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This paper presents the first results of palynological research from the Spila nad Procjepom cave, situated in the Mljet National Park, Croatia. The palynological data obtained, enables a partial insight into the local vegetation cover, temporal changes in the vegetation during the accumulation of studied deposits (at ca. 3500 cal years BP), and post-depositional processes that influenced the palynomorph assemblage. Results of palynofacies analysis indicate changes from fluvial (channel deposits), through palustrine to terrestrial environments. Although the interpretation of changes in plant cover, due to the lack of statistical significance, should be taken with caution, preserved pollen types confirm the dominance of the Mediterranean evergreen forest vegetation on Mljet island. Moreover, a high proportion of non-arboreal pollen (NAP) indicates some level of forest degradation, ranging from Mediterranean open forest to degraded maquis. Abundant charcoal additionaly confirms that the cave was inhabited by humans. [ABSTRACT FROM AUTHOR]

This paper describes an approach assuming that already in the sea, based on the express analysis of visually similar cores of Arctic Holocene sediments and their comparison with dated and studied in detail cores of the regional sediments, it is possible to select a material that is promising for sequence stratigraphic correlation and paleoreconstructions. The range of lithological, colorimetric (CIE L*, CIE a*, and CIE b*), geophysical (magnetic susceptibility), and geochemical (Fe/Rb, Mn/Rb, and Ti/Rb) parameters is analyzed. The most informative characteristics include the CIE b* color coordinate, magnetic susceptibility, and Fe/Rb. [ABSTRACT FROM AUTHOR]

Impact craters are formed by collisions of cosmic bodies moving with hypervelocity. The formation of these features is not restricted to the distant geological past; new structures are constantly being created and at least 13 confirmed impact craters and crater fields have formed during the Holocene alone. This short review paper: (1) introduces the basics of the impact cratering process to physical geographers and Quaternary geologists; (2) provides a short description of representative examples of such features (Morasko, Kaali, Kamil, Ilumetsa); and (3) discusses the similarities and differences among very small craters, and contrasts these with larger impact structures. This manuscript may be useful to researchers planning to test whether a small Quaternary depression in the ground may be of impact origin. [ABSTRACT FROM AUTHOR]

Recent climate and environment over the Tibetan Plateau (TP) have undergone significant changes, dominated by variations in the Westerlies and the Indian summer monsoon. However, long‐term shifts in atmospheric circulation during the transitional seasons are still lacking. Here we investigate the modern distribution of Tsuga pollen over the central‐western TP and confirm it as an indicator of variable atmospheric circulation in spring. By combining our Tsuga record from Taro Co with existing records in the Tsuga pollen source area, we suggest that a potential particle transport pathway from the southern slope of the Himalayas to the interior of the plateau appeared in the spring of the late Holocene. Our results show that the springtime atmospheric circulation over the southwestern TP during the early and late Holocene is closely related to the substantial remnants of ice sheets at northern high latitudes and the frequency of El Niño events, respectively. Plain Language Summary: The spring climate over the Tibetan Plateau (TP) is undergoing significant changes that yield profound impacts on environmental changes such as variations in vegetation phenology and alpine treeline. Knowledge of long‐term variations in atmospheric circulation during spring can improve the understanding of current climatic and environmental change and the projection of future variability. In this paper, we use an exotic pollen grain, which can be transported long distances in the air, as an indicator to trace the variability of spring atmospheric circulation over the TP. The results indicate that the spring meridional atmospheric circulation from the southern slope of the TP to its interior has been enhanced in the last four thousand years, which is mainly influenced by the frequency of El Niño events. Key Points: Spring atmospheric circulation change over the southwestern Tibetan Plateau (TP) during Holocene is reconstructedMeridional atmospheric circulation in spring over the southwestern TP is strengthened in the late HoloceneHigh‐(low‐) latitude forcing mainly influence the variations in spring atmospheric circulation during the early (late) Holocene [ABSTRACT FROM AUTHOR]

Despite the wealth of Late Pleistocene archaeology that exists across southern Africa's open landscape, it is routinely neglected in favour of rock shelter (re)excavation, biasing interpretation of human–environment interaction. This is compounded by the scarcity of open-air studies that use geoarchaeological methods to investigate the history and processes involved in their formation. The open-air archaeology of the Doring River Valley is an example of this, despite nearly a decade of dedicated study and publication. Consequently, there remains a limited and untested understanding of the valley's formation history. This paper rectifies this by providing a sedimentary context for the surface archaeology exposed across one of the Doring River Valley's artefact-baring localities, Uitspankraal 7 (UPK7). Characterisation, particle size, mineralogical, morphometric, and geophysical analysis of UPK7′s sand mantle resulted in the identification of four artefact-bearing sedimentary units, the aeolian and pedogenic processes involved in their formation, and their proposed order of deposition. This provides a stratigraphic, taphonomic, and environmental context against which chronometric dating and an analysis of the taphonomic, spatio-temporal, and technological composition of UPK7′s surface archaeology can be compared. This work is the first vital step towards understanding the depositional and behavioural history of a landscape, irrespective of context type. [ABSTRACT FROM AUTHOR]

This paper develops a composite absolute paleointensity record for Holocene paleomagnetic secular variation (PSV) from central North America. Twelve full‐vector (inclination, declination, paleointensity) PSV records were assessed in order to build the composite record. Nine of the paleointensity records come from sediment paleomagnetic studies and are considered relative in intensity. Three of the paleointensity records come from absolute paleointensity measurements of archeological materials and lava flows. This paper develops a new method to normalize the sediment relative paleointensity records to the absolute intensity records. The final composite paleointensity record describes intensity variability over a region of Central North America delineated by 35°–48.6°N and 240.4–291.4°E (∼14° × 50°). This composite record shows a distinctive long‐duration (∼104 year) oscillation and a series of millennial‐scale intensity oscillations that are consistent over our study region. Plain Language Summary: This study develops a composite record of geomagnetic field intensity for the central North America for the last 8,000 years. This record is important for considering the total geomagnetic field variability I this region and its dynamo source(s). Key Points: We develop a new composite absolute paleointensity record for Holocene Central North AmericaWe develop a new renormalization technique to combine absolute paleointensity records and sediment relative paleointensity recordsThe final composite absolute paleointensity record has a distinctive long‐term trend and millennial‐scale variability [ABSTRACT FROM AUTHOR]

