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<jats:p> Both modern and historical data show that lake systems are undergoing profound changes because of human impacts from local to global scales. Research on this topic shows that human pressure on water systems can take various forms and is highly variable in time and space. This article presents the results of Ostracoda fauna research as an indicator of anthropogenic changes covering the time span from 7000 BP to the Mediaeval Period. The palaeoecological information (abundance and habitat preferences of Ostracoda assemblages) obtained in studies of fossil Ostracoda fauna communities amplified by palynological and archaeological data allowed to answer the following questions: (1) to what extent the impact of successive archaeological settlement cultures caused ecological changes in the lake catchment areas without directly affecting the lakes themselves, and when anthropogenic pressure caused transformations in the functioning of lake ecosystems and (2) whether the neolithization, as the first clearly legible stage of anthropopression, had a decisive influence on the functioning of lake ecosystems. Results of Ostracoda fauna studies have been compared with archaeological data available in the literature and multiproxy paleoenvironmental data previously published in a study of lake sediments in the Chełm Hills in South-Eastern Poland. Presented results of study of Ostracoda in lake sediments as a bioindicators of anthropogenic impact suggest that the pressure of prehistoric settlement in older phases (up to the early Middle Ages) was most clearly reflected in the landscape, while the functioning of lake ecosystems was disturbed only by the periodic increase in lake trophic status. A substantial change resulting from the analysis of the subfossil Ostracoda in all the studied lake ecosystems occurred in the phase of settlement related to the Early Middle Ages, which was reflected in the permanently changed species composition of the fauna. </jats:p>

<jats:p> Climatic changes and sea level variations have had a significant impact on the mangroves along the Brazilian coast during the Holocene. The present study focused on understanding the specific factors that have determined the establishment and expansion of mangroves in a subtropical estuary of southern Brazil (Babitonga Bay, State of Santa Catarina-SC), as well as their response to climate change and sea level variations during the late-Holocene. In this study, we carried out sedimentary analysis, palynology, and radiocarbon dating (C-14) to paleoenvironmental reconstruction of the last 1500 cal. year BP. Three facies associations were identified, indicating a progradational succession where a tidal flat was developed at the margin of the estuary. During the first phase, between at least 1440 and ±1286 cal. year BP, the area was characterized by a subtidal environment. The presence of Laguncularia pollen grains since ± 1390 cal. year BP indicated favorable conditions for mangrove establishment in proximity to the study site. Subsequently, around ± 1286 cal. year BP, the tidal flat developed, reaching the present-day shoreline, facilitated by the relative sea level drop. Avicennia trees were established on the tidal flat since ± 1273 cal. year BP, and the establishment of Rhizophora trees occurred in the most recent decades. This mangrove succession developed in Babitonga Bay following a temperature gradient, associated with low-temperature tolerance, and likely its establishment is associated with a temperature increase during the late-Holocene, that caused a migration of the southern limit of the mangrove in the subtropical zone to higher latitudes. Furthermore, the relatively slow expansion of mangroves upstream of Babitonga Bay also may have been controlled by the suitable salinity and substrate conditions, which were favored by the relative sea-level fall during the late-Holocene. </jats:p>

<jats:p> By the time of the Mid-Holocene Ulmus pollen decline (UD) ca. 5100 <jats:sup>14</jats:sup>C bp (ca. 5900 cal. BP), the Neolithic was becoming well established in Britain and Ireland. The importance of cereal cultivation as part of the initial neolithization process in the British Isles is uncertain, as archaeological sites of the first Neolithic remain elusive. Palaeoecologists have recorded cereal-type pollen grains in peat deposits that pre-date the UD significantly, but as some wild grasses can produce pollen that closely resembles cereal pollen grains, these early pollen records are not trusted as evidence of cereal cultivation. Some of these wild grass taxa grow in coastal wetland environments, making cereal-type pollen from such locations particularly open to question. This study uses fine-resolution palynology through a sequence of coastal hydroseral deposits that contain no evidence of human activity, to look for the presence of wild grass pollen of cereal size and morphology. Our results show that while such grains are not recorded at 1 cm resolution, at contiguous 2 mm resolution sampling sporadic occurrences of large grass pollen of possible cereal-type, resembling Hordeum, were detected. Morphology suggests that these cereal-type grains are of wild grass origin, almost certainly Glyceria, but their presence suggests that high-resolution analyses of coastal zone sediments will often discover cereal-type grains. Great care must be taken in identifying cereal-type pollen in coastal palaeo-wetland sediments, and rigorous identification protocols should be applied. Where grains could still be of cultivated cereal-type, the presence of other disturbance indicators is an important factor in inferring their origin. </jats:p>

