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This paper presents the results of a study on peat deposits and radiocarbon dating of basal peat horizons in 43 peatlands located on three key sites within Meshchera Lowlands and Moksha Polesie. Peatlands formed by upland paludification processes and located on watersheds and terraces rising above floodplains were selected for the analysis. The obtained data indicate that the peatland formation process has been ongoing in these regions throughout the entire Holocene epoch and that this process has been affected by the fire regime in the area. In periods with higher wildfire frequencies (8800–5800 and 4200–3200 calendar years BP), changes in the water balance on flat and poorly drained plains occurring after the destruction of forest stands intensified the waterlogging processes. [ABSTRACT FROM AUTHOR]

This paper explores how significant are the ecological and climatic variables to influence the stable isotopes of guanacos. Lama guanicoe bone collagen carbon and nitrogen stable isotope ratios are assumed as a macro regional average value in west Argentina, mostly as a baseline to model archaeological human diet. If stable isotopes on mammals reflex ecology and climate, we need to know how those variables influence mammals bone stable isotope ratio. This paper analyses the 13C/12C and 15 N/14N ratio on bone collagen on 122 guanacos from Northwest Patagonia during the Holocene. The results confirm significant variation in both isotopes between Monte and Andean-Patagonian specimens. Guanacos from Monte shows higher δ13C and δ15N than those from Andean-Patagonian. Temporal trends indicate variation through Holocene but this variation is not spatially homogeneous. In this paper we suggest that Medieval Climatic Anomaly had stronger effect in Monte desert than in Patagonia desert, generating driest and/or hottest conditions between 1250 and 600 years BP. Those variations need to be considered to reconstruct human diet at least during the second part of the Holocene. [ABSTRACT FROM AUTHOR]

The tropical Asian regions are particularly prone to catastrophic droughts due to high temperature and evaporation and their sensitivity to variable oceanic‐atmospheric circulation. The extent to which future global warming may intensify droughts in this populous region is a matter of utmost concern. Palaeoclimatic data can help inform scientists learn more about the temporal patterns and drivers of monsoon change over geological timescales. In this paper, we present a new 8,200 year biomarker record preserved in the annually laminated sediments of Maar Lake Twintaung, Myanmar. The δ13C27‐35 sedimentary record is mainly derived from leaf wax lipids in the lake catchment, which is presently dominated by C3 vegetation in the modern lake catchment. The δ13C27‐35 is mainly regulated by plant physiological and biochemical responses to drought stress and, as such, can be used as a proxy of past changes in moisture. The δ13C27–35 record reveals distinct decadal‐to‐centennial‐scale droughts superimposed on a trend of gradually decreasing summer monsoon intensity from the mid‐Holocene to late Holocene. Within the limits of the dating uncertainties, these decadal‐to‐centennial‐scale droughts are found to be well correlated with the southward shift of the Intertropical Convergence Zone. It highlights thepimportance of the Intertropical Convergence Zone shift (tropical monsoon trough) in regulating monsoon rainfall in the region. In addition, most of the droughts are likely to be linked with active volcanism and solar minima and suggest a coupled process between external drivers and internal climate dynamics. Key Points: Leaf wax n‐alkanes record in varved sediment of Maar lake Twintaung, MyanmarThe result indicates distinct decadal‐to‐centennial‐scale droughts over the past 8.2 kaThe drought cycles link with the ITCZ shift, solar and volcanic eruption [ABSTRACT FROM AUTHOR]

This paper presents geochemical and grain-size records since the early Holocene in core ECS0702 with a fine chronology frame obtained from the Yangtze River subaqueous delta front. Since ~9500 cal yr BP, the proxy records of chemical weathering from the Yangtze River basin generally exhibit a Holocene optimum in the early Holocene, a weak East Asian summer monsoon (EASM) period during the middle Holocene, and a relatively strong EASM period in the late Holocene. The ~8.2 and ~4.4 cal ka BP cooling events are recorded in core ECS0702. The flooding events reconstructed by the grain-size parameters since the early Holocene suggest that the floods mainly occurred during strong EASM periods and the Yangtze River mouth sandbar caused by the floods mainly formed in the early and late Holocene. The Yangtze River-mouth sandbars since the early Holocene shifted from north to south, affected by tidal currents and the Coriolis force, and more importantly, controlled by the EASM. Our results are of great significance for enriching both the record of Holocene climate change in the Yangtze River basin and knowledge about the formation and evolution progress of the deltas located in monsoon regions. [ABSTRACT FROM AUTHOR]

The englacial stratigraphic architecture of internal reflection horizons (IRHs) as imaged by ice‐penetrating radar (IPR) across ice sheets reflects the cumulative effects of surface mass balance, basal melt, and ice flow. IRHs, considered isochrones, have typically been traced in interior, slow‐flowing regions. Here, we identify three distinctive IRHs spanning the Institute and Möller catchments that cover 50% of West Antarctica's Weddell Sea Sector and are characterized by a complex system of ice stream tributaries. We place age constraints on IRHs through their intersections with previous geophysical surveys tied to Byrd Ice Core and by age‐depth modeling. We further show where the oldest ice likely exists within the region and that Holocene ice‐dynamic changes were limited to the catchment's lower reaches. The traced IRHs from this study have clear potential to nucleate a wider continental‐scale IRH database for validating ice sheet models. Plain Language Summary: Ice‐penetrating radar is widely used to measure the thickness of ice sheets, critical to assessments of global sea level rise potential. This technique also captures reflections from chemical contrasts within the ice sheet, caused by the atmospheric deposition of conductive impurities, known as "internal reflection horizons" (IRHs) that can be traced over large distances. As these deposits are laid down in distinct events, most IRHs are isochronous age tracers and contain valuable information on past ice sheet processes. In this paper we trace and place age constraints on stratigraphic horizons across a large portion of the West Antarctic Ice Sheet, including regions where fast ice flow has disrupted the ice sheet stratigraphy. The resulting data set allows us to identify where the oldest ice is buried in the study region and provides evidence that flow of the ice sheet interior has been stable during the Holocene. Our results can be used to test the performance of ice sheet models, which seek to simulate the response of ice sheets to long‐term environmental change. Key Points: We measure and date individual isochronal radar internal reflection horizons across the Weddell Sea sector of the West Antarctic Ice SheetHorizons dated to 1.9–3.2, 3.5–6.0, and 4.6–8.1 ka are widespread and linked to previous radar surveys of the Ross and Amundsen Sea sectorsThese form the basis for a wider database of ice sheet architecture for validating and calibrating ice sheet models of West Antarctica [ABSTRACT FROM AUTHOR]