Clues of climate change on the Alashan Plateau since the last glacial period (40 ka) are important for revealing the mechanism of desertification of middle-latitude deserts in the Northern Hemisphere (NH). Studies are still rare for the understanding of the specific relationship of climate changes between the Alashan Plateau and the global. Based on a systematic and comparative analysis of the existing research in China and the international academic community, this paper reviews the environmental evolution history of the Alashan Plateau since the last glacial period from the records of paleo-environment and geomorphological characteristics in different deserts of the plateau (e.g., Badanjilin, Tenggeli, and Wulanbuhe). From about 40 ka to the end of the last glacial maximum, the climate on the plateau was wetter than it is today, and to the end of the Pleistocene, the climate was generally dry and the aeolian activities were enhanced. However, the climate was arid during the whole last glacial period in the Wulanbuhe Desert, evidently different from the overall pattern of the plateau. The Tenggeli Desert was characterized by an arid climate in the early Holocene. The most controversial events for the Alashan Plateau are the drought events in the middle Holocene in the Badanjilin Desert. The role and impact of the westerlies and the East Asian Summer Monsoon (EASM) systems on the climate change of the desert and even the whole plateau is a vexed question that brings different views in different periods. There is still a lack of definite evidence representing the events of global environmental change that occurred on the plateau during the discussed period. The distinctive morphology of dune mountains and the distribution of sand dunes are mutually indicative of the direction and energy of wind systems on the plateau. It is suggested that appropriate wind energy is the significant key to the desertification in these middle-latitude deserts on the plateau. From a global-scale review of climate change, the desertification of the modern-scale sandy desert landscapes on the Alashan Plateau is generally related to the global glacial period and the cold and dry climate during the past 40 ka. [ABSTRACT FROM AUTHOR]

The North American Monsoon (NAM) is a critical component of the hydrologic cycle in southwestern North America. However, our understanding of the long‐term evolution of this monsoon system is incomplete due to a paucity of long‐term paleoclimatic records from the core and periphery of the NAM domain. C. Routson et al. (2022, https://doi.org/10.1029/2022gl099772) leverage a new compilation of Holocene proxy records to generate a new composite index of NAM evolution over the Holocene. They identify a relationship between NAM strength and the latitudinal temperature gradient over the Holocene. The authors suggest that shifts in the strength of the westerlies altered NAM convection via ventilation, a process whereby the large‐scale circulation imports low moist entropy air into the monsoon domain. These results highlight the importance of paleoclimatic records, especially from past "warm" intervals, for generating new insights about the evolution of regional monsoons. Plain Language Summary: The North American Monsoon is a circulation that brings summer rain to regions of the US southwest and western Mexico. Despite the fact that this circulation provides a majority of the precipitation in many parts of the arid southwest, we do not fully understand the factors that govern long‐term changes in this monsoon. A new paper by C. Routson et al. (2022, https://doi.org/10.1029/2022gl099772) uses proxy indicators of past summer rainfall, stretching from Central America to Arizona, to reconstruct changes in the monsoon over the geologic epoch known as the Holocene, or the last 11,000 years of Earth history. The results of this study suggest that Holocene changes in the temperature difference between the equator to pole, known as the "latitudinal temperature gradient," exerted an important influence over monsoon strength in the southwest. This has implications for the future of the summer monsoon, especially as the high latitudes of the northern hemisphere are expected to warm in the future. Key Point: The strength North American Monsoon tracks changes in the position of the midlatitude westerlies over the Holocene [ABSTRACT FROM AUTHOR]

Climate variability has probably affected the frequency and distribution of debris flows and snow avalanches throughout the Holocene. In this paper, we reconstruct the Holocene history of debris flows and snow avalanches by investigating outcrops in colluvial fans surrounding lake Anestølsvatnet in western Norway and sediment cores penetrating the lake-floor deposits. We made a detailed map of the surface deposits around the lake. The formation of a large end moraine that dams the lake was radiocarbon dated to 10,200-10,800 cal. yr BP, and correlates to the Erdalen event, a Preboreal glacial oscillation. There are colluvial fans and debris-flow paths and snow-avalanche paths eroded on the steep slopes around the lake. On the western slopes, the fans are dominated by snow avalanches, and on the eastern slopes by debris-flow activity. Three of the lake cores were taken distal to the largest avalanche fan on the western slope, Storeskreda ('Storeskreda' means 'the big landslide'). Clasts > 2 mm in the lake sediments are interpreted as traces of snow avalanches and sorted sand layers as being derived from debris flows. Loss-on-ignition and magnetic susceptibility measurements document an increased silt content in the lake sediments after c. 6000 cal. yr BP, probably due to the reappearance of local glaciers in the area. Our combined data from the onshore outcrops/pits and lake sediments shows almost continuous snowavalanche activity and debris-flow activity throughout the last 10,000 years. However, there may have been an increase in the snow-avalanche activity over the last 5000 years. [ABSTRACT FROM AUTHOR]

The following paper addresses the study of those knapping processes occurred during the middle Holocene in Laguna de los Pampas (Central Pampean Dunefields, Buenos Aires), carried out through tecnomorphologic and technological (chaînes opératoires) studies of the lithic artifacts recovered in the surface of the Sector 2. The results obtained points to the employ of a wide diversity of raw materials, which sources are located at least 170 km away from the site, and among which stands the orthoquartzites and cherts from Tandilia. For these two rocks, as well as for the silicified dolomite, a direct acquisition is proposed. The production of blanks was mainly made by the unipolar and centripetal débitage. The presence of dull edges, reactivation flakes and exhausted cores, as well as the employment of the bipolar reduction, suggest an optimization in the exploitation of rocks. [ABSTRACT FROM AUTHOR]

