Paleoecological reconstructions provide valuable insights into the impacts of environmental change on key functions of wetland ecosystems. Here, we integrate biological and sedimentological proxies to provide a baseline of vegetation and hydrological change since the Middle Holocene at a riparian marsh, with the goal of informing wetland restoration within a regional biodiversity hotspot in the Great Lakes coastal zone. Four stages of wetland development are identified, reflecting the combined impacts of Lake Erie fluctuations, fluvial processes, regional paleoclimate, and anthropogenic influence. Wetland establishment took place ∼6000 cal yr BP during a Lake Erie high stand, and pollen assemblages indicate that the site was initially a forested wetland. Subsequently, water levels remained elevated as a transition to an emergent marsh with silty, organic-rich sediments took place ∼5300 cal yr BP. Once water levels stabilized in the Late Holocene, a thicket swamp established in sandier sediments, suggesting closer proximity to the meandering channel. The intensification of European settlement from 1850 CE marked a major transition, resulting from disturbances caused by land clearance and hydrological alterations, including higher rates of sediment accretion, novel diatom communities, and increases in herbaceous vegetation. These paleoecological records demonstrate the importance of considering whole-watershed measures in restoration planning, including controls on mineral sediment influxes, maintenance of local water tables, and management of invasive species producing high biomass.

Understanding biotic responses to environmental changes will help identify extinction risks and direct conservation efforts to mitigate negative effects associated with anthropogenic-induced environmental changes. Here we use the Quaternary fossil record of mole salamanders (Ambystoma) from the southwestern United States and northern Mexico to reveal geographic patterns of extirpation since the Pleistocene. Ambystoma are known to have previously inhabited regions of central Texas on the Edwards Plateau; however, they are largely absent from the region today. We used a well-dated fossil record of Ambystoma from Hall’s Cave combined with other fossil sites in the region to deduce why Ambystoma was ultimately extirpated from the Edwards Plateau and to test hypotheses related to temperature-driven body-size changes in line with the temperature–size rule. We propose that Ambystoma was likely extirpated from the region due to changing temperature and precipitation regimes that caused increased mortality and disruptions to breeding and larval development. We found some support for decreased body size in Ambystoma with increased temperature during the late Pleistocene, suggesting that body size may be an important feature to monitor in modern populations of Ambystoma as salamanders become subjected to increasingly hotter temperatures in the coming decades.

The Đurđevac Sands constitute a wide area of small-scale dune relief in the Podravina (NE Croatia), located along the central part of the southern Drava River valley. Even though it has been the subject of earlier investigations, the timing and characteristics of aeolian activity and pedogenesis remain unclear. In this study, field investigations and laboratory methods are combined to gather information on past aeolian systems in the southern part of the Pannonian Basin. The results indicate that weak soil formation during the Bølling-Allerød interstadial stabilized the dunes after the first episode of aeolian activity that took place since ca. 18 ka. The source material for dune building is thought to be fluvial sand from the Drava River, which was blown from exposed terraces. During the Younger Dryas and/or Early Holocene, a new phase of aeolian activity is recorded, with material showing stronger evidence of weathering compared to the underlying aeolian material. Finally, during the Mid and/or Late Holocene, dunes were overbuilt once again with fresh unweathered sand. In general, these new findings obtained from the Đurđevac Sands area correlate rather well with other regions in the Pannonian Basin, in terms of the timing and characteristics of soil formation and aeolian activity.

To assess the time scales and relative importance of temporal decoupling between hillslope erosion and the introduction of sediment to streams in a Yangtze River headwater basin, we used multiple techniques to date sediments in alluvial fans and terraces in a third-order stream valley draining a 30-km2 catchment in SW Sichuan, China. Poorly sorted angular sediments in tributary-junction alluvial fans ranged in age from 11261 BCE to 1844 CE, and predominantly fine-grained overbank sediments in alluvial terraces date to approximately 1700–1950. Ethnographic observations and field mapping of hillslope soil depths indicate that terrace sediments and upper strata of several fans correspond to a period of hillslope erosion associated with the intensification of hillslope swidden agriculture. Contemporary sediment production is dominated by lateral fluvial erosion of valley-bottom landforms rather than by hillslope erosion. The long-term temporal decoupling by valley storage of hillslope erosion from sediment delivery to streams has relevance to contemporary hillslope erosion and sedimentation control efforts in the Yangtze Basin. It also motivates investigating whether valley-filling anthropogenic “legacy sediments” may play a role in decoupling hillslope erosion from sediment production in other Yangtze Basin headwater basins.