In this paper, grain‐size records of 128 surface samples and six sediment cores retrieved from freshwater marshes across the Sanjiang Plain were employed to reconstruct the marshes' hydrological variation during the Holocene and to discuss its links to the East Asian summer monsoon (EASM) variation. The grain‐size hydrological significance for the marshes' deposits was first interpreted by quantitative analyses of 128 modern samples. The results indicate that the sand fraction exhibits a higher level significance to modern water‐level conditions than other grain‐size parameters. Thus, the sand accumulation rates of the six cores were calculated and employed to reconstruct the Holocene hydrological regime of the marshes on the plain. Based on the cluster analysis, it can be identified that three higher water‐level stages occurred during 6.2–5.6 thousand yr BP, 5.6–4.5 thousand yr BP, and 2.8–2.4 thousand yr BP, whereas four lower water‐level stages occurred during ~8.0–6.2 thousand yr BP, 4.5–2.8 thousand yr BP, 2.4–0.7 thousand yr BP, and 0.7–0 thousand yr BP, respectively. Considering the prevalent monsoon climate on the modern Sanjiang Plain, it is reasonable to believe that the local water‐level fluctuations were mainly regulated by the EASM variation rather than local factors including flooding, waterway modification, depression infilling, and human activities. The higher water‐level stages were linked to a stronger EASM and vice versa. This study provides essential background datasets for understanding the potential controls on the marsh development and degradation on the Sanjiang Plain. [ABSTRACT FROM AUTHOR]

The southern lowlands of Papua New Guinea (PNG) are biogeographically distinct. Vast tracts of savanna vegetation occur there and yet most palaeoecological studies have focused on highlands and/or forest environments. Greater focus on long-term lowland environments provides a rare opportunity to understand and promote the significance of local and regional savannas, ultimately allowing non-forested and forested ecosystem dynamics to be compared. This paper examines palaeoecological and archaeological data from a lowland open savanna site situated on the south-central PNG coastline. The methods used incorporate pollen and micro-charcoal analyses, artefact recovery and sediment descriptions. We conclude with an environmental model of sedimentation and vegetation change for the past c. 5,800 years, revealing a mid to late Holocene savanna interchange between herbaceous and woody plant growth, with fluctuating fire occurrence increasing toward the present day. Increased silt deposition and modified regional hydrology are also recorded. Environmental changes correspond in timing with the start of permanent settlements and human use of fire. In particular, landscape burning for hunting and gardens for agriculture have helped create the open ecosystem still evident today. [ABSTRACT FROM AUTHOR]

Although general trends in transgressive to highstand sedimentary evolution of river‐mouth coastlines are well‐known, the details of the turnaround from retrogradational (typically estuarine) to aggradational–progradational (typically coastal/deltaic) stacking patterns are not fully resolved. This paper examines the middle to late Holocene eustatic highstand succession of the Po Delta: its stratigraphic architecture records a complex pattern of delta outbuilding and coastal progradation that followed eustatic stabilization, since around 7·7 cal kyr bp. Sedimentological, palaeoecological (benthic foraminifera, ostracods and molluscs) and compositional criteria were used to characterize depositional conditions and sediment‐dispersal pathways within a radiocarbon‐dated chronological framework. A three‐stage progradation history was reconstructed. First, as soon as eustasy stabilized (7·7 to 7·0 cal kyr bp), rapid bay‐head delta progradation (ca 5 m year−1), fed mostly by the Po River, took place in a mixed, freshwater and brackish estuarine environment. Second, a dominantly aggradational parasequence set of beach‐barrier deposits in the lower highstand systems tract (7·0 to 2·0 cal kyr bp) records the development of a shallow, wave‐dominated coastal system fed alongshore, with elongated, modestly crescent beaches (ca 2·5 m year−1). Third, in the last 2000 years, the development of faster accreting and more rapidly prograding (up to ca 15 m year−1) Po delta lobes occurred into 30 m deep waters (upper highstand systems tract). This study documents the close correspondence of sediment character with stratal distribution patterns within the highstand systems tract. Remarkable changes in sediment characteristics, palaeoenvironments and direction of sediment transport occur across a surface named the 'A–P surface'. This surface demarcates a major shift from dominantly aggradational (lower highstand systems tract) to fully progradational (upper highstand systems tract) parasequence stacking. In the Po system, this surface also reflects evolution from a wave‐dominated to river‐dominated deltaic system. Identifying the A–P surface through detailed palaeoecological and compositional data can help guide interpretation of highstand systems tracts in the rock record, especially where facies assemblages and their characteristic geometries are difficult to discern from physical sedimentary structures alone. [ABSTRACT FROM AUTHOR]

Abstarct: Jeju Island, which lies on the continental shelf in the southern Korean Peninsula, is the emergent portion of a basaltic volcanic field that has erupted since the Early Pleistocene (ca. 1.8 Ma). Volcanic activity that continued into historic times (ca. 1 ka) formed an elongated shield with a central edifice (Mt. Halla) and more than 300 monogenetic cones and rings. The establishment of a temporal framework for Jeju volcanism, particularly during the Late Pleistocene and Holocene activities, requires geochronological tools other than radiometric dating techniques, which are based on parent-daughter isotope pairs with geologically long half-lives, such as 40Ar/39Ar dating. In this study, we conducted quartz optically stimulated luminescence (OSL) dating of palaeosols intercalated with basaltic lava flows and scoria deposits, presumably ejected from three monogenetic volcanoes (Cheoreum, Darangsh and Dunjibong volcanoes) in the northeastern part of the island. Quartz extracts from the palaeosols had moderate to dim sensitivity to optical stimulation, but several prerequisite tests of the measurement protocols for equivalent dose estimation were successful. The coarse (63–250 μm) and fine (4–11 μm) quartz fractions yielded continuous wave (CW)-OSL ages of 19.9–7.0 and 18.6–6.7 ka, respectively, both of which were broadly consistent with the radiocarbon dates (10245–7440 Cal yr BP). These ages indicate that lava flows and scoria deposits covering the palaeosols are younger than ~7 ka. The pulsed OSL signals in coarse quartz extracts from the palaeosols suffered from poor counting statistics, thus it is recommended that they not be applied solely (i.e., without any other absolute ages to compare) to dating dim samples. From one of the sites investigated here, the averaged sedimentation rate of the palaeosol is estimated to be ~0.05 mm/yr, based on stratigraphically consistent CW-OSL ages. The OSL ages presented in this paper, together with previous OSL and radiocarbon ages, confirm that Jeju volcanic island was regionally active during the Holocene. [ABSTRACT FROM AUTHOR]