The paper surveys the Quaternary (MN17-Q4) fossil record of Cricetinae in the Czech Republic and Slovakia with particular attention to the current glacial cycle (Q4: Vistulian-Holocene) and immediate history of extant taxa. Vast majority of records were reexamined using standardized techniques of morphometric analysis (in total 625 molars of Cricetus, 805 molars of small hamsters). Cricetus cricetus, recorded in 130 Q4 fossil communities, exhibits almost continuous appearance since the beginning of Vistulian, possibly with considerable range regressions during LGM and middle Holocene. It was recorded also in 27 Early Pleistocene (MN17-Q2) and 6 Middle Pleistocene (Q3) assemblages, with a small-sized form (Cricetus cricetus nanus) in MN17-Q1 stage and a mosaic of Q2-Q3 records exhibiting mostly excessively large size (C. c. runtonensis), similarly as the Vistulian items which are clearly larger than those of the post-LGM and early Holocene age. The appearance of hamster in fossil record shows a mosaic character suggesting temporal spatial and abundance fluctuations: in most sites it absents and in general, it appears as a rather rare sub-recedent element (in Q4 communities with overall dominance of mere 0.55% and this is valid also for its appearance in Early and Middle Pleistocene assemblages). Small hamsters arranged here in the genus Cricetulus (incl. Allocricetus) represent a constant element of the Early and Middle Pleistocene assemblages (43 sites in the Czech Republic and Slovakia). The items of Q4 record (21 communities) clearly differ from the Early to Middle Pleistocene form Cricetulus bursae by a consistently smaller size corresponding to extant species Cricetulus migratorius. The gap is quite distinct conforming even to the possible extinction of C. bursae during the Eemian interglacial followed by early Vistulian expansion of the extant species from its Asiatic range suggested by molecular phylogeography. We examined a question of possible appearance of Phodopus among the Q4 record of small hamsters, yet in our material, we did not succeed to confirm it. [ABSTRACT FROM AUTHOR]

This paper reviews the distribution of Pinus koraiensis in the south of the Russian Far East in the past based on palynological and chronological data. The aim is to determine the chronological timing of the spatial migration of Pinus koraiensis and to correlate it with climate fluctuations explaining the changes of the geographical range of Pinus koraiensis in the south of the Russian Far East during the Marine Isotope Stages MIS 5 (127 000--71 000 BP), MIS 3 (57 000 BP -- 28 000 cal BP), MIS 2 (28 000--11 700 cal BP), and MIS 1 (11 700 cal BP -- to present). The consideration of the obtained pollen fossil data suggests that the range of Pinus koraiensis was in the south of the Russian Far East during MIS 5, as it was proved based on significant pollen grain percentage in the sediments of this age. Pinus koraiensis was widespread along with Pinus densiflora, Quercus, Ulmus, Juglans, Carpinus, and Phellodendron. During MIS 3, Pinus koraiensis was a component of birch-fir and birch-broadleaved forests. In MIS 2, Pinus koraiensis disappeared from the vegetation of this region. In the early Holocene, Pinus koraiensis expanded its range northward and again appeared in the vegetation of the south of the Russian Far East. Soon enough, it became one of the leading components in spruce-fir forests with Quercus and Ulmus. The increase in its proportion in the vegetation in the Holocene coincided mostly with the periods of warming climate from 11 700 to 11 500 cal BP, from 10 100 to 9300 cal BP, from 8800 to 5300 cal BP, from 4700 to 3500 cal BP, and from 2600 to 1800 cal BP. In the present case, the most diverse vegetation with Pinus koraiensis was typical of the Holocene optimum of the south of the Russian Far East from 8800 to 5300 cal BP. [ABSTRACT FROM AUTHOR]

The Bohai Sea is a semi-enclosed shallow shelf sea that has undergone a unique sediment source-to-sink process in the past. Despite this, our knowledge about the sediment budget, existence of depocenters and the factors controlling depocenter formation during the Holocene remains limited. This paper aims to address these gaps by estimating the Holocene marine deposit thickness and sediment budget in the Bohai Sea using high-resolution subbottom profiles. The results reveal that the mean thickness of Holocene marine deposits is approximately 7.8 m and a maximum thickness of 28 m was found in Jinzhou Bay. The Highstand System Tracts (HST) have a mean thickness of approximately 5.4 m and a maximum thickness of 25 m observed in the Jinzhou Bay. On the other hand, the Transgressive System Tracts (TST) have a mean thickness of approximately 2.5 m and a maximum thickness of 7 m in the north of the Laizhou Bay. The total accumulation in the Bohai Sea is estimated to be ∼713.97 × 109 tons, consisting of 489.28 × 109 tons from the HST and 224.69 × 109 tons from the TST. Three deposit centers were identified and estimated to be approximately 299 × 109 tons, accounting for approximately 42 % of the total Bohai Sea sediments. The development of Holocene marine deposit centers was mainly influenced by the Tanlu Fault zone and water circulations. Based on preliminary estimates, it is suggested that roughly half of the sediments dispersed from the estuaries are preserved on the Bohai Sea shelf since the maximum flooding (∼7000 cal yr BP). This research provides valuable insights for the post-glacial sedimentary and geomorphic evolution of the Bohai Sea. • Holocene marine accumulation in the Bohai Sea is estimated to be ∼713.97 × 109 tons. • Accumulation in HST is of ∼489.28 × 109 tons and that in TST is of ∼224.69 × 109 tons. • Three depocenters were identified and account for ∼42 % of the total accumulation. • Roughly half of the sediments were preserved on the shelf over the past 7000 years. [ABSTRACT FROM AUTHOR]

The paper presents a brief account of the temporal changes found in proportions of the mammal components in the diets of several species of predators (owls and carnivores) collected from various sites in Slovakia and originating in various periods (Late Pleistocene–Recent). The material collected from the Šarkanica Cave (Muráňska planina Mts.) contained bones in three layers, dated using the radiocarbon analysis (14 C) to 18,000–21,000 years BP (18–21 Ka), showing relatively small differences in composition of the fossil diet of Bubo scandiacus with predominance of Lasiopodomys gregalis (73.3%) and Chio- nomys nivalis (6.9%). A similar type of material from the Nový 3 Cave (Belianske Tatry Mts.), dated to the period of 30 Ka, contained more numerous remnants of Lemmus cf. lemmus and Sorex tundrensis. Undated samples from the Nový 1 Cave and from the Šarkania diera Cave (Súľovské skaly Mts.), which differ in their higher abundance of Dicrostonyx cf. gulielmi, are probably dated from the colder period of the last glacial maximum. Three samples from caves in the Veľká Fatra Mts. dated from the Late Pleisto- cene (Upper Dryas) originated from carnivores, with differences in relative proportions of predominant prey species: Chionomys nivalis (80.0%) and Lasiopodomys gregalis (14.3%), while remains of Cricetus cricetus (0.6%) also appear there. Two examples of differences in the diet composition of Strix aluco in the Veľká Fatra Mts. are present in samples dated to the Holocene period: natural development of forest fauna in the environs of Dolný Harmanec and anthropogenic influence in the form of three deforestation periods in the Tlstá massif near Blatnica (both Veľká Fatra Mts.). A sample set of the diet of Tyto alba dated >500 years BP from a church in Žilina is compared with a recent sample set of this owl diet from the Turčianska kotlina Basin and from the Danubian Lowland (Tekovské Lužany). The main difference lies in the greater proportion of the murid rodents and the relatively lower abundance of Microtus arvalis in the sample from the 16th century. Similar results were found comparing samples of Tyto alba diet, taken from a cave near Hatiny (Slovenský kras Mts.) and expected to be 100 years old, with more recent samples from the Košická kotlina Basin. The collection from the Hatiny Cave differs from the recent material in the presence of Sicista trizona and Alexandromys oeconomus. The recent samples of the diet of Bubo bubo taken from the Horné Považie Basin differ from the samples dated back more than 70 years ago by a high proportion of the genus Apodemus and a predominant incidence of frogs, while the old samples come from the period of the communist influence of the agricultural production causing serious environmental changes in the countryside (1950s) and as a result, a greater volume of large prey species, Rattus norvegicus, Arvicola amphibius, Lepus europaeus, and Erinaceus roumanicus. Since 1990, the availability of large prey for Bubo bubo has decreased due to the decline of livestock farming and a con- sequent successional overgrowing of pasture land by trees. [ABSTRACT FROM AUTHOR]