<jats:p> Recent paleoclimatic research has revealed that volcanic events around 536–540 AD caused severe, short-term global cooling. For this same period, archeological research from various regions evidences significant cultural transformation. However, there is still a lack of understanding of how human societies responded and adapted to extreme climate variability and new circumstances. This study focuses on the effects of the 536/540 AD volcanic event in four Scandinavian regions by exploring the shift in demographic and land use intensity before, during, and after this abrupt climate cooling. To achieve this, we performed climate simulations with and without volcanic eruptions using a dynamically downscaled climate model (iLOVECLIM) at a high resolution (0.25° or ~25 km). We integrated the findings with a comprehensive collection of radiocarbon dates from excavated archeological sites across various Scandinavian regions. Our Earth System Model simulates pronounced cooling (maximum ensemble mean −1.1°C), an abrupt reduction in precipitation, and a particularly acute drop in growing degree days (GDD0) after the volcanic event, which can be used to infer likely impacts on agricultural productivity. When compared to the archeological record, we see considerable regional diversity in the societal response to this sudden environmental event. As a result, this study provides a more comprehensive insight into the demographic chronology of Scandinavia and a deeper understanding of the land-use practices its societies depended on during the 536/540 AD event. Our results suggest that this abrupt climate anomaly amplified a social change already in progress. </jats:p>

<jats:p> We conducted multi-proxy analyses in two subalpine lakes, Lake Gropile, in the Rodna Mountains and Lake Vinderelu in the Maramureș Mountains, the Eastern Carpathians, Romania, to investigate the effect of different land-use practices on landscape composition, diversity and slope erosion. In the case of Lake Gropile, results evidenced a more extended tree and shrub cover and high fire activity between 6400 and 2800 cal yr BP, accompanied by reduced soil erosion, which appeared more strongly regulated by climatic conditions. Anthropogenic impact became evident 2800 years ago, when landscape openness, pasturing, and disturbance of soil cover increased and intensified over the last four centuries. In the case of Lake Vinderelu, intensified burning was followed by grazing around 1200–1100 cal yr BP and continued throughout the last millennium. Results also highlight the site-specific effects of land-use on vegetation composition and landscape diversity. For Lake Vinderelu, a combined effect of local burning and grazing in removing shrub cover appear to be the main drivers of changes in landscape diversity and structure. At Lake Gropile, fire was more connected to shrub cover changes while grazing to herbaceous cover diversity. Moderate to low grazing appeared to benefit both subalpine ecosystems, creating rich grassland-shrub mosaic communities, while overgrazing reduced landscape diversity and exacerbated erosion. Our findings document the millennial-scale legacy of land-use practices on the subalpine landscapes in this region. We propose that these semi-natural ecosystems hold important ecological and cultural value, and recommend their maintenance through controlled, low intensity pasturing and/or burning. </jats:p>

<jats:p> Through unfamiliar and at times marginal environments, successful colonisation of the Pacific Islands relied upon the introduction of domesticated flora and fauna as well as widespread burning to reduce forests and lowland vegetation for agricultural production. These transformations led to the extinction of avifauna, the reduction of forests, and extensive slope erosion and sedimentation into valleys and along shorelines. To date, most attention has been paid to human-induced changes to the terrestrial landscape. In this paper we present the archaeomalacological results from the deeply stratified coastal Kawela Mound, one of the oldest habitation sites in the Hawaiian Islands, with occupation beginning during the 12th century AD. We describe how anthropogenic change of the terrestrial landscape caused sediment run-off, increased shoreline turbidity, and progradation of the adjacent shoreline altering marine habitats, which is recorded in the diversity, size, and habitat preference of food shellfish harvested over nearly eight centuries. The construction of ancient stone-walled fishponds along the littoral shore provided an artificial rocky habitat for shellfish otherwise uncommon along the sandy coast. Consequently, AMS dated layers containing these shellfish provide an indirect avenue for determining the chronology of stone-walled fishponds, the construction of which was directed under the aegis of elites and thus one of the hallmarks of increasing social complexity during the last two centuries before Contact in the late 18th century. </jats:p>

