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<jats:p> We present a multiproxy analysis of a sediment core from Freshwater Pond, Barbuda, one of just a few inland paleoenvironmental records from the Lesser Antilles. Our results shed light on the relative contributions of climate variability and Pre- and Post-Columbian human activities to vegetation and fire dynamics on Barbuda. The presence of macroscopic charcoal and pollen of ethnobotanically-useful and disturbance-indicator plant taxa in the sediment record suggests that Pre-Columbian subsistence activities occurred within a few kilometers of the pond between ~150 BCE and ~1250 CE. Our record extends anthropogenic fires back into the early Ceramic (500 BCE–1500 CE) and possibly late Archaic Ages (3000–500 BCE) adding evidence to the timing of arrival of the island’s earliest inhabitants. The history of island-wide biomass burning inferred from microscopic charcoal fragments showed heightened fire activity between ~540 and ~1610 CE followed by a period of quiescence that reflected the transition from Pre- to Post-Columbian land-use practices associated with European colonization of the region. The British established a permanent settlement on Barbuda in the 1660s, but given Barbuda’s unsuitability for large-scale agriculture, timber harvesting, small-scale farming, and livestock rearing, activities that left no detectable charcoal footprints likely dominated post-colonial land use. The lack of any clear correspondence between the reconstructed histories of fire and effective moisture at Freshwater Pond supports the idea that Late-Holocene fire activity on Barbuda was driven primarily by human activity. </jats:p>

<jats:p> Multi-archive studies of climate events and archive-specific response times require synchronous time scales. Aligning common variations in the cosmogenic radionuclide production rate via curve fitting methods provides a tool for the continuous synchronization of natural environmental archives down to decadal precision. Based on this approach, we synchronize <jats:sup>10</jats:sup>Be records from Western Gotland Basin (WGB, Baltic Sea) and Lake Kälksjön (KKJ, central Sweden) sediments to the <jats:sup>14</jats:sup>C production time series from the IntCal20 calibration curve during the Mid-Holocene period ~6400 to 5200 a BP. Before the synchronization, we assess and reduce non-production variability in the <jats:sup>10</jats:sup>Be records by using <jats:sup>10</jats:sup>Be/<jats:sup>9</jats:sup>Be ratios and removing common variability with the TOC record from KKJ sediments based on regression analysis. The synchronizations to the IntCal20 <jats:sup>14</jats:sup>C production time scale suggest decadal to multi-decadal refinements of the WGB and KKJ chronologies. These refinements reduce the previously centennial chronological uncertainties of both archives to about ± 20 (WGB) and ±40 (KKJ) years. Combining proxy time series from the synchronized archives enables us to interpret a period of ventilation in the deep central Baltic Sea basins from ~6250 to 6000 a BP as possibly caused by inter-annual cooling reducing vertical water temperature gradients allowing deep water formation during exceptionally cold winters. </jats:p>

<jats:p> Agropastoralism has prevailed in Inner Asia since the Bronze Age. It is an optimal subsistence strategy of inhabitants for adaptation to arid marginal environment. However, previous studies paid little attention to different development trajectories of this mixed economy within similar habitat. The Turpan and Hami Basins, located in eastern Tianshan Mountains of Xinjiang, are two typical desert oases with extremely dry climate, providing us with an appropriate region to investigate the issue. In present study, radiocarbon dates ( n = 154) of eight typical sites in these two basins were reviewed and used to reconstruct the prehistoric chronology sequence prior to Han Dynasty (2200 cal BP). Then the data of botanical and faunal remains and stable isotope analyses ( n = 159) of human diets from these sites were also reviewed for reliably revealing the subsistence economy pattern. Combining the time scale with multiple biological proxies, results show that, from the Bronze Age to early Iron Age, inhabitant subsistence in the Turpan Basin was dominated by livestock herding and supplemented by low-investment cereal crop cultivation, while the agriculture in Turpan Basin has developed significantly by the later period of Subeixi Culture. In contrast, agriculture-based economy was continuously developed in the Hami oases. Although the climate is very dry in both basins, temperature in warm seasons is much higher in the Turpan Basin. Besides thermal condition, size, range and convenient availability of highland pasture located at the southern flank of the Tianshan Mountains, are main driving factors leading to differentiated development trajectories of agropastoralism. Apart from that, cultural factors like economy, culture and technology communication along with population migration also impact local subsistence economy pattern. </jats:p>