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]

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]

This paper analyzes the origins of two tombolos (one recent and another fossil/submerged) on the southwestern coast of Prvić Island, which is located in the Kvarner area in the northeastern part of the Adriatic Sea. A recent tombolo on Cape Pipa was formed by the erosion of Quaternary deposits and Palaeogene siliciclastic rocks. The submerged tombolo is much bigger, clearly visible on the sea bed toward the southwest. The conditions for forming a submerged and recent tombolo have occurred during a slow rise and then stagnation of sea level of the Adriatic Sea in the Holocene. The sea flooded the fossil tombolo probably in the final part of a period of rapid sea-level rise at the beginning of the Holocene when a large proportion of the Quaternary sediments were eroded. Waves from the northwest (tramuntana) and southeast (jugo) refract and diffract around the tombolo. The nourishment of the beach body happens permanently on both sides of the cape. Accumulated sediments are protected by resistant rocky blocks of breccia on the peak of Cape Pipa, acting as a natural tombolo. Due to the fact that wave directions are perpendicular to the beach coastline, they do not generate longshore currents that would erode sediment in beach bodies around Cape Pipa. Therefore, the recent tombolo is probably stable in the present climatic and oceanographic conditions in the Kvarner area. [ABSTRACT FROM AUTHOR]

In this paper we present the magnetic dating results of five independent lava flows belonging to the Ceboruco volcanic field in Jalisco, western Mexico, using the SHADIF14K geomagnetic field prediction model. Five lava flows corresponding to well-documented eruptive events were studied. The ages of these flows have already been established by radiometric methods (C14). In two sites the archaeomagnetic ages coincide with C14 ages previously reported. In one site the archaeomagnetic age is considerably different from the radiocarbon age, possibly due to a discrepancy between one or both of the ages and the actual age of emplacement. For the two remaining lava flows, the paleomagnetic directions were found to be scattered and thus no characteristic remanence was determined. These sites probably underwent some rotation or a later displacement that was unnoticed during the sampling. [ABSTRACT FROM AUTHOR]

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]

Numerous karst dolines have been formed along the Croatian coast and many have been submerged during the Late Glacial and Holocene sea level rise. The coastal area of Cres Island in the Northern Adriatic is a typical example of this geomorphological setting, where transitional forms from subaerial to submerged dolines are present. Once dolines are formed they can accumulate soil, water and sediments due to their morphology. Sediments are an especially valuable source of environmental data. This paper presents the results of the study of foraminiferal assemblages and sediment geochemistry, supplemented with grain-size and mineralogical data, from the marine ponds developed in the karst dolines on Cres Island. Obtained data is correlated with the sediment core record from submerged dolines in the present-day embayments along the coastal zone of Cres Island. In total, 3 sediment cores were collected in the marine ponds Marinska, Arcij and Podbrajde, while 2 longer sediment cores have been extracted from the Jaz and Sonte embayments. The Marinska, Arcij and Podbrajde marine ponds have distinct geochemical and mineralogical sediment compositions, with monospecific foraminiferal assemblages and generally differ from each other. The common characteristics are their high N and P concentrations and the algal origin of organic matter. Agglutinated foraminiferal taxa (Haplophragmoides canariensis and Trochammina inflata), typical for intertidal environments, are abundant in the brackish-water Marinska pond, while stress-tolerant species Ammonia tepida has been identified in the Arcij marine pond. Environmental conditions in the Podbrajde marine pond did not facilitate the development of a rich foraminiferal fauna. Results from the present-day marine ponds enabled recognition of similar environments in the sediment cores collected in the Jaz and Sonte embayments that were progressively inundated during the Holocene sea level rise. A palaeo-marine pond existed in the Sonte embayment until 6610 cal BP, when the sea flooded the investigated area. A marine pond in the Jaz embayment was formed at 711 cal BP. Low-diversity foraminiferal assemblages in these palaeo-ponds are similar to those recognized in the present-day Arcij marine pond on Cres Island. However, differences in the geochemical composition of palaeo-marine ponds, in comparison to the present-day ponds, exist. They might be attributed to climate variability over time and variations in the geological setting of each environment. High Mo concentrations and abundant organic matter content are the main sediment characteristics of the recognized palaeo-marine ponds in the Jaz and Sonte embayments. [ABSTRACT FROM AUTHOR]

This paper illustrates a detailed geomorphological map (scale 1:50,000) of the marine and transitional terraces (glacio-lacustrine to marine) and raised shorelines linked to Holocene glacio-eustasy and neo-tectonics in the northern area of the Brunswick Penìnsula (Chilean region of the Strait of Magellan). The mapped area is located in Tierra del Fuego between the Segunda Angostura and Seno Otway. This map is the result of geomorphological field survey data integrated with the interpretation of aerial photographs and remote sensing imagery. The survey has allowed the mapping of a sequence of terraces and raised shorelines to be completed. The sequence mainly consists of four orders of marine and glacio-lacustrine terraced deposits, with elevations ranging from 25 to 1 m above mean sea level. The map also presents other landforms and deposits, with their formation linked to littoral, fluvial, glacial and aeolian processes. [ABSTRACT FROM AUTHOR]

