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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]

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]

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]

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]

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 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]

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]

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]

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]

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]

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]

Peatlands represent the largest and most concentrated carbon pool in the terrestrial biosphere, and their dynamics during the Holocene have had significant impacts on the global carbon cycle. In this Introduction paper, we provide an overview of the contributions presented in this Special Issue on Holocene peatland carbon dynamics. We also provide a brief history and current status of peat-core-based research on peatland carbon dynamics. Finally, we identify and discuss some challenges and opportunities that would guide peatland carbon research in the near future. These challenges and opportunities include the need to fill data gaps and increase geographic representations of peat carbon accumulation records, a better understanding of peatland lateral expansion process and improved estimate of peatland area change over time, developing regional carbon accumulation histories and carbon pool estimates, and projecting and quantifying overall peatland net carbon balance in a changing world. [ABSTRACT FROM PUBLISHER]