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Paleolimnology is a rapidly expanding field within the natural sciences. To date, many scientific papers have been published focusing on studies of remains from single sediment cores in specific lakes, or a few cores from the same water body. However, few previous publications have provided a comprehensive comparative analysis of taphocenosis (and maternal community) changes in different water bodies from a large geographical region during whole Holocene using multivariate statistical methods. We conducted a joined statistical analysis of data obtained as a result of the cladoceran analysis of the sediment samples from six cores taken along the North-South transect from the Kola Peninsula to the Karelian Region (North-West Russia). Our aim was to identify, based on quantitative statistical methods, general whole-Holocene patterns in cladoceran taphocenosis changes. All taphocenoses in all cores from six lakes can be classified into six clusters based on their species composition. Our unexpected conclusion is that different taphocoenoses are formed by the same set of species, but their proportions vary significantly. This suggests that the same species may play different functional roles in different maternal communities. During whole Holocene, we observed a single taphocenosis cluster in the Holocene core from Lake Antyukh-Lambina, and four taphocenosis clusters in the Lake Medvedevskoe, with an intermediate number of clusters in the lakes between them. Furthermore, it can be asserted that the potential for cluster changes in the core is greater for the more southern studied water bodies (0–3 clusters for northern lakes vs. 4 clusters for southern lakes). Based on our data, we hypothesize that the diversity of cladoceran associations during the Holocene was lower in Arctic/Subarctic lakes, possibly due to their formation by ubiquitous species. Our study suggests that at least some Arctic lake ecosystems have remained unchanged since deglaciation times. Further studies are necessary to determine if this is a general rule. [ABSTRACT FROM AUTHOR]

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

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

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

The main drivers of Europe's climate during the Holocene result from the coupling and interplay of external and internal radiative processes with the shifting patterns of many dynamic components (e.g. glaciers, ocean currents, wind fields, vegetation cover). Those driving forces were expressed across a range of geographical scales, from local to global, in a diverse set of records forming a patchwork of evidence as to the fundamental pacing effect of climate on past ecosystems. Various sedimentary deposits resulting from those complex forcing contexts bear climatic signatures that it is not always easy to disentangle especially with respect to local factors. The present paper focuses on a coastal archaeological site on the Medoc peninsula (the Lède du Gurp site in south-western France) that records Holocene palaeoenvironmental changes, decoded here century after century and integrated with ongoing events on a pan-North-Atlantic scale. Based on updated geoarchaeological approaches, thanks to new applications of proxies, especially X-ray fluorescence (XRF) core scanning methods for this article, continuous sedimentary records have been analysed in order to reconstruct a regional framework for past ecosystem events, including events potentially related to human activity. Our work identifies signals on various scales in the record under study, with both long- and short-term trends and local and global imprints, but all closely bound up with proximal North Atlantic Ocean dynamics. It highlights how western European environments (and so populations) were dependent upon the linearity of climate evolution at the key Northgrippian/Meghalayan transition. [ABSTRACT FROM AUTHOR]

An overview of the Late Pleistocene and Holocene stratigraphy of the southeastern White Sea region is presented in the paper, based upon the analysis of published data, new results, and correlation between marine and terrestrial archives. The Pleistocene stratigraphic record in the southeastern White Sea region begins with Mikulino Horizon, which comprises the whole MIS 5 and is composed of marine sediments – sands, sandy clays and clays – with Boreal, Arctic–Boreal and Lusitanean–Boreal microfauna and mollusc fauna, dated back at 161–77 ka. The Podporozhie Horizon in the southeastern White Sea region comprises the MIS 4 (71–57 ka) complex of marine mostly near-shore sediments. The glaciation during MIS 4 was localized, on one hand, within the Kola Peninsula. On the other hand, the glacier probably overlapped the Kanin Peninsula and the Mezen Bay, however the Gorlo Strait was not blocked and the northward river outflow was preserved. The Leningrad Horizon had been formed also in the marine sedimentation pattern during the MIS 3 (57–29 ka). However, the lack of data in the region allows us to make only the comparative analysis. The Ostashkov Horizon (MIS 2, 29–11.7 ka) is composed of the deposits of glacial paragenetic series: tills, glaciofluvial, glaciomarine, and glaciolacustrine deposits, but also comprises the deglaciation (Late Glacial) sedimentary complex including marginal tills. The Holocene stratigraphic record is subdivided into three stages – 11.7–9.5, 9.5–3.5 and 3.5–0 ka BP, and do not match with new formal stratigraphic subdivision of the Holocene series. [ABSTRACT FROM AUTHOR]