Although there is rich evidence for human occupation of Paros’ coastline, there is a dearth of data with regards to the evolution of the island's seaboard palaeoenvironments. In this paper, we use sedimentological and palaeontological proxies of late Holocene coastal deposits from lagoonal environment to reconstruct the evolution of coastal landscapes in Paroikia Bay (Paros Island, Greece). A semi-enclosed lagoon existed in the northeastern part of Paroikia from at least 2915–2551 BC, which was gradually infilled after around 780–436 BC. Although it was not possible to chronologically constrain the timing of the infill, it is most likely relatively young, indicating anthropogenic effects. A correlation of our chronostratigraphic data with archaeological remains and tidal notches in the study area suggests that the subsidence observed on Paros Island is linked to long-term subsidence in combination with vertical seismic displacements. [ABSTRACT FROM AUTHOR]

Rate of global eustatic sea-level rise during the Holocene Epoch has been identified as the principle cause of observed changes or inferred evolution of nontectonic coastal systems in mid- to low-latitude areas. The rate of rise is now three times faster than it was for the past several thousand years and similar to values associated with the middle Holocene marine transgression. This acceleration can be attributed to human-caused global warming. In this investigation, the effects of accelerating sea-level rise on coastal sedimentary environments of the SE Saline Everglades were quantified. The results reveal historic changes to coastal habitat, sedimentation, and stratigraphy that are transgressive. These changes initiated during the early 20th century and are attributed to accelerating sea-level rise. As this acceleration and the resulting geologic record is a suspected consequence of human-induced global warming, the paper concludes with a discussion of the relevance of these observations, in tandem with others, to the current debate over the utility and use of the proposed Anthropocene. [ABSTRACT FROM AUTHOR]

An editorial is presented which discusses the strides made by conservation science and practice in ecological sustainability and social justice and refers several papers submitted by authors on the subject. He expresses that traditional and local knowledge had contributed in building social-ecological systems resilience like in Great Bear Rainforest, British Columbia, wherein local Indigenous governments along with other network of institutions are participating to maintain it.

Marine oxygen isotope stage 5a (MIS 5a), MIS 3a, and Holocene were highlighted periods in paleoclimate studies. Many scientists have published a great number of studies in this regard, but they paid more attention to qualitative research, and there was often a lack of quantitative data. In this paper, based on chronological evidence from a paleolake in arid China, MIS 5a, MIS 3a, and Holocene lake area, the precipitation of the drainage area and the runoff of the inflowing rivers of the lake were reconstructed with ArcGIS spatial analysis software and the improved water and energy balance model which was calibrated by modern meteorological and hydrological data in the Shiyang River drainage basin. The results showed that the paleolake areas were 1824, 1124, and 628 km for MIS 5a, MIS 3a, and Holocene; meanwhile, the paleoprecipitation and runoff were 293.992-297.433, 271.105-274.294, and 249.431-252.373 mm and 29.103 × 10-29.496 × 10, 18.810 × 10-18.959 × 10, and 10.637 × 10-10.777 × 10 mm, respectively. The quantitative data can help us not only strengthen the understanding of paleoclimatic characteristics but also recognize the complexity and diversity of the climate system. [ABSTRACT FROM AUTHOR]

The paper presents the chronology of the Holocene evolution of the Baltic Sea based on the optically stimulated luminescence (OSL) and radiocarbon dating methods applied to a core taken from the Arkona Basin. The dating results were supplemented by grain size and geochemical analysis. The obtained results of OSL and radiocarbon dating enabled the construction of an age-depth model and confirmed the continuous sedimentation since 9900 cal yrs BP. One of the most interesting findings of this study is a clear relationship between the rate of sedimentation and fluctuations in the energy of depositional environment. The analyzed sediment core revealed two sections of different accumulation rates. The bottom section was deposited until 2700 cal yrs BP when the Ancylus Lake and the Littorina Sea were present, characterized by the accumulation rate estimated at around 0.46 mm year-1 and the dynamic sedimentation environment confirmed by grain size parameters. The accumulation rate at the top section deposited during the Post-Littorina Sea stage was estimated at around 1 mm year-1. This stage, characterized by more stable deposition and lower-energy environment conditions, was confirmed by small grain size, symmetric skewness and increasing content of organic matter. [ABSTRACT FROM AUTHOR]

This paper considers regularities governing the formation of automorphic tundra soils on glacial loamy deposits containing relict organic matter mainly represented by very fine plant detritus. Drainage, microtopography, and cryoturbation activity are the major controls of the development of these soils. With an increase in drainage, the following pedogenetic trend is observed on the surface of yedoma (Ice Сomplex) areas: gleyzem-cryozem-cryometamorphic soil. The climate change in the Holocene induced quick transformation of topography and general landscape situation and promoted formation and development of cryogenic soil complexes in the considered territory. Upon the low intensity of pedogenesis, the features and properties of previous soil formation stages are often preserved in the soil profiles; these are: gleyzation, peat accumulation, and cryoturbation. [ABSTRACT FROM AUTHOR]

This paper documents the history of vegetation assemblage in Honghe Wetland (NE China) during the last 6200 years. Vegetation changes were reconstructed based on high-resolution plant macrofossil analysis of sedimentary sequence obtained from Honghe National Nature Reserve located in Sanjiang Plain, in conjunction with Accelerator Mass Spectrometry (AMS) 14 C radiocarbon data. Results indicate that plant macrofossil composition of Honghe wetland ecosystem are dynamic and have undergone several significant changes. Around 2500 cal yr BP, plant composition transited from Equisetum fluviatile community to Carex lasiocarpa - Drepanocladus aduncus community, and then following by Drepanocladus aduncus community at 460 cal yr BP. Another major vegetation changes occurred at 220 cal yr BP, transitioning to Carex sp. community. By comparison between the plant macrofossil assemblages and the climate changes during the last 6200 cal yr BP, we suggest that ASM (Asian summer monsoon) is the main driving force for the vegetation succession before the impacts of human activities. Since some restoration programs have been undertaken at Honghe wetland, thus our results can provide valuable baseline data for assessment of the practicability and suitability of the former restoration plan and the further designing of conservation management and restoration targets. Since the vegetation composition of Honghe wetland is pronouncedly sensitive to water level, it can be inferred that wetland ecosystem can be restored to near-natural condition through the effective management and restoration by controlling the water source of the wetland. [ABSTRACT FROM AUTHOR]