Identifying use-related residues from stone artefacts has become increasingly important in determining starchy plant exploitation over time and in different locales. Standard methods for processing residues samples are widely available but there is no clear consensus on suitable methods for attributing unknown starch grains to known plant taxa. We revisit the case study of a flaked stone artefact (K/76/S29B) recovered from Phase 1 (c. 10,000 ka) at Kuk Swamp in Papua New Guinea (PNG). Starch grains from taro (Colocasia esculenta) were identified in the residue extraction, but there were other grains that could not be attributed a plant origin at that time. The new analysis applied robust statistical methods, categorial attributes and expert input. In addition to C. esculenta, kudzu bean (Pueraria montana var. lobata) was identified, representing the earliest use of kudzu bean in the PNG highlands. Importantly, we also determined that starch grains from C. esculenta and Dioscorea esculenta are morphologically indistinguishable. We turned to other attributes of potential contributing plant taxa in determining distinguishing features: habit/growing requirements; the sedimentary context of the archaeological find; and environmental settings. Cultural use of both plants, artefacts and artefact technologies can be critical elements in confident identification outcomes, as exemplified here.

A 13,500-year-old record from Langohr Wetland in the Gallatin Range of southwestern Montana offers new insights into the vegetation and fire history at middle elevations within the Greater Yellowstone Ecosystem. Pollen data suggest that following deglaciation, a tundra–steppe established until warmer and wetter conditions than before could support Picea parkland. The development of an open, predominantly Pinus mixed-conifer forest from ca. 9300–7000 cal yr BP suggests warming summer temperatures led to an increase in forest cover and fire activity; the increase in tree abundance supported infrequent, stand-replacing fires approximately every 600 years. Picea and Pseudotsuga increased their presence at ca. 7000 cal yr BP, and the mixed-conifer forest became denser during the Mid- and Late Holocene, suggesting summers became cooler and wetter. The additional fuel load led to increased fire activity, with stand-replacing fires occurring approximately every 350 years in the Late Holocene. The forest surrounding Langohr Wetland experienced less change in vegetation composition and structure and fewer fire episodes than other low- and high-elevation sites in the Greater Yellowstone Ecosystem. The stability of this forested ecosystem over thousands of years is likely a result of its cool mesic mid-elevation setting, limiting the frequency of intense fire episodes.

Submarine landforms in polar fjords provide essential insights into glacier responses to climate change in the Maritime Antarctic. This work aims to reconstruct the groundline of a palaeo-ice stream throughout the Holocene in Admiralty Bay, King George Island. The landforms were investigated using multi-resolution topobathymetric data based on seismic and multibeam surveys. The inner sector features shallow moraine banks and elongated glacial lineations, in contrast to the deeper moraine banks observed in the middle and outer regions of the fjord. Elongated glacial lineations indicate a north-east to south-west ice flow and a wet-based thermal regime. At ~9000 years bp, the grounding line was at the Admiralty Bay fjord’s mouth. In the middle of the fjord, a prominent morainal bank reveals the palaeoglacier’s grounding line. The grounding line significantly changed position after this stillstand in response to climatic variability (Mid-Holocene, at 4500–2800 years bp) and was conditioned by the deep bathymetry. The continued retreat of the ice in the Holocene possibly led to a division of the palaeo-ice stream into outlets or tidewater glaciers. MB7 and MB9 indicate the position of the grounding line during a major stillstand at the end of the inlets. The bedrock topography and fjord geometry influenced the deglaciation pattern of Dobrowolski Glacier in Martel Inlet, and the moraine banks recorded two final major stillstands. The retreat rates in Martel Inlet have increased due to the loss of anchoring points and rising temperatures after the Neoglacial period. The morainal banks present in the proximal environments at Martel Inlet are smaller, discontinuous and spaced, indicating the retreat behaviour in the last 7 decades.

The hypothesis of Paleolithic rock art in Siberia remains neither proven nor disproven. This research provides key evidence for a later age of the earliest known images in the Minusinsk Depression. A set of geological, geomorphological, and absolute-dating methods was utilized to reconstruct the geological history of the Maydashy rock art site (Minusinsk Depression, Southern Siberia). This research for the first time has allowed us to date the lower chronological boundary of the period when the earliest images known in Southern Siberia as “Minusinsk Style” were created. In the Late Pleistocene, the cliff area of the site was buried under alluvial deposits of the first floodplain terrace of the Yenisei River that formed in the second half of MIS 2. At the beginning of the Holocene, before its optimal onset, Yenisei eroded the terrace and exposed the rock surface to mark the potential lower boundary (< 11 ka) when the Maydashy site images were carved. This approach can be useful in rock art research for dating carvings from open-air sites; it is applicable for the rock art sites of other regions where ravine formation affected their natural context.

