna is now extinct or threatened with extinction. Although the distributional ranges of many Australian mammals have contracted markedly, modern distributions are frequently used as baselines for conservation management and understanding ecological requirements. However, these often poorly reflect pre-European distributions, particularly in areas where biodiversity declines were rapid and occurred soon after European arrival. Here we analyse two late Holocene mammalian assemblages from Fleurieu Peninsula, South Australia, and reconstruct the pre-European terrestrial non-volant mammal fauna. The region was previously estimated to have lost perhaps 30% of its original terrestrial non-volant mammal fauna, but our results indicate a loss of almost 50%. We provide the first local records of the murids Mastacomys fuscus, Pseudomys australis, P. gouldii, P. novaehollandiae and P. shortridgei, and confirm the past occurrence of the now-extinct Conilurus albipes. Our study contributes new knowledge of species biogeography and ecology and will help refine restoration targets. [ABSTRACT FROM AUTHOR]

The present-day Lesina area (Adriatic coast of southern Italy) preserves in the subsurface the stratigraphic signature of a recent sedimentary process regime change, which was responsible for the conversion of a former alluvial plain into a back-barrier tidal flat and, finally, into the modern barrier island. Facies-based analyses of the first 55 m of the upper Pleistocene–Holocene stratigraphic record, integrated with biostratigraphic sampling, radiocarbon data, and aerial observations of some diagnostic relict morphologies, allowed us to reconstruct the history of the last 20,000 years of this area. The succession investigated is adjacent to a salt dome, which uplifted in recent times, forming the easternmost boundary of the present-day Lesina lagoon. Three main stratigraphic intervals were detected in the subsurface: the lowermost unit is made up of conglomerates, sandstones, and mudstones of terrestrial origin, belonging to a complex system of alluvial plain filling a pre-existing Last Glacial Maximum (LGM) topography. The second interval consists of sands and muds, with subordinate conglomerates of brackish and marine origin, and lies on the previous one through a wide ravinement. Its composing lithofacies exhibit a strong tidal signature preserved in tidal rhythmites belonging to a net of tidal channels, associated with marshes, mud flat, and lagoonal deposits. These sediments record the emplacement of a back-barrier tidal flat, which developed under the strong influence of a tidal influx enhanced by the late post-LGM transgression. The third uppermost interval resulted from the deposition of coastal-marine sands and gravels accumulated during the ensuing modern normal regression, under the dominance of a wave-dominated coastal dynamics, which was responsible for the progradation of the present-day beach barrier and the closure of the Lesina lagoon. The paleogeography of the back-barrier tidal flat preceding the onset of the modern barrier island is thus reconstructed based on the results of our facies analysis, biostratigraphy, and AMS dating. Many of the elements composing this mid-Holocene tide-influenced system were also interpreted from the aerial-photograph observation of several relict morphologies, which are still preserved in many parts of the modern Lesina barrier island. We propose some new interpretation on the origin some of these elements, which possibly developed under sedimentary process regimes different from the modern ones, including some flood-tidal deltas, previously interpreted as tsunami-derived washover fans. [ABSTRACT FROM AUTHOR]

The moisture history in arid central Asia (ACA) differs from that in the Asian monsoon region during the Holocene. Much less is known about causes of Holocene moisture changes in ACA than Asian monsoon precipitation changes, hampering our understanding of their spatiotemporal differences. In this study, orbital-scale evolution of winter rainfall in northwestern China (a part of the core zone in ACA) during the Holocene and possible driving mechanisms are investigated using results from a long-term transient simulation performed by an atmosphere–ocean–sea-ice coupled general circulation model, the Kiel Climate Model, forced by orbital variations. Our results reveal a persistent wetting trend in northwestern China in winter throughout the Holocene, which is in response to winter insolation at mid-northern latitudes. Winter insolation can influence the rainfall via three ways. First, increasing latitudinal gradient of the incoming solar insolation at mid-latitudes strengthens the westerly intensity. Second, the evaporation is enhanced because of insolation-induced winter temperature rising, resulting in an increase in the air humidity. Intensified westerly winds and the increased water vapour together are conductive to enhance moisture transport towards northwestern China and thus increase winter precipitation in this area. Third, the increasing trend of winter insolation weakens the East Asian winter monsoon, which is favourable for the formation of rainfall via crippling the Siberian High that is beneficial for atmospheric lifting motion. [ABSTRACT FROM AUTHOR]