The study of dental morphology has proven useful for reconstructing the biological profiles of ancient populations. In this work, we present the results obtained by analysing dental non-metric traits in many of the most important Mesolithic burial contexts from the Iberian Peninsula. Currently, a substantial debate is underway regarding the relationship between the different geographical areas of the Peninsula and their different chronological moments. This paper is based on a sample consisting of a minimum number of 437 previously unpublished individuals from 11 Mesolithic and Neolithic sites, whose data were compared with Italian Mesolithic and Neolithic samples and posterior Iberian groups. We analysed these data by chi-squared analysis and by calculating the mean measure of divergence biological distance measure. There were no significant differences among the different regional groups from the Iberian Mesolithic. Moreover, the Iberian Mesolithic samples differ significantly from the Italian samples. In addition, although certain Neolithic samples differ from the hunter-gatherer profile, it seems that they received important biological influence from Mesolithic groups from the Iberian Peninsula, which varies with geography, since the farmer groups from the Mediterranean area are the most distinct from the previous hunter-gatherers. Our results suggest a common biological origin for all the Iberian Mesolithic assemblages, which probably originated during the Last Glacial Maximum. In addition, this profile differs from the one observed in Italian coetaneous groups. Finally, similar to the latest aDNA studies, this study suggests that the Neolithization process of the Peninsula was heterogeneous. [ABSTRACT FROM AUTHOR]

Cyclic facies variations in shallow‐water carbonate platforms often show repetitive facies patterns that are frequently interpreted to reflect the sedimentary response to variations in sea‐level related to changes in climate linked to orbital variations, the Milankovitch frequencies. Whether these shallow‐marine carbonates represent a complete infill of accommodation space, or are subtidal cycles, has been discussed in numerous papers. The extent to which the thickness of a single depositional cycle is a direct measure of the amplitude of relative sea‐level change is not fully understood. New shallow seismic data from Great Bahama Bank reveal that accommodation space created during the Holocene sea‐level rise is not filled in a predictable way. Three seismic horizons were identified: the seabed, the Pleistocene top, and a horizon within the Pleistocene. Depth surface and thickness maps of the Holocene and Pleistocene layers were combined with 326 in situ water‐depth measurements to assess the upper limit of the present accommodation space. The analysis showed that accommodation space and Holocene sediment thickness, and water depth are not correlated. In addition, the actual water depth and inner platform facies distribution showed no straightforward link. The energy distribution across the shallow‐water platform appears to control the facies type rather than water depth. Mud‐dominated sediments prevail in shallow low‐energy areas protected by a topographic barrier, whereas mud‐free coarse‐grained sediments mainly occur in deeper areas with hydrodynamic energy induced by strong tidal currents, ocean water influx, and winds. Hence, the uneven energy distribution not only results in unpredictable differences in the carbonate‐cycle thickness on the platform but also to a water depth independent facies distribution pattern within the inner platform. Therefore, care should be taken when deducing sea‐level signals from inner platform facies distribution and sediment thickness patterns on ancient platforms. [ABSTRACT FROM AUTHOR]

The Yangtze Delta is one of the economically most developed areas in China. It is located in the eastern China monsoon region. Archaeological excavations and environment-archaeology studies over many years in this region provide exceptional information about climate changes, development of human civilization and also human-environment interactions. Archaeological excavations made in the study region reveal that the development of Neolithic cultures is not continuous, which may be a result of extreme climatic events. The analysis of14C-dated buried paleotrees, peat and shell ridges show the rise and fall of human civilization in the study area. The research results presented in this paper confirm that human civilization collapsed six times in the Yangtze Delta, matching six high sea level epoches, peat accumulation and buried paleotrees formation periods respectively. This indicates that human activities in the Yangtze Delta are controlled by local climate changes and changing hydrological conditions. The collapse of the Liangzhu culture (5000 aBP-3800 aBP) in about 4000 aBP, after a tremendous flooding event, followed by a relatively backward Maqiao culture (3800 aBP-3200 aBP) confused researchers and aroused their great interest. The research results in this paper show that the collapse of the Liangzhu culture is a result of several factors, for example war and food shortage, but the flooding event occurred in the late Liangzhu culture epoch is the main factor therein. [ABSTRACT FROM AUTHOR]

The province of Namibe, in south-western Angola, is rich in rock art, which is distributed throughout the region, from the municipality of Camucuio, with its Cipopilo sites, to the Caraculo area, which has the largest number of shelters with rock art. The distribution extends throughout the region, including the municipality of Virei, where the Citundu-Hulu shelter stands out, and the commune of Iona, with the Monte Negro rock art site. To date, the Caraculo region has the largest number of rock art sites identified in Angola. In this paper, we will discuss the general state of rock art studies in Namibe province and, of the various shelters found in the region. We will focus our study on four new sites firstly published in this paper, as they are a good illustration of the diversity of rock art in the region: Muliolila, Múcua II, Kandombolo and Cikotoue. These four shelters were subjected to a digital documentation protocol that is fundamental to the preservation and understanding of these archaeological sites. The methodology involved the application of a digital documentation protocol that included digital photography of the site, panels, figures and surrounding landscape, digital image processing, enhancement of the visualisation and interpretation of the rock art images using DStretch® software, and digital tracing using Adobe Photoshop© software. This documentation protocol will be used not only to provide accurate and up-to-date information about the site (thus raising awareness of the cultural and historical importance of these sites), but also to identify hazards and threats that may affect the site, to monitor possible damage and to take measures to protect the site. The motifs represented are very diverse, emphasizing zoomorphic figures such as antelopes, cats and serpentine figures, anthropomorphic forms, geometric forms (simple lines, combined lines, and circular forms) and indeterminate figures. The figures are both monochromatic and bichromatic, with white, black and red being the shades that can be observed (although these vary within each colour). The predominant technique is finger painting. Hunting scenes can be seen, either in isolation or in combination. One suggests that there may be indications that figures were made by at least two culturally distinct groups, even if in this paper the authors do not present any scientific proof for this statement but only different characteristics of the rock art. The rock art sites in the Namibe are of great cultural and historical importance, both for Angola and the world. They provide valuable information about the lives and traditions of the peoples who created them and help to promote awareness and conservation of Angola's cultural heritage. It is essential that intensive documentation and awareness of the importance of this Angolan rock art heritage be promoted and practiced on a large scale. [ABSTRACT FROM AUTHOR]

Anthropocene, geology, Holocene, human impact, stratigraphy The "Anthropocene" is most useful as an informal concept Keywords: Anthropocene; geology; Holocene; human impact; stratigraphy EN Anthropocene geology Holocene human impact stratigraphy 453 454 2 05/09/23 20230501 NES 230501 The "Anthropocene" (Crutzen & Stoermer, [4]; Crutzen, [3]) concept has rapidly gained prominence in recent years in both public narratives around the climate and environmental crisis, and academic discourses across a range of disciplines - the latter being demonstrated by the multitude of papers published discussing various aspects of the proposed new geological epoch (e.g. Waters et al., [14]). [Extracted from the article]