<jats:p> The analysis of the ASTC1 sediment core from the south Aegean Sea region offers critical insights into the complex interplay of geological and climatic factors over the Holocene period. The data reveals fluctuating climatic conditions during the last 8.7 ka as seen through the elemental concentrations obtained by XRF core scanning combined with a qualitative mineral analysis within a robust chronological framework. Short-term fluctuations in both Ti/Al and Zr/Si ratios suggest brief oscillations of increased aridity which partially coincide with the Holocene “Rapid Climate Change” events (RCCs). Among them, the most pronounced in our record are those centered between 8.5–8 ka, 3–2.5 ka (Greek Dark Ages), and 0.6–0.3 ka (Little Ice Age). The arid and humid events identified in the sediment record align with major archaeological periods in Greece, suggesting a potential influence of climatic conditions on the development and decline of civilizations in the region. Moreover, a general arid trend as of 6 ka toward the present was evidenced in our record and aligns with other high-resolution climatic data from the Northern Hemisphere, suggesting climatic teleconnections. Spectral analysis of the ASTC1 record reveals cyclical climate patterns with periodicities of approximately 2500, 1200, and 550 years, which coincide with the Bond and Hallstatt cycles. The phase relation of these cycles in our record, the Greenland ice record, and the North Atlantic Drift ice indices show that colder conditions in the higher latitudes are expressed as events of enhanced aridity in our record and generally in the lower latitudinal regions. </jats:p>

<jats:p> In high northern latitudes, the Middle to Late-Holocene was a time of orbitally-induced atmospheric cooling. This led to increased sea-ice production in the Arctic Ocean and its export southward, a decrease in sea surface temperatures (SST), and glacier advances at least since 5–4 ka BP. However, the response of the ocean-climate system to decreasing insolation was not uniform. Our research shows that the sea-ice cover in the northwestern Barents Sea experienced a late response to Neoglacial cooling. We analyzed dinoflagellate cyst assemblages from a sediment core from Storfjordrenna, south of Svalbard. We found that the area experienced ice-free conditions throughout most of the Mid- and Late-Holocene. It was only after 2.3 ka BP that the study site became covered with winter drift ice and primary productivity decreased subsequently. Other regional data support the decrease in SST, the expansion of the sea-ice cover, and the deterioration of the environmental conditions around that time. Our findings indicate that the sea-ice cover in the northwestern Barents Sea required a significant amount of time to respond to the general cooling trend in the region. These results have important implications for present-day environmental changes. Even if the current warming trend is revoked in the future, the observed sea-ice loss in the Barents Sea may be incredibly challenging to reverse. </jats:p>

<jats:p> There is growing concern about the response of contemporary ecosystems to increasing and novel anthropogenic pressures and environmental conditions. Palaeoecology is crucial to understanding how ecosystems have responded to past environmental changes and can inform management of contemporary ecosystems and contribute to forecasts of ecosystem responses to change. However, palaeoecological data are subject to uncertainties that arise from environmental processes, field and laboratory methods, and data processing, and that affects inferences drawn from them. Understanding how different sources of uncertainty affect the analyses of proxy records remains limited, and records are often interpreted solely qualitatively. We present a virtual ecology approach for assessing how uncertainties inherent in empirical proxy data influence statistical analyses and the inferences drawn from them. In the virtual ecology approach, both the data and the observational process are recreated in simulation to assess sampling and analytical methods. We demonstrate results from a new model for simulating core-type samples of pseudoproxies comparable to empirical proxy data but not subject to the same sources of proxy and chronological uncertainties. These ‘error-free’ pseudoproxies generated under known driving conditions have uncertainties (e.g. core mixing, sub-sampling, and proxy quantification) systematically introduced to them to assess how individual and combined sources of uncertainty influence analytical methods. Results indicate that inferences drawn from statistical analysis, such as the stability of a system, or the rate of ecological turnover, can change substantially between the ‘error-free’ pseudoproxies, and degraded and sub-sampled data. We show how our approach can advance understanding of uncertainties in palaeoecological data and how it can help shape research questions by quantifying of their influence on proxy data. </jats:p>