Aim Projections of human impact on the environment and biodiversity patterns are crucial if we are to prevent their destruction. Such projections usually involve the assumption that the same human activities always affect biodiversity in the same way, either in geographically distant areas within the same time-scale or in the same areas in different periods. In this paper, plant and snail fossils from central Europe that cover the last 12,000 years provide evidence against this assumption. Location Central Europe. Methods We examined fossil data on central European plants and snails and extracted time-series of (1) local species richness (alpha diversity) at a scale of approximately 300 m × 300 m and decays of (2) the Jaccard index and (3) Simpson's beta with increasing distance (up to approximately 400 km) through time. Results We show that two vital biodiversity patterns follow neither oxygen-isotope nor borehole temperature proxies, but instead vary between archaeologically known periods, with the most noticeable and irreversible breaks (1) when arable agriculture was introduced into central Europe, (2) when the Roman Empire collapsed, and (3) during the event known as the 12th-century colonization in central Europe. The patterns computed from data across time sometimes contradicted the patterns computed across space. Main conclusions We therefore infer that people can, and sometimes have, contributed to temporal changes in ecological rules that are seemingly general across space. Our findings indicate that the changes in ecological rules are so substantial that efforts to project future biodiversity based on space-for-time substitution might fail, unless we gain knowledge about how these general rules are altered. [ABSTRACT FROM AUTHOR]

South American seasonally dry tropical forests (SDTFs) are critically endangered, with only a small proportion of their original distribution remaining. This paper presents a 12 000 year reconstruction of climate change, fire and vegetation dynamics in the Bolivian Chiquitano SDTF, based upon pollen and charcoal analysis, to examine the resilience of this ecosystem to drought and fire. Our analysis demonstrates a complex relationship between climate, fire and floristic composition over multi-millennial time scales, and reveals that moisture variability is the dominant control upon community turnover in this ecosystem. Maximum drought during the Early Holocene, consistent with regional drought reconstructions, correlates with a period of significant fire activity between 8000 and 7000 cal yr BP which resulted in a decrease in SDTF diversity. As fire activity declined but severe regional droughts persisted through the Middle Holocene, SDTFs, including Anadenanthera and Astronium, became firmly established in the Bolivian lowlands. The trend of decreasing fire activity during the last two millennia promotes the idea among forest ecologists that SDTFs are threatened by fire. Our analysis shows that the Chiquitano seasonally dry biome has been more resilient to Holocene changes in climate and fire regime than previously assumed, but raises questions over whether this resilience will continue in the future under increased temperatures and drought coupled with a higher frequency anthropogenic fire regime. [ABSTRACT FROM AUTHOR]

This paper addresses the surface and Holocene aeolian deposits in the southeastern Mu Us Desert, N. China, systematically analysing the evolution of the geochemical characteristics of aeolian sand-palaeosol sequences and their environmental significance. Our results indicate that the geochemical components of the Holocene aeolian deposits and surface deposits had the similar material sources, sediment transport and deposition processes in the study region, which were dominated by SiO2, Al2O3, and Na2O. In the weathering process of the Jinjie (JJ) profile, the Na, K, and Si presented the slight leaching and migration in general, while the other elements were relatively accumulated. The Holocene aeolian deposits and surface deposits incurred weaker geochemical weathering under cold and dry conditions and were only weakly leached, which implies a relatively arid environment in the Holocene epoch and the modern era. The weathering degree was controlled by the regional temperature and precipitation, and was probably more sensitive to the precipitation changes. In the sedimentary profile, the geochemical parameters and migration of elements demonstrated that there have been several alternating warm-wet and cold-dry intervals in the Mu Us Desert in the Holocene epoch; there were relatively warm and wet conditions prior to 4.6 ka, and it has been cold and dry since then. Six millennial-scale dry events were recorded during the Holocene, which were not only accordant with the history of palaeoclimatic changes in the different latitudes and archives of the Northern Hemisphere, but also correspond to the millennial-scale variation of cosmic radiation and solar activity during that period. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Shaw, C.E., 2016. Late Pleistocene bays and reefs: Ancestors to the modern Caribbean coast, Yucatán Península, México. Low-lying indentations along the modern Caribbean coast of the Yucatán Peninsula host shallow bays with classic crescent-shaped, white-sand beaches. These indentations have previously been explained as products of Holocene dissolution of Pleistocene limestones within a brackish coastal mixing zone. This paper demonstrates that the lows confining the modern bays were formed by sedimentary processes 122,000 ± 2000 YBP, during the late Pleistocene. A 50 km stretch of the Caribbean coast between Tankah and Playa del Carmen, here called the high coast, is characterized by rocky headlands that are underlain by fossilized coral reefs of late Pleistocene age and lows between headlands occupied by modern bays. Study of landforms using aerial photographs together with field examination of late Pleistocene calcarenite exposed in quarries has led to recognition of a series of arcuate Pleistocene beaches with large attached spits that developed during a period of falling sea level that followed the oxygen isotope substage 5e sea-level highstand. Pleistocene beaches and associated triangular spits form a series of cuspate arcs, each precisely aligned with one of the modern bays and each triangular spit aligned with the center of a modern headland. This exact and repeated coincidence of substage 5e bays with modern bays and beaches indicates that low areas occupied by modern bays lie within the lowest portions of late Pleistocene bays that were drained during the Wisconsin glacial and reflooded in their lowest parts during the post-Wisconsin rise of sea level in the Holocene. [ABSTRACT FROM AUTHOR]

The geomorphology of a coastal landscape may reveal an indication of past shoreline configurations. The spatial arrangement of the preserved morphologies may further contain indications on the importance of the different key parameters influencing shoreline evolution over millennial timescales, such as palaeo sea-level position, longshore currents, energy gradients, and sediment supply. This paper presents the results and observations of a surveying and mapping study conducted for the island of Samsø at a scale of 1:75,000. The objective of the work is to support the interpretation of core sample data and to extract information on the factors determining the morpho-sedimentary development of moraine-embedded coastal lagoon systems during the Holocene. The map is based on an airborne LiDAR-derived high-resolution digital terrain model that is combined with spatial information on bathymetry, surface geology and other features from archived geodata and maps. [ABSTRACT FROM PUBLISHER]