The stratigraphic record of the Early Holocene in the Nebraska Sand Hills suggests dry climatic conditions and periods of sustained aeolian activity, which resulted in several well-documented instances of sand dunes blocking river drainages in the western Sand Hills. Here, we present evidence that drainage blockage by migrating sand dunes also occurred in the central Sand Hills, where precipitation is higher and dune morphology differs. The South Fork Dismal River valley contains a sequence of aeolian, alluvial, and lacustrine sediments that record a gradual rise of the local water table following a sand dune blockage of the river valley around 11,000 years ago. After the initial development of a wetland, a lake formed and persisted for at least 2000 years. Increased groundwater discharge due to a warm, moist climate in the region after 6500 years ago likely caused the breaching of the dune dam and eventually resulted in the decline of the local water table. Through a careful examination of the intricate relationships between ground water, surface water, and sand movement in a dune field setting, we discuss the hydrologic system's complex response to climate change. We use diatoms to reconstruct the lacustrine environment and optically stimulated luminescence and radiocarbon dating to provide chronological control, based on a careful evaluation of the strengths and limitations of each method in varied depositional environments.

AMS radiocarbon ages of organic matter from ice wedges and enclosing peat were determined for the polygonal peatland at the Lorino site on the eastern coast of the Chukchi Peninsula. The study’s goal was to fill a knowledge gap about the dynamics of polygonal peatlands with ice wedges and winter climate conditions during the Holocene in this easternmost region of the Russian Arctic. It has been found that peatland accumulated during the Younger Dryas and early Holocene, mostly between 14 and 9.9 cal ka BP, while ice wedges were dated from 7.7 to 6.6 cal ka BP. Since ice wedges have features of syngenetic growth, the discrepancy in the age of ice wedges and enclosing peatland may result from the significant presence of early and pre-Holocene peat. It is assumed that the older polygonal peatland deeply thawed during the Holocene optimum, and subsequently, when the permafrost aggraded, a new generation of ice wedges was formed. The AMS 14C age (18.1 cal ka BP) of the ice wedge exposed below the peat indicates the presence of a Late Pleistocene generation of ice wedges at the study site. Paleotemperature reconstructions based on the stable isotope composition of ice wedges show that the mean January air temperature during the Northgrippian stage of the Holocene varied from –27 to –23°C, and at the end of the Late Pleistocene, from –32 to –26°C.

This project employs a geoarchaeological approach to explore human occupation of the highland wetlands (bofedales) and salt flats of the Dry Puna of northern Chile (>2500m above sea level) during the Holocene. Differences in the archaeological record of each ecosystem are tentatively suggested to relate to settlement patterns and the history of the landscape.

To investigate long-term relationships between climate, vegetation, landscape geochemistry and fires in the boreal forest zone of Western Siberia, a sediment core of 345 cm was collected from Shchuchye Lake (located in south taiga zone of southeast part of West Siberian plain) and investigated by spore-pollen, radiocarbon, LOI and charcoal analyses. Quantitative palaeoclimate was reconstructed based on pollen data. Investigation revealed 13.2 cal ka history of vegetation, climate, landscapes and fires. In the dry climate of Late Glacial, the landscape was treeless. Continuous permafrost existed in the soil. In the middle of the YD cooling 12.4–12.2 cal ka BP, our data showed warming that caused degradation of permafrost in soils and settlement of spruce in moist places. Later, thawing and accumulation of moisture in a local lowering in relief increased and a lake was formed. With the beginning of the Holocene, the climate sharply changed to warmer and wetter. Intensified surface flow caused accumulation of mineral and carbonate fraction in the lake. Dense birch forests spread on drylands. As a result, the leaching regime initiated the formation of podzols in the soil. At about 10.0 cal ka BP, Scots pine (Pinus sylvestris) quickly spread in the area of investigation. Fires became more frequent and more intense during the dry Late Glacial time, sharply decreasing with increased precipitation in the Early Holocene, and again moderately increasing with spread of pine forests in the mid Holocene. With the transition to Late Holocene (after 6.0 cal ka BP), the intensity of regional background fires and number of local fires decreased.