<jats:p> An array of lake sediment proxies including paleobotanic, geochemical, and historical records has been used to determine former environments of Bugbee Pond, a small, mesotrophic pond in northeastern Minnesota. Much research has been produced on the history of climate and vegetation change of the region, yet we have little information on the impact of human settlement. This well-dated, high resolution, multi-proxy record is important for its length and concentration on the historic period. The lake itself became established by ~7000 years ago. Pollen evidence suggests a transition between the regional Prairie Period to the Great Lakes mixed conifer – hardwood forest was established in the region at this time. XRF data suggest dry basin accumulation early in the record after ~7000 cal yr BP, but lake levels substantially increased by ~5600 cal yr BP, during a regionwide climatic transition to more humid conditions. Birch and boreal conifers increased after about 3800 cal yr BP; further increases in boreal conifers occurred by ~2000 cal yr BP. Anthropogenic vegetation changes during the Historic period, beginning in the late 19th century, is well represented by forest clearance of white pine ( Pinus strobus), followed by increases in early successional species and an increased sediment accumulation rate due to land clearance. Establishment of farming communities locally are shown by occurrence of corn ( Zea mays) and oat ( Avena sativa) pollen, and pasturing and grazing are documented by Rumex, Fabaceae and Poaceae pollen, as well as coprophilous fungi, such as Sordaria. The increase and subsequent decline in Pb and S concentrations in the uppermost sediments are mirrored by historically documented, nearby industrial activities. </jats:p>

<jats:p> Detailed palaeogeographical studies of the accumulative fan in the Serteyka River valley in W Russia and underlying biogenic deposits were carried out. The base of a representative core of biogenic sediments in the distal zone is dated to 1291 BC, while its top to 1631 AD. In this paper, palynological, plant macrofossils, Chironomide and Cladocera, geochemical, geochronological and sedimentological analysis were performed. Four phases of biogenic deposition were distinguished by pollen and geochemical analyses. Two of them coincide with the climatic fluctuation during Medieval Climate Anomaly and Little Ice Age. During the formation of the fan, overbank deposits were accumulated also, indicating numerous and intense floods, which are in line with the trend observed for other sites in this region. The accumulative fan is formed by lower, middle and upper deluvia and agricultural diamicton in its top. All units have specific sedimentological and geochemical features as well as low admixture of plant macrofossils. The beginning of the formation of this relief form dates back to the second half of the 17<jats:sup>th</jats:sup> century AD, and the end of the accumulation falls on the second half of the 18<jats:sup>th</jats:sup> century AD. Our work suggests that natural conditions had an impact on the formation and development of studied accumulative fan, however, the decisive factor causing the intensification of the slope processes were related with deforestation resulted from strong human impact, which was marked in palynological and macrofossils analyses (e.g. increase in the contribution of plants macrofossils related to agriculture). </jats:p>

<jats:p> Alluvial-lacustrine deposits are important carriers for studying paleo-hydrological information and the evolution of paleo-environments. In this study, a total of 6 optically stimulated luminescence (OSL) samples from 2 profiles in the lower and middle reaches of the Hutubi River in the North Tianshan Mountains were dated, and a comprehensive analysis was conducted by integrating sedimentary structures, grain sizes, and magnetic susceptibility characteristics to explore the sedimentary environment patterns and regional evolution processes during the Mid to late Holocene. The results revealed the following findings: (1) The OSL signal of quartz samples indicates the predominance of fast components, allowing reliable dating of regional fluvial sediments using the appropriate condition-tested coarse-grained quartz single-aliquot regenerative dose (SAR) protocol within the 90–125 μm range. (2) Analysis of sedimentary structures, grain sizes, and magnetic susceptibility characteristics reveals lithofacies of heterotopic synchronous or homotopic asynchronous in exposed profiles, with predominantly poorly sorted fine and very fine sand. Magnetic susceptibility is primarily controlled by the content of magnetic minerals in the coarse particles, while also being influenced by the combined effects of provenance input and depositional environment, indicating a complex regional sedimentary environment influenced by variable hydrodynamic conditions driven by fluvial processes. (3) Based on OSL dating results and the analysis of various environmental proxy indicators, it is determined that the climatic environment in the Middle and Late-Holocene in the downstream areas of the northern piedmonts of the Tianshan Mountains demonstrates a fluctuating pattern of wet and dry alternations. The sedimentary environment shifted from a stable state in the Mid-Holocene to an unstable state in the Late-Holocene. The intermittent appearance of wet records may be associated with increased river activity caused presumably by the release of high-altitude ice due to rising temperatures and warming conditions. </jats:p>