This paper presents the results of a study on traces of ancient earthquakes in the lake bottom sediments of eastern Fennoscandia (Kola region and Karelia). Based on the sediment cores from six lake basins located within large active structures of the region, consideration is being given to the most typical features of sedimentation affected by neotectonic movements of the Earth’s crust. The data presented here provide lithological-stratigraphical, paleobotanical and chronometrical evidence for lakes. The paper causes and mechanisms of formation of seismic structures in bottom sediments and their distinction from deformations of another origin.Generalized earthquake history in provided an opportunity to organize the existing information on the time of paleoearthquake manifestations and distinguish three active periods in paleoseismicity. These are Late Glaciation-Early Holocene marked by the most rapid uplift after the retreat of the last ice sheet (13500–8100 cal yr BP), Middle Holocene (6800–6600 cal yr BP), and Late Holocene (3100–200 cal yr BP). The results of this study showed that the number and intensity of seismic events changed at different stages of sedimentation. Since the Younger Dryas, fault zones (or their segments) have been repeatedly activated. Combined with the data on paleoseismicity in adjacent parts of Fennoscandia, our studies indicate an irregular pattern of the Late Pleistocene-Holocene seismic activity in stable areas formerly covered by glaciers. The obtained data make further adjustments to the neogeodynamic and seismic estimates of intraplate areas.

To better understand long-term precipitation changes in arid Central Asia, reconstruction of past precipitation is critical. This paper analyzed the core sediments of Balikun lake in eastern Xinjiang. We analyzed 200 pollen samples, combined with 441 surface pollen samples and a radiocarbon chronology, using the Weighted Averaging Partial Least Sequence (WA-PLS) method, to characterize the Holocene high-resolution precipitation change process in Balikun basin. And, Combined with the vegetation types reconstructed by biome method, we discussed the landscape evolution of Balikun basin. Results show that the mean annual precipitation during the Holocene can be broken into three phases: Early Holocene (11,750–8030 cal yr B.P.), which averaged about 130 mm; Middle Holocene (8030–4420 cal yr B.P.), which averaged about 250 mm; and Late Holocene (4420–0 cal yr B.P.), which averaged about 210 mm. The vegetation changed from desert to steppe during the Holocene, and the wetlands gradually expanded, which was mainly informed by precipitation and glacial melt water. [ABSTRACT FROM AUTHOR]

Shaw, C.E. and Benson, L., 2015. Possible tsunami deposits on the Caribbean coast of the Yucatán peninsula. The western Caribbean Basin is notable for its tectonic stability. It has experienced no historical earthquakes or the tsunami that sometimes accompany them. This paper describes a single, wedge-shaped, boulder-covered, coastal berm on the Yucatán coast of México that stretches unbroken for 50 km across a coastal segment characterized by rocky headlands that alternate with crescent beaches. The remainder of the 350 km of Yucatán coast consists mostly of mangrove that extends 1 to 30 km inland, often behind long, sandy beaches. On the headlands, the surface of the berm is densely paved with boulders-large boulders on its seaward face and smaller boulders and cobbles on its gently sloping inland surface. The top of the berm reaches an elevation >4 m, above the reach of all but the largest modern storm waves. Berm sediments on the headlands consist of two distinct layers of unbedded coarse sand with numerous randomly distributed boulders and cobbles in the lower layer and a crudely textured gravel and sand layer above. At first glance the two layers appear to be separated by 20 cm of white sand above a thin, discontinuous zone of dark, greyish sand that contains isolated balls and smears of black organic material, apparently derived from a soil, or possibly leaf litter. The berm and its associated boulders track the modern coastal morphology in precise detail as it follows the form of modern headlands, bays, and transcoastal channels, indicating that deposition took place after development of the present coast. The berm sediments record two or three large waves, depending on whether the wave that deposited the boulder pavement is regarded as part of the second wave or as a separate wave. Radiocarbon dating indicates that at least one wave struck the coast approximately 1500 years before present. Minimum wave run-up exceeds 4 m above present sea level, and inland inundation reached 400 m along bays and transcoastal channels. The position and elevation of the berm, its lack of well-developed internal bedding, the paving of the berm surface by thousands of boulders, and its 400-m extent inland along channels and bays are features commonly associated with tsunami. However, some recent studies conclude that all of the features listed also can be produced by mega-hurricanes. Placed in the context of our literature search of the recent history of hurricanes and tsunami in the Caribbean Basin, we conclude that the single berm on the Yucatán coast represents an anomalous event for this area and that the berm sediments bear a strong similarity to descriptions of sediments from some historical tsunami and are unlike sedimentary features associated with historical hurricanes. [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]

By combining a multidisciplinary approach and an intensive program of scientific techniques, this paper provides a comprehensive overview of salt production at the Villafáfila lagoons (Zamora, Spain) in prehistoric times. During the Late Chalcolithic and the Early/Middle Bronze Age salt was obtained by boiling brine from salt lagoons. In many parts of western and central Europe at the time the standard procedure for forcing evaporation usually involved the use of crudely fired clay vessels (briquetage) to concentrate brine, and then to mould salt. We suggest that the methods during the final stages of the process differed at Villafáfila, having found evidence of basketry and textiles, which may have been used in the step of crystallization/transport of salt in cake, instead of the small ceramic salt moulds which would be expected in such sites. The role of salt within the socioeconomic setting of the 3rd and 2nd millennia BCE in Central Iberia is also assessed. It is argued that the production and distribution of salt contributed significantly to the political economy, as elites controlled this activity, supporting the idea that salt was a prestige good that contributed to the accumulation of wealth. There is also evidence of ritual practices in the salt-processing areas, as human burials and animal sacrifices have been documented in the excavated sites. • Archaeological evidence shows the production of salt at the Villafáfila lagoons by the late 3rd millennium BCE, during the Beaker period. • Brackish water was boiled in large ceramic vessels supported by clay or stone pedestals. • Techniques evolved during the Early Bronze Age, when pedestals were replaced by clay-walled kilns. • Absence of genuine briquetage, and of small ceramic pots used as salt moulds. • Possible use of baskets and textiles sacks as moulds. [ABSTRACT FROM AUTHOR]