<jats:p> Although rare, temporally and taxonomically highly-resolved palaeoecological studies with high chronological precision are essential to perform detailed comparisons with precisely dated independent evidence such as archaeological findings, historical events, or palaeoclimatic data. Using a new highly-resolved and chronologically precise sedimentary record from Lago di Mezzano (central Italy), we reconstruct decadal-scale vegetation, species diversity, and fire dynamics, aiming to better understand the linkages between climate, land use, fire, and plant communities from the Neolithic to the Copper Age (c. 5100–3100 cal. BC). Closed, mixed beech-oak forests, including evergreen Quercus ilex, dominated the landscape around Lago di Mezzano during the Neolithic and were disturbed by repeated opening phases, with important implications for lake biogeochemistry and mixing regimes. This was in conjunction with increasing fire activity to promote agro-pastoral practices, as inferred from increasing charcoal, Cerealia type, Triticum type, Hordeum type, Plantago lanceolata type, and Urtica pollen. Fires, on their turn, augmented species diversity (richness and evenness). The comparison of the Mediterranean record from Lago di Mezzano with available continuous and high-precision submediterranean and cool-temperate palynological sequences suggests comparable land use pulses across Southern and Central European regions, most likely in connection with climate change. The outcomes of this study are not only of palaeoecological and archaeological interest; they may also help to improve projections of ecosystem dynamics under future global change. </jats:p>

<jats:p> NW Iberia is dominated by Atlantic climate areas that favour pollen preservation, useful for palaeoecological studies. However, the region also includes Mediterranean sectors in which preservation of such palaeoenvironmental evidence is more difficult. To overcome these constraints, archaeological plant macroremains can be used to help characterize flora and vegetation dynamics at a local and regional level. To fill the gap in knowledge in an understudied Mediterranean region, a large archaeobotanical study was conducted at the river Sabor valley, NE Portugal. With 13 archaeological sites sampled for charcoal, fruits and seeds, it allowed the study of vegetation throughout the Holocene, starting in the Mesolithic up to Modern times, with some chronological gaps. Tree taxa dominates the older period and an expansion of shrubby taxa since Bronze age was observed. Diversification of plants used during the Iron Age and Roman period suggests an intensification of resources exploitation and deforestation. These trends seem to be related with changes in human settlements and productive strategies. During Prehistory, agricultural fields were established in flat and wide areas, and, during Iron Age, fortified granaries were used to store large amounts of grains, particularly free-threshing wheat. Drastic changes in settlement during Roman times and the establishment of small farms producing wine and/or olive oil were testified by the occurrence of Olea and Vitis in both anthracological and carpological datasets. Data from more recent periods is scarce. Results highlight that the combination of several proxies and integration of archaeological evidence helps to understand ecological dynamics in areas without pollen data and contributes to the characterization of heterogeneous areas under diverse climatic conditions and with a variety of social trends. </jats:p>

<jats:p> Numerous oral histories and substantial ethnographic evidence illustrate how plant species, communities, and even landscapes were extensively managed and cared for by ancestral communities in the Pacific Northwest. Camas ( Camassia spp.) is one such cultural keystone plant, common from the Pacific Ocean to the Rocky Mountains, with numerous records describing its role as a staple food for many Northwest peoples. Supporting deep time archeological evidence for such management or stewardship practices, however, has remained elusive. In this paper we analyze archived collections of archeological camas bulbs from 11 sites across the Willamette Valley, Oregon to demonstrate people began preparing camas within earth ovens by approximately 8000 calendar years before present and deliberately harvesting sexually mature camas plants circa 3500 calendar years before present. We compare these findings with climatological, palynological, and fire history reconstructions to discuss stewardship strategies for camas and associated plant communities through time at the population, community, and landscape levels. These findings confirm and expand upon Indigenous knowledges as well as offer time-tested methods for cultural keystone conservationists seeking to revitalize traditional plant stewardship practices throughout this region and beyond. This “camas case study” also offers another example of a human-plant symbiotic relationship, expanding our knowledge of plant food pathways, processes, and mutualisms. </jats:p>