Exploration of Pliocene, Pleistocene and Holocene deposits in of the Croatian Northern Adriatic and Southern Dalmatia (coastline) offshore is presented in this paper. It was a way to describe the existing lithostratigraphic units in Croatian Po River sediments and to determine such units in the depositional area of Neretva River. Both systems have been influenced by sea-level fluctuations during the Quaternary, resulting in significantly decreased sea depths and increased subaerial exposure during glacial periods, especially in the Northern Adriatic. In the Croatian part of Po Depression, two new formations were mentioned - Istria (Pliocene) and Ivana (Pleistocene, Holocene). Three new lithostratigraphic members were described within Ivana Formation, namely Anamarija, Katarina and Izabela. Further south, in the Southern Dalmatia shallow offshore, Pliocene, Pleistocene and Holocene deposits were named the new Neretva Channel Formation. This formation was further divided into Neretva Sands (sometimes equivalent for entire formation) and the (Quaternary) Mali Ston Bay Member. No typical Pliocene lithotype has yet been recognised. [ABSTRACT FROM AUTHOR]

The tarsometatarsus, a compound bone from the lower leg in birds, is the most important skeletal element in fossil penguin taxonomy, especially in the case of early members of this group. However, any attempt to go beyond the problem of mere classification obviously requires the better understanding of osteological traits under consideration. This in turn touches on the issue of interplay between bone and concomitant soft-tissue structures, such as muscles, tendons and vessels. This paper focuses on the more holistic comprehension of the tarsometatarsal section of the Eocene penguin foot, based on the analysis of the myology and the vascular system of its modern counterparts. A number of graphical reconstructions are provided with a discussion of the role of the hypotarsus and intermetatarsal foramina. [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]

Climate changes, sea-level variations, volcanism and human activity have influenced the environment of the southwest Pacific Islands during the Holocene. The high-resolution palynological analysis presented here concerns two specific levels (main lithological changes) of a well-dated Holocene core, Tfer06, collected from Emaotfer Swamp, Efate Island (Vanuatu). Our aim is to understand the role of climatic variability and human activities in shaping vegetation during these changes. Between 3790–3600 cal yr BP, the development of vegetation marked by disturbance is a marker of an increase in sustained El Niño events, also observed in many Asian-West Pacific areas. Between 1500–900 cal yr BP, the increase in introduced taxa and in microcharcoal particles is interpreted as human impact. In a forthcoming paper, the ongoing high-resolution palynological analysis of the whole core will be compared and integrated into regional palaeoecological data. [ABSTRACT FROM AUTHOR]

It is widely accepted that climate has a strong impact and exerts important feedbacks on erosional processes and sediment transport mechanisms. However, the extent at which climate influences erosion is still a matter of debate. In this paper we test whether frost-cracking processes and related temperature variations can influence the sediment production and surface erosion in a small catchment situated in the eastern Italian Alps. To this extent, we first present a geomorphic map of the region that we complement with published 10 Be-based denudation rates. We then apply a preexisting heat-flow model in order to analyze the variations of the frost-cracking intensity (FCI) in the study area, which could have controlled the sediment production in the basin. Finally, we compare the model results with the pattern of denudation rates and Quaternary deposits in the geomorphic map. The model results, combined with field observations, mapping, and quantitative geomorphic analyses, reveal that frost-cracking processes have had a primary role in the production of sediment where the intensity of sediment supply has been dictated and limited by the combined effect of temperature variations and conditions of bedrock preservation. These results highlight the importance of a yet poorly understood process for the production of sediment in mountain areas. [ABSTRACT FROM AUTHOR]

A major achievement in research supported by the Kluane Lake Research Station was the recovery, in 2001 - 02, of a suite of cores from the icefields of the central St. Elias Mountains, Yukon, by teams of researchers from Canada, the United States, and Japan. This project led to the development of parallel, long (103-104 year) ice-core records of climate and atmospheric change over an altitudinal range of more than 2 km, from the Eclipse Icefield (3017 m) to the ice-covered plateau of Mt. Logan (5340 m). These efforts built on earlier work recovering single ice cores in this region. Comparison of these records has allowed for variations in climate and atmospheric composition to be linked with changes in the vertical structure and dynamics of the North Pacific atmosphere, providing a unique perspective on these changes over the Holocene. Owing to their privileged location, cores from the St. Elias Icefields also contain a remarkably detailed record of aerosols from various sources around or across the North Pacific. In this paper we review major scientific findings from the study of St. Elias Mountain ice cores, focusing on five main themes: (1) The record of stable water isotopes (δ18O, δD), which has unique characteristics that differ from those of Greenland, other Arctic ice cores, and even among sites in the St. Elias; (2) the snow accumulation history; (3) the record of pollen, biomass burning aerosol, and desert dust deposition; (4) the record of long-range air pollutant deposition (sulphate and lead); and (5) the record of paleo-volcanism. Our discussion draws on studies published since 2000, but based on older ice cores from the St. Elias Mountains obtained in 1980 and 1996. [ABSTRACT FROM AUTHOR]

In the Valley of Sobaco located in Coahuila, Mexico, were found the remains of an aquatic ecosystem with a Holocene malacofauna showing similarities to modern aquatic communities of the internationally famous site of Cuatrociénegas, located in the state of Coahuila and known as the "Mexican Galapagos", as it hosts a large number of endemic species. In addition of ostracods, algae, foraminifera, diatoms and remains of vascular plants, the Sobaco paleo-pools (pozas) also contain the gastropods Juturnia coahuilae, Pyrgulopsis manantiali, Coahuilix hubbsi, Coahuilix cf. landyei and Assiminea cienegensis, which are endemic species of Cuatrociénegas Valley. Additional discoveries include sub-recent lacustrine microbial tufas (microbialites, stromatolites), as well a pool that still contains water hosting bacterial communities similar to those from Cuatrociénegas. In this paper we present the taxonomic description of the mollusks from the Sobaco paleo-lake system and a first reconstruction of the paleoenvironment. A comparison of this paleoecosystem with modern aquatic communities of the Cuatrociénegas Valley is also included. [ABSTRACT FROM AUTHOR]

In recent years, more and more record-breaking extreme weather/climate events have been reported from the Asian monsoon region, which have caused tremendous loss of property and lives. In this paper, we analyzed the Asian summer monsoon (ASM) variability during the Holocene and evaluated future climate extremes in monsoonal China from a paleoclimatic view. We found a significant regime transition to more chaotic fluctuations, with enhanced decadal variability of the ASM since 6.6 ka BP. We suggested the gradual intensification of ENSO was responsible for enhancing the ASM variability since the late mid-Holocene. If the observed relationship of monsoon mean intensity, ENSO and decadal variability of the ASM in the past 11.2 ka continue to exist, enhanced decadal variability of ASM in the future warming world will be expected. As a result, the intensification of daily precipitation extremes, superimposed on enhanced decadal variability of ASM, might make the record-breaking extremes more frequent in the future, increasing the risk of climate-related disasters in China. [ABSTRACT FROM AUTHOR]