Bats are a highly diversified order of mammals found all over the world; however, their population size and distribution are decreasing rapidly in Europe nowadays. The study of ancient bat populations by means of their fossil record is a valuable source of contextual information for modern bat conservation studies. This paper is a comprehensive review of published bat records in the Iberian Peninsula and the Balearic Islands through Quaternary times, representing the first attempt to update and standardize the knowledge of chiropters in southwestern Europe during this time period. The main goal is to identify changes in bat assemblages that might be correlatable to palaeoclimate and palaeoenvironmental changes. Our data show that the Quaternary record of bats in the area is fragmentary and strongly dependent on the presence of karstic cavities. Thus, a strong preservation bias towards colonial cave-dwelling bats exists, and species with alternative ecological requirements are under-represented. Nevertheless, this work reveals that most of the bats inhabiting the area today were already present in the region from at least the Middle Pleistocene. Interestingly, we observe a frequent association between certain cave-dwelling bats (i.e., Rhinolophus ferrumequinum , Miniopterus schreibersii , Myotis myotis and M. blythii) that is still observed in many caves today; this reflects a stable ecology that has remained undisturbed despite past climatic changes. Within the well-documented periods at the end of the Late Pleistocene and the Holocene, a reduction in some common components of Quaternary assemblages (Rhinolophus species and M. schreibersii) is observed, coinciding with the Late Glacial Maximum and the Northgrippian Neoglacial (a cooling event in the Holocene). Finally, the Balearic record shows interesting palaeobiogeographical characteristics, including some eastern taxa absent in the Iberian Peninsula (Rhinolophus variabilis and R. cf. blasii) as well as an unusual abundance of Rhinolophus hipposideros. • Most extant bats in the Iberian Peninsula were already present there ca. 600 ka. • A strong bias towards colonial, cave bats counting exists within the fossil record. • Three Mediterranean cave bats associate stably despite Quaternary climate shifts. • The Last Glacial Maximum and the Northgrippian Neoglacial events left a mark. • Two oriental taxa and higher reports on Rhinolophus for the Balearic fossil bats. [ABSTRACT FROM AUTHOR]

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]

Daily insolation at a given latitude is often used in the explanation of the long-term variations of paleoclimate records. However, the length of astronomical seasons, which has been paid less attention, could also be important. This paper provides an original calculation of the length of these seasons using the eccentric anomaly. The past and future long-term variations as well as the spectral characteristics of the length of astronomical seasons, of the total and average insolation over the astronomical seasons and of the caloric insolation are shown and compared. The length of astronomical seasons is only a function of climatic precession. The total irradiation for a given latitude and an astronomical season is mainly a function of obliquity except that it is mainly a function of eccentricity in a latitudinal band that is season dependent and from where the phase between obliquity and total irradiation reverses (e.g. ∼11.5°N for the astronomical northern hemisphere summer half-year). The spectral characteristic of the mean insolation over the astronomical summer half-year varies in latitude and time. It contains stronger obliquity signal in high latitudes than in low latitudes, but the obliquity signal already gets very weak at 45°N/S leaving the dominance of climatic precession between 45°N and 45°S. The variation of the mean summer half-year insolation over the last 1 Ma is characterized by a Mid-Brunhes transition at ∼450 ka BP, with a dominant role of climatic precession at all latitudes before ∼450 ka BP but significantly enhanced role of obliquity in high latitudes after this time. The simultaneous weakening of the variations of climatic precession and obliquity around 800 ka ago, a time corresponding to the Mid-Pleistocene Transition, leads to weak variations in both total and mean seasonal insolation. The insolation of a specific case, the Holocene, is finally discussed. Depending on the sensitivity to different types of insolation, different climate variables and regions could show different evolution and trend during the Holocene. • An original calculation of the length of the astronomical seasons is provided. • Precession and obliquity contribute differently to the length of astronomical seasons and to different insolation metrics. • Distinctive variations of total and mean seasonal insolation characterize the Mid-Brunhes and Mid-Pleistocene transitions. • Different insolation metrics display different trend over the Holocene. [ABSTRACT FROM AUTHOR]

Formation and evolution processes of natural tombolos involve many interrelated geomorphological, sedimentary, oceanographic and anthropogenic factors, making their measurement and simulation an extremely difficult task. The present study attempts to fill this knowledge gap by detecting the natural tombolos in Greece, formed in the current sea level, through the statistical analysis of their morphometric and socio-environmental parameters. In addition, the long-term evolution of these coastal depositional landscapes has been determined by comparing old aerial photos taken in 1945 or 1960 and recent satellite images taken from 2020 to 2022. Two thirds of the twenty tombolos studied are subject to erosion, while eight are sporadically destroyed and turned into salients. The Greek tombolos are mildly or heavily exploited for touristic purposes, and fourteen of them are protected by national and international environmental laws. Future studies need to focus on the unstable type of these coastal landforms that are modified from tombolo to salient and vice versa to obtain helpful information about the morphodynamic conditions necessary for their evolution. [ABSTRACT FROM AUTHOR]

The stable carbon isotope composition of total organic matter (δ13Corg) has been utilized in aeolian sediments, serving as an indicator for reconstructing terrestrial paleoenvironments. The Qinghai Lake (QHL) Basin is a climate-sensitive region of significant importance in paleoclimatic reconstruction. However, the reconstructed climatic variations based on δ13Corg in aeolian sediments in the QHL Basin in the northeastern Qinghai-Tibet Plateau (QTP) are lacking, and their paleoclimatic significance remains poorly understood. By conducting δ13Corg measurements on the Niaodao (ND) aeolian profile near QHL, we reconstructed the paleoclimate changes of 11 ka–present. The variation range of the δ13Corg values in the ND profile indicated the terrestrial ecosystems were not the sole contributor to lacustrine organic matter. The δ13Corg values are an indicator of historical temperature changes in the study area, exhibiting similar trends with the reconstruction of Chinese summer temperatures, East Asian air temperature, global temperature, and Northern Hemisphere summer insolation at 37° N. The temperature increased with high frequency and amplitude oscillations, with strong aeolian activity and low total organic carbon accumulation during the Early Holocene. The temperature was maintained at a high and stable level, with the weakest aeolian activity and intensified pedogenesis during the Middle Holocene. The temperature decreased at a high rate, with renewed aeolian activity and weak pedogenesis during the Late Holocene. [ABSTRACT FROM AUTHOR]

This study involves an investigation into the grain size distribution and provenance of the sand deposited near Zagreb (Croatia) in the riverbed of the regionally important, almost 1000 km long Sava River, which connects several SE European countries. Recent research in the study area has mainly focused on the deposits forming the Zagreb alluvial aquifer system, rather on the Sava River sediment deposited in its riverbed, which is the focus of this study. The grain size distribution results obtained by dry sieving and laser granulometry showed a predominately fine and medium sand deposition at riverbanks and sand point bars. Medium sand increased downstream towards the east, within the artificially more channelized riverbed in the urban area. Fine sand prevailed 50 km further downstream in a more meandering low-relief area, near the city of Sisak and Lonjsko Polje Nature Park. Provenance analysis showed predominately carbonate sand in the western part of the city of Zagreb, originating from distant (Alpine) and local (Medvednica Mt. and Samobor Hills) sources. More siliciclastic sand was deposited in the Sava riverbed in the middle and eastern parts of Zagreb, originating mainly from the Medvednica Mt. The prevailing siliciclastic sand further downstream of the Sava River is probably sourced from the Kupa River tributary. Although various studies of the Zagreb alluvial aquifer system have been conducted so far, this study represents a novelty in its investigation into the grain size distribution of the Sava riverbed sand itself, setting the foundations for investigations in the future. [ABSTRACT FROM AUTHOR]