The Michoacán–Guanajuato Volcanic Field is the largest subduction-related monogenetic volcanic field in the world and includes more than 1000 scoria cones and a few hundred medium-sized volcanoes. Although medium-sized volcanoes (domes and shields) are less abundant, hazards associated with the renewal of this type of activity should not be neglected. Here, we focus on El Metate volcano, the morphologically youngest shield of the field. This volcano has a minimum volume of ~9.2 km3 DRE, and its viscous lava flows were emplaced during a single eruption over a period of ~30 years covering an area of 103 km2. El Metate is thus best labeled as a monogenetic andesite shield. This eruption had a significant impact on the environment (modification of the hydrological network, forest fires, etc.), and hence, nearby human populations probably had to migrate. New C14 dates for the eruption yield a young age (~AD 1250), which briefly precedes the initial rise of the Tarascan Empire (AD 1350–1521) in this region. By volume, this is certainly the largest eruption during the Holocene in the Trans-Mexican Volcanic Belt, and it is the largest andesitic effusive eruption known worldwide for this period. Such a large volume erupted in a relatively short time bears important implications for evaluating future hazards in the Michoacán–Guanajuato Volcanic Field. [ABSTRACT FROM AUTHOR]

Lake La Thuile, in the Northern French Prealps (874 m a.s.l.), provides an 18-m long sedimentary sequence spanning the entire Lateglacial/Holocene period. The high-resolution multi-proxy (sedimentological, palynological, and geochemical) analysis of the uppermost 6.2 m reveals the Holocene dynamics of erosion in the catchment in response to landscape modifications. The mountain belt is at relevant altitude to study past human activities, and the watershed is sufficiently disconnected from large valleys to capture a local sedimentary signal. From 12,000 to 10,000 cal. BP (10–8 kyr cal. BC), the onset of hardwood species triggered a drop in erosion following the Lateglacial/Holocene transition. From 10,000 to 4500 cal. BP (8–2.5 kyr cal. BC), the forest became denser and favored slope stabilization, while erosion processes were very weak. A first erosive phase was initiated at ca. 4500 cal. BP without evidence of human presence in the catchment. Then, the forest declined at approximately 3000 cal. BP, suggesting the first human influence on the landscape. Two other erosive phases are related to anthropic activities: approximately 2500 cal. BP (550 cal. BC) during the Roman period and after 1600 cal. BP (350 cal. AD) with a substantial accentuation in the Middle Ages. In contrast, the lower erosion produced during the ‘Little Ice Age’, when climate deteriorations are generally considered to result in an increased erosion signal in this region, suggests that anthropic activities dominated the erosive processes and completely masked the natural effects of climate on erosion in the late Holocene. [ABSTRACT FROM AUTHOR]

Despite their huge extent, the peatlands of Russia are an under-exploited source of data on palaeoenvironmental change. We investigated the Holocene history of Staroselsky Moch, an ombrotrophic peatland in the Tver Region of European Russia by analysis of testate amoebae, peat physical properties, plant macrofossils and pollen. The peatland developed through a classic hydroseral succession in the early Holocene with a sharp decline in mineral input to 6200 cal. BC followed by an abrupt transition from fen to bog vegetation around 5500 cal. BC. Through the Holocene, the peatland has accumulated carbon at a mean apparent rate of 21.5 g C m−2 yr−1 suggesting that carbon accumulation rates in peatlands of European Russia lie close to the global average, and contrasting with a short sequence of eddy-covariance data which implies a net loss of carbon. The testate amoeba record shows considerable variability which may be driven by climate, but changes are not well replicated in the macrofossil or pollen data. We tentatively infer (1) a phase of early Holocene warming commencing around 7200 cal. BC, (2) dry peatland surface conditions c. 3700–3900 cal. BC, (3) a shift to wetter conditions from c. 3900 cal. BC, and (4) drier conditions from c. 400 cal. BC onwards. More robust and precise hydroclimatic reconstructions for this region will require the development of a regional transfer function and the replication of results between cores and sites. [ABSTRACT FROM AUTHOR]