Oral traditions describing details of ancient volcanic eruptions and their effects survive throughout the inhabited world. Many such eruptions, especially those having catastrophic environmental and societal consequences, proved sufficiently memorable to form the basis of enduring oral traditions. Using global databases, we identified 2306 such eruptions from 477 inhabited locations that occurred before the start of the Common Era (CE) and are therefore likely to have been the subject of oral traditions. Of these, we selected 20 events (‘remembered’ Holocene eruptions) for which there are extant oral (-derived) traditions that demonstrate how such traditions can reveal details of past volcanism that often are undetectable by retrodictive geoscientific enquiry. We also selected 20 events (‘forgotten’ Holocene eruptions) about which no oral traditions are known and discuss the possible reasons for this. Such oral traditions, while often challenging for conventionally trained geoscientists to interpret, are valuable yet largely overlooked sources of information about the nature and effects of Holocene volcanism that can usefully complement geoscientific enquiry. In particular, we identified locations where memories of such volcanism appear ‘forgotten’ in the hope that scientists might focus their attention on revealing, identifying, and analyzing local traditions.

The analysis of coprolites provides direct evidence of resources consumed and may be paired with ethnographic data to elucidate the dietary and medicinal use of plants in archaeological communities. This article combines and contrasts the macroscopic analysis and DNA metabarcoding of 10 coprolites from Bonneville Estates Rockshelter, Nevada, USA. While the results from both methods confirm previous understandings of subsistence practices at the site, minimal overlap in identified taxa suggests that each accesses different components of the consumed material. The two methods should therefore be seen as complementary and employed together, where possible.

Systematic investigation of caves and rockshelters in Uruguay is revealing the archaeological importance of these sites and their association with earthen mounds. Multiple periods of human occupation at Tamanduá rockshelter are revealed through stratigraphic analysis, and radiocarbon dates suggest recurrent occupation from the Early Holocene up to the historic period.

Secondary carbonate precipitates on the surface of clasts have rarely been reported from Antarctica. Here, we infer the origin, age and palaeo-environmental significance of the calcite crusts in the Untersee Oasis, East Antarctica. The distribution of calcite crusts, which are up to 1 mm thick, is limited to locations with residual snow patches, and they have some of the highest δ18O (up to +17.4‰ Vienna Standard Mean Ocean Water (VSMOW)) and δ13C (up to +14.6‰ Vienna Pee Dee Belemnite (VPDB)) compositions of any carbonate deposits in terrestrial polar environments. Their δ18O and δ13C values are substantially enriched with respect to the isotopic values expected from equilibrium precipitation from the δ18O and δ13CDIC (DIC = dissolved inorganic carbon) of snow meltwater. The formation of the calcite crusts is ascribed to the evaporation of residual snow meltwater and the low relative humidity and strong winds, favouring a kinetic isotope effect. The 14C age distribution of the calcite crusts (1550 cal yr bp to modern) provides a minimum age for ice retreat and drainage of the palaeo-lake in Aurkjosen Cirque. However, in this polar desert environment in which surface melting is limited, the calcite crusts require sufficient snow accumulation and air temperatures warm enough to generate meltwater, and their age distribution corresponds to the late Holocene warm-wet climate period.

High-resolution sedimentological and geochronological investigations of paleochannel systems in the Ried Central d'Alsace (northeastern France) allow for the reconstruction of the late glacial and Holocene fluvial evolution of this section of the Upper Rhine alluvial plain. During the Oldest Dryas, the landscape featured a dominant braided Rhine system and, to a lesser extent, a braided Fecht system. The shift to the Bølling-Allerød saw a narrowing of the Rhine's active channel belt, the development of a complex channel pattern, and the genesis of the Ill River. The river channel patterns remained unchanged during the Younger Dryas. In the Early Holocene, the Rhine's active belt narrowed further, and the Rhine and Ill Rivers developed braided-anastomosing and anastomosing channel patterns, respectively. Throughout the Holocene, both rivers maintained their channel patterns while migrating east and west across the alluvial plain, respectively. In the late glacial, fluvial dynamics in this section of the Upper Rhine plain were primarily influenced by climate-related environmental and hydrogeomorphological changes. Conversely, during the Holocene, the evolution of the fluvial hydrosystems was driven by a complex interaction of climatic and non-climatic factors, including human activity at the catchment scale, alluvial plain architecture, and local neotectonics.

Accelerator mass spectrometry radiocarbon (AMS 14C) dating was used for determining the age of wedge ice. It has been found that between 11,270 and 6420 cal BP, or the Greenlandian and Northgrippian stages of the Holocene, ice wedges grew syngenetically in sandy deposits with gravel in the Chara River valley. The variations of δ18O values in the ice wedges are about 8‰, from –25.5‰ to –18.8‰. Based on the stable isotope composition of ice wedges, paleotemperature reconstructions revealed that the mean January temperature was as low as –38°C during the coldest periods of the early half of the Holocene and as high as –28°C during the warmer periods.