Coastal regions are vulnerable to rising seas, increasing storm magnitude, and decimation of ecologically-fragile areas. Deltas are particularly sensitive to the balance between sea-level rise, land subsidence and sedimentation that determine relative elevation. Bangladesh has been highlighted as being at risk from sea-level rise. Integrating measurements from different methods can approach a more complete understanding of factors controlling areally and temporally varying subsidence rates. To augment our compilation of rates from stratigraphic wells, historic buildings, vertical strainmeters, RSETMH, and continuous Global Navigation Satellite System, we resurveyed 48 geodetic monuments in coastal Bangladesh ~18 years after the monuments were installed. A later resurvey of 4 sites showed that some sites with higher subsidence may be unstable, but we consider the subsidence pattern of all the sites. Sites with rates <2 mm/yr overlie thin (<35 m), sandy Holocene deposits located along interfluves between the main paleo-river valleys. As Holocene strata thicken seaward and become muddier, subsidence rates increase to 20-25 mm/y. Sites in incised valleys of the Ganges, Brahmaputra and Meghna Rivers, with Holocene sediments >100 m show subsidence rates of 20 ± 10 mm/y, with a slight seaward increase. Overall, subsidence rates increase with Holocene sediment thickness and the seaward shift from sandy to muddy sediments. Together with earlier measurements, we parse the different rates and mechanisms of subsidence. Earlier models show 2-3 mm/yr correspond to deep processes, such as isostasy. Within the shallow Holocene (<10 m), we estimate 5-8 mm/yr of subsidence from shallow, edaphic effects (tree roots, burrows, organic matter decomposition) and shallow (<10 m) sediment consolidation on short timescales. Below this, we estimate 3-6 mm/yr from compaction of the upper Holocene strata, with 2-5 mm/yr occurring in deeper Holocene strata. Subsidence rates in areas of active sedimentation, such as rice fields and mangrove forests, are greater than buildings and structures with deep foundations. Subsidence on timescales >300 y, which do not include edaphic effects, are up to ~5 mm/y. We note subsidence can be offset by active deltaic sedimentation, and does not necessarily indicate elevation loss. Collectively, the integration of these approaches allows us to begin quantifying the varied contributions to land subsidence from edaphic effects, Holocene sediment compaction, lithology, and time. Similar factors may contribute to the highly variable subsidence rates observed at other deltas worldwide. [ABSTRACT FROM AUTHOR]

Lakes are threatened by contemporary climate change and human activities. Paleohydrological records provide important evidence for developing scenarios for future changes in the availability of freshwater resources. This study presents a synthesis of a sedimentological, archeological, and chronological dataset collected from Lake Annecy (eastern France) to reconstruct a lake-level record documenting the whole Holocene. This dataset shows a pronounced minimum in the lake level during the Holocene thermal maximum (HTM) (ca. 9000–7000 cal BP), preceded by a general lowering trend (early Holocene), and followed by a general rising trend (Neoglacial). On both the millennial and centennial scales, the Lake Annecy record appears to match the regional pattern of Holocene lake-level fluctuations established for West-Central Europe. In agreement with other extra-regional paleoclimatic records, it shows the dominant influence of orbital forcing. The high magnitude of the lake-level lowering (more than 5 m) during the HTM, with a 2–2.5 °C difference between the HTM and the pre-industrial mean summer temperatures, suggests possible drastic lake-level lowering phases in the near future depending on the IPCC scenarios following climate change. This would mean dramatic impacts on human activities and the preservation of exceptional archeological remains in regional lake basins. [ABSTRACT FROM AUTHOR]

In order to understand the paleogeographic evolution of Viedma Lake (252 masl) sedimentary sequences with glaciolacustrine and lacustrine strata between 307 masl and 266 masl and bathymetric fluctuations between 27 ka. and 2.4 ka. were identified. The paleoenvironmental interpretation of the stratigraphic profiles was carried out based on the analysis of facies and their associations. The oldest age was recorded at 301 masl (27 ka) and the youngest corresponds to 266 masl (2.4 ka). The record of 27 ka was compared with another dated record of the Tar-San Martin Lakes basin showing that Viedma – Tar-San Martín Lakes were formed at similar ages. Taking into account that the deposits of Bahía Túnel are located at 266 masl and that the level of the lake would be above this height, it is proposed that this lake level would have restricted the movement of hunter-gatherer populations along the coast and to the west. From 2.4 ka on a new space started to be available for these populations broadening the wintering grounds (≤400 masl). The chronology of the archaeological record found in this new space fits the proposed paleogeographic evolution. This paper complements the research on the evolution of lacustrine systems in the Patagonian Mountain range and broadens the discussion of human mobility in the Viedma Lake basin during the Holocene. [ABSTRACT FROM AUTHOR]

The aim of this study is to assess the variability of the stable carbon and nitrogen isotope composition of herbivores -guanaco and huemul-in southern Patagonia. The study area extends from the eastern slopes of the Andes to the Atlantic Coast between 47° and 49° S. The ultimate aim of the research was to generate an isotopic ecology with an adequate spatial resolution that allows the incorporation and development of stable isotope studies in discussions of the population dynamics of hunter-gatherers in continental Patagonia. This paper presents the δ13C and δ15N values of 159 guanaco and huemul specimens, both modern and archaeological. This space was divided into three areas: Western area, Central Plateau and Eastern Area. Isotopic variability within groups was analyzed using the SIBER, from which the isotopic niches of the different groups are compared. The results show a spatial pattern of isotopic variability in herbivores, i.e. lower δ13C and δ15N values associated with forest environments in the western end of the transect and higher values, especially δ15N, towards the east, with maximum values observed near the Atlantic coast. Our results support the stated expectations on herbivore stable isotope composition variability and its association with environmental variables in a longitudinal transect across the southern Argentinean Patagonia. [ABSTRACT FROM AUTHOR]

This study investigates the sedimentological evolution of the South Danamandıra Lake (SDL) lake in Çatalca Peninsula, 70 km west of İstanbul, using Georadar data and multiproxy analyses of five sediment cores. The lake is a 1.3-m deep, endorheic freshwater peatland, heavily colonised by common reed (Phragmites sp.). The multiproxy core investigations include a lithological core description and environmental magnetism, physical properties (gamma density and magnetic susceptibility), geochemical elemental, pollen and radiocarbon dating analyses. The lithological sequence in the lake consists of an upper peat unit and a lower sand-silt-clay unit. The peat unit is characterized by lower magnetic susceptibility, density and lithophile elements (K, Fe, Ti, and Zr) concentrations than the sand-silt-clay unit. Overall interpretation of the multiproxy data and the age-depth model suggest that the SDL was formed in a shallow depression of a fluvial channel at ca 10.9 cal kyr BP, and became a eutrophic lake at 8.1 cal kyr BP during the early Holocene warm period. Redox-sensitive element (i.e. Mn) distribution and mineral magnetic properties indicate that the peat unit has accumulated under anoxic conditions below a thin oxic surficial layer. Increase in the Taraxacum, Asteraceae, and Poaceae pollen percentages, together with high siliciclastic inputs in the lake, indicate that anthropogenic influence in the area started at 5.4 cal kyr BP [ABSTRACT FROM AUTHOR]