In tropical Africa, Late Pleistocene-Holocene climatic fluctuations heavily impacted the continental hydro-systems. The timing and magnitude of 'African Humid Period' hydrological dynamics (AHP; ~14.8 to ~5.5 ka BP) are not yet fully understood due to the extreme variability in African geomorphic patterns and the complex network of past air convergence boundary shifts. The investigation of the functioning of specific hydro-sedimentary basins is needed to improve our knowledge on the AHP spatial and chronological patterns over the continent. In this paper we present a revised Holocene lake level curve of Lake Abhe: an endorheic basin situated in the Afar Depression at the northern extremity of the East African Rift System (EARS). Located at the boundary of the Red Sea and the Indian and Atlantic Oceans' air moisture mass fluxes, the Lake Abhe watershed represents a system sensitive to changes in Northeast African hydro-climate. Based on numerous littoral lacustrine geomorphic features and 53 related radiocarbon ages on stromatolites and nearshore deposits, we have defined the main Holocene lake highstands proposing a detailed paleo-shoreline record. The first rise in water level is dated to ~11.1 ka cal. BP, while the Maximal Holocene Highstand Shoreline (~420 m a.s.l.) was rapidly reached around ~10 ka cal. BP. Evidence of the impact of the 8.2 ka North Atlantic cooling event is recognized with slow lake level regression until ~8.3 ka cal. BP and with an abrupt drop at ~8 ka cal. BP. The resurgence of humid conditions was recorded from ~7.7 ka cal. BP to ~4.6 ka cal. BP. Radiocarbon ages on littoral materials allow us to propose a Holocene subsidence rate of the Abhe basin axial valley. Furthermore, multiphase sill overflow incisions towards the downstream Hanle basin and transient fluvial connectivity with the upstream Ziway-Shala basin, indicate strong geomorphic controls on lake highstand elevations. In summary, Lake Abhe Holocene fluctuations are the result of combined hydro-climatic, tectonic and local geomorphic controls. However, the confrontation with others East African basins allows us to discuss the transport of moisture masses dynamics into the northern EARS during the Holocene. [ABSTRACT FROM AUTHOR]

Coastal morphodynamics and environmental changes have been obviously altered by global warming, sea-level fluctuations, and human activities. Palynological analysis is one of the most important tools for providing information on vegetation, climate, and environmental change, which can be relatively sensitive indicators of human activity during the Holocene. However, Holocene coastal morphodynamics and palynological evidence from the Pearl River Delta and coastal areas has not been sufficiently studied. In this paper, we carry out analyses using detailed grain-size and palynological records of pollen, spores, freshwater algae, and marine dinoflagellate cysts from Borehole QZK13 in the Pearl River Estuary (PRE), southern China. The results show information relating coastal morphodynamics, vegetation evolution, climate changes, and anthropogenic activities during the Holocene based on radiocarbon chronology. In general, the PRE experienced marine transgressive processes; sea-level and the coastline tended to migrate landward between 10,700 and 4250 cal yr BP. Meanwhile, abundant arboreal pollen (mainly Castanopsis , Quercus -evergreen, Oleaceae, and Castanea) and small amounts of non-arboreal pollen (mainly Poaceae, Cyperaceae, and Artemisia) were observed in Borehole QZK13, which suggests that subtropical evergreen broadleaved forests were distributed throughout the PRE and adjacent areas, and relatively warm and moist climatic conditions were present during the early-middle Holocene. After that, there were relatively cool and wet climatic conditions, and marine regressive processes occurred in the PRE during the Late Holocene (ca. 4250–960 cal yr BP) indicated by an abrupt increase in aquatic herbs and Dicranopteris. Moreover, we hypothesize that the Neolithic "cultural fault" in the PRE is likely related to frequent storm surges induced by extreme typhoon events that occurred ca. 3000–2700 yr BP. • Grain size, pollen, spores, freshwater algae and dinoflagellate cysts from the Pearl River Estuary were investigated. • Three major phases shown by palynological results were corresponding to the changes in vegetation and climate. • We hypothesized that the Neolithic "cultural fault" is probably related to the storm surges induced by extreme typhoon events. • Natural vegetation cover has suffered large-scale destruction by ancient humans during the Late Holocene. [ABSTRACT FROM AUTHOR]

Palaeomeanders are characteristic features of meandering river floodplains. Some were abandoned several millennia ago and can be used as evidence for past fluvial patterns. Despite many observations of changes undergone by meandering rivers, little is known about long-term morphological adjustment of meanders. This paper reports on investigations conducted in two reaches located in the middle valley of the Cher River (northwestern Europe, France) to examine the readjustments of lowland meanders during the second half of the Holocene. The aim of our study was to provide new insights into the complex dynamics that control low-energy meandering rivers. LiDAR DEM spatial analyses coupled with geophysical surveys and observations of sediments enabled the identification and dating of thirteen palaeomeanders embedded in coarse sediments (sand and gravel) while the whole floodplain is covered by silty overbank deposits. Sedimentological, geochemical and pollen analyses combined with radiocarbon and OSL dating allowed us to reconstruct the chronology of the cutoff and the filling of palaeochannels. No palaeochannels older than ca 6000 yr cal. BP, and no palaeochannels younger than the eleventh–thirteenth centuries cal. AD were identified. This allowed us to distinguish two periods of meandering processes. (1) Our observations demonstrate the multi-millennia persistence of an active meandering pattern in a context of land use changes (ca 6000 yr cal. BP-eleventh–thirteenth centuries cal. AD). The preserved mobility of the river can be mainly interpreted as the result of the low cohesiveness of the bank material. Too few fine sediments were delivered during the proto-historical and historical periods to help stabilize the river course. (2) Following the eleventh–thirteenth centuries cal. AD, the fluvial system underwent a laterally stable phase. The many medieval and modern hydraulic engineering works reduced the specific stream power and prevented lateral erosion. The drastic decrease in the river's capacity to generate new meanders resulted in the disappearance of floodplain lakes and loss of habitat diversity. [ABSTRACT FROM AUTHOR]