This paper aims to contribute to the understanding of the Holocene evolution of the Cávado estuarine coastal system (Portugal) and the adjacent terrestrial areas, using a multidisciplinary approach, which includes geomorphology, sedimentology, palynology, radiocarbon and history. During the Early Holocene, the Cávado environment was characterized by the dominance of coarse sediments especially in the most westward areas, corresponding to fluvial energetic dynamics. During the Middle Holocene, the presence of wetlands dominated especially in the most sheltered areas. The pollen data reflect the predominance of forests during the initial phases of the introduction of agriculture, with a significant presence of humid forests. Between 4240 and 3980 cal BP, a sudden marine flooding took place over the peat. During the Late Holocene, there was a succession of low, high and again low energy fluvial environments in the eastward sheltered areas, while high energy dominated in the Fão channel entrance, with marine influence on the uppermost units. The pollen content reflects a situation of high human influence, with a poor representation of natural forests and a predominance of agrosystems, related to the rise of the Cávado estuary as a port during the heyday of the city of Braga during the Roman and Suevian periods, as described in historical texts and archaeological research. In connection with this growth, the pollen data show the existence of local Pinus plantations related to shipbuilding and repair in the port. During these times, the estuary was larger and open to the sea at Fão. After the 15th century, with the general silting of coastal areas, the inlet closed and the river mouth was displaced to the North. [ABSTRACT FROM AUTHOR]

Late Holocene environmental changes were examined in Dee Why Lagoon, New South Wales, based on the sedimentological, geochemical and geochronological analysis of six cores collected from the fluvial delta and lagoon basin. The lagoon formed about 7300–7200 cal yr BP, following the post-glacial marine transgression and establishment of a sand barrier. Infilling of the lagoon occurred at a rate of 0.09–0.15 mm/yr until about 3300–3200 cal yr BP, when the barrier closed, resulting in mostly freshwater conditions, as evidenced by a change from pyrite-rich units to sediment containing little sulfur and a lack of foraminifera. Sedimentation rates increased to 0.23 then 0.43 mm/yr until about 100 years ago. Post-European land clearance led to an increase in sedimentation rates to 1.0–1.3 mm/yr on the fluvial delta, which are lower than those from other wave-dominated estuaries in New South Wales as well as those estimated by previous studies in Dee Why Lagoon. Our study shows that the fluvial delta started forming much earlier than originally thought, based on results of radiometric dating, and confirmed using sedimentological and geochemical data, as well as a critical examination of historic aerial photographs. Human impact has resulted in an increase in heavy metal (Cu, Pb, Zn) and metalloid (As) concentrations in the recent sediment, most likely attributed to stormwater discharge. Pb and As concentrations are above the ANZECC high sediment quality guideline values at the site closest to the stormwater outlet, with As-based pesticides one of the possible sources. Using the mean enrichment quotient, which is based on normalised Cu, Pb and Zn concentrations over their normalised background concentrations, we show that the surface sediments in Dee Why Lagoon are severely enriched, reflecting the recent anthropogenic impact that has also led to an increase in sedimentation rates. [ABSTRACT FROM AUTHOR]

Mediterranean Africa forms a crucial junction between the wider Saharan zone and the rest of the Mediterranean. In contrast to its well-investigated history from the first millennium BC onward, its antecedent dynamics are very poorly understood, and deeper archaeological histories of the Mediterranean therefore remain unbalanced and incomplete. This paper draws on a new surge in data to present the first up-todate interpretative synthesis of this region's archaeology from the start of the Holocene until the threshold of the Iron Age (9600-1000 bc). It presents the evidence for climatic, environmental and sea-level change, followed by analysis of the chronological and spatial patterning of all radiocarbon dates from Mediterranean Africa, brought together for the first time. The principal exploration then divides into three phases. During Phase 1 (9600-6200 bc) diverse forms of hunting, gathering and foraging were ubiquitous. Phase 2 (6200-4000 bc) witnessed more continuity than elsewhere in the Mediterranean, but also the widespread uptake of domesticated livestock and gradual evolution of herding societies, as well as limited enclaves of farming. Phase 3 (4000-1000 bc) has been least explored, outside developments in Egypt; in the east this phase witnessed the emergence of fully nomadic and transhumant pastoralism, with political superstructures, while trajectories in the west remain obscure, but in parts of the Maghreb suggest complex possibilities. Contacts with the Mediterranean maritime world grew during the third and second millennia bc, while interaction to the south was transformed by desertification. Understanding how the southern Mediterranean shore was drawn into Iron Age networks will require much better knowledge of its indigenous societies. The present constitutes a pivotal moment, in terms of accumulated knowledge, pathways for future investigation and engagement with a challenging current geopolitical situation. [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]

The Holocene hydrological regime on the Heixiazi Island is critical for understanding the evolution of the East Asian summer monsoon (EASM) for the island's climate-sensitive location on the northern fringe of the EASM domain. In this paper, a marsh depression on the central island was selected to reconstruct the locally hydrological variation and to discuss its indications for the Holocene EASM evolution. This work is based on multi-proxy (magnetic susceptibility, grain size, loss-on-ignition, and carbonate content) analyses of 22 modern sedimentary samples with a water-level gradient of 0–66 cm and 100 cored sedimentary samples covering last ~ 9.0 ka BP. The proxies' hydrological significance was previously interpreted by the 22 modern samples using linear regression equations to construct their relationships to water-level changes. Among these proxies, the magnetic susceptibility, carbonate content, as well as the Md and sand fraction of grain size exhibit high-level relationships against the water-level changes with R2 > 0.6. Thus, these four proxies' linear-regression equations were selected and used on the 100 cored samples, and the Holocene water-level changes in the studied depression were quantitatively reconstructed. It shows that two relatively high water-level stages with strengthened EASM occurred during 8.0–4.5 ka BP and 3.0–1.4 ka BP, which were alternated by three low water-level stages with declined EASM during ~ 9.0–8.0 ka BP, 4.5–3.0 ka BP, and 1.4–0 ka BP, respectively. Among these fluctuations, the highest water-level stage with most strengthened EASM which is defined as the Holocene Monsoon Maximum occurred during 6.4–4.5 ka BP. Such a new evolution pattern of the EASM can be further supported by a large variety of records from monsoon-margin regions. We suggest the Holocene EASM evolution was generally associated with the thermal conditions in both the inner Eurasia landmass and the West Pacific Ocean, with an exception of the weak EASM before 8.0 ka BP due to the enhanced Siberia High with the dominance of the Eurasia ice sheet in the early Holocene. [ABSTRACT FROM AUTHOR]

This paper presents a reconstruction of the Holocene dynamics of forest fires and their influence on vegetation in the central part of Meshcherskaya Lowland. The studies are based on macrocharcoal and pollen analyses and radiocarbon dating of peat deposits from the Studencheskoe peatland. According to the results, changes in the structure of the plant cover were largely determined by the fire regime during the Holocene. In the period of high forest-fire intensity (∼9200–6400 calendar years BP), the study area was occupied by birch-pine forests. The role of spruce and broad-leaved species in forest stands was increased in the period with a low frequency of forest fires (∼6400–1400 calendar years BP). The influence of fires on vegetation increased after 1400 calendar years BP due to human impact. The results show that periods of increased fire frequencies occurred before the human occupation of the area and were determined by climatic causes. [ABSTRACT FROM AUTHOR]

Copyright of Azania: Archaeological Research in Africa is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents new marine evidence of Lateglacial and Holocene environmental changes in the western part of Limfjorden, and provides a review of the geological history/development of this part of northern Jylland, Denmark. Lateglacial clay without fossils is widespread in the region and is probably a glaciolacustrine deposit. Limfjorden began to form as a strait in the Early Holocene due to rising relative sea level and the oldest marine shells are dated to c. 9300 cal. years BP. We propose a new relative sealevel curve for the region based on new and published data, which appear to confirm that the relative sea-level change was not extremely rapid, which was suggested earlier. During the Mid-Holocene a wide connection existed from the western part of Limfjorden to the North Sea in the west and more narrow connections existed between Limfjorden and Skagerrak in the north. The marine fauna included several species that indicate warmer and more salty waters than at present. Gradually, the connections to the North Sea and Skagerrak closed due to long-shore sediment transport and deposition of aeolian sand combined with a fall in the relative sea level during the Middle- to Late Holocene. During the Viking Age, 800-1050 CE (Common Era), the western connection to the North Sea was still open, but around 1200 CE it was closed by a coastal sandy barrier and the western part of Limfjorden became brackish. The coastal barrier was flooded on several occasions but soon formed again. After 1825 CE the western connection from Limfjorden to the North Sea has been maintained artificially. [ABSTRACT FROM AUTHOR]

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ABSTRACT In this paper we identify four 'revolutions' that in our view have shaped the study of sea-level changes in recent decades. (i) The search for 'eustasy'. One of the most hotly debated issues in the 1960s is still relevant as models of glacial isostatic adjustment (GIA) require input of the amount of meltwater transferred to the world's oceans following the demise of the large Pleistocene ice sheets. (ii) Resolution of sea-level archives. All sea-level archives have limitations in their resolving power but are we willing to define these? From studies of salt-marsh deposits and corals it is highly likely that climate-driven metre-scale sea-level fluctuations have not occurred during the middle and late Holocene. (iii) Rapid sea-level changes. Improved coring technology has resulted in the suggestion of meltwater pulses during the last deglaciation. Low-frequency high-magnitude events have been documented along seismically active shorelines and provide information on seismic hazards and storm impacts. (iv) Merging of empirical sea-level investigations and models. Much sea-level research in the past two decades has embraced the integration of models and field-derived data, providing testable hypotheses and insights into processes. We conclude with some reminders about the 'inconvenient truths' that keep the sea-level scientist honest. [ABSTRACT FROM AUTHOR]

Abstract Greenland Ice Sheet (GrIS) covers an area of 1.7 million km2. It has been an important source of climate information and the air temperature history of Greenland is well known. However, the thermal history and temperature conditions of the Greenland bedrock are poorly known. There are only few records on the temperature of the proglacial bedrock and no records on bedrock temperature underneath the ice sheet. The Greenland Analogue Project (GAP) recently investigated hydrological, hydrogeological and geochemical processes in Kangerlussuaq, West Greenland. Because permafrost has a major hydrological impact in Arctic regions, the cryogenic structure of the bedrock was an important research topic. From previous studies it was already known that Kangerlussuaq is located within the zone of continuous permafrost. Temperature profiling in a new research borehole, extending horizontally 30 m underneath the ice sheet, revealed that permafrost is 350 m deep at the ice margin. This result raised the question how far the permafrost extends under the ice sheet? In order to investigate the thermal properties, we made a series of electromagnetic (EM) soundings at the ice margin area – on proglacial area and on the ice sheet – and detected, that subglacial permafrost extends at least 2 km from the ice margin to inland. We also observed a patchy unfrozen sediment layer between the ice and the frozen bedrock. Possible existence of subglacial sediments and their role in ice dynamics has been debated in many recent papers. Our successful campaign shows that geophysics can be used for bedrock investigations through thick ice, which is known to be challenging for electromagnetic methods. Our results provide the first direct evidence supporting the proposed Holocene ice re-advance over frozen ground, and contribute to the discussion on the rapid climate changes in past, to the future of the ice sheet under warming climate and hydrogeology at the ice margin. Highlights • This paper is related to an international research project, the Greenland Analogue Project. • Electromagnetic method was able to discriminate unfrozen and frozen ground. • The first published description of cryogenic structure under continental ice sheet. • Ice re-advance over permafrost evidencing significant Holocene retreat to the east. • A literature review of the Holocene deglaciation of West Greenland. [ABSTRACT FROM AUTHOR]

The study of human‐driven processes is useful to gain a better understanding of the long‐term evolution of land degradation, soil erosion, and geomorphology as well as resource availability for human settlement. The objective of this paper is to identify the long‐term results of human impact on the vulnerable dryland ecosystems in Northwest Argentina, specifically to analyze the consequences of the spread and consolidation of the agricultural way of life on the landscape. To reach this objective, a multiproxy interdisciplinary geoarchaeological study was conducted to link an evolutionary geomorphological model with the soil development and degradation, peopling, and land use change during the Upper Holocene and integrate distinct areas of the Tafí Valley region, which is the most studied area, other neighbouring valleys, and the Puna. The analyses identified positive human‐driven impacts that led to a general degradation of the landscape during the agricultural Prehispanic Period, dated between ca. 2000 and 500 bp. This degradation is manifested by accelerated morphogenesis, mainly fine‐grained accumulated sediments, thick deposits, and the presence of human debris interbedded with the natural sediments. The success of the productive agricultural systems that expanded during the Formative Period led to a gradual increase in the demographic density, resulting in extensive environmental degradation due to overexploitation of the drylands of Northwest Argentina, in some cases increased by adverse climatic changes. [ABSTRACT FROM AUTHOR]