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We use a range of environmental variables to explore the possible drivers influencing the biota, especially the composition of aquatic invertebrates, during the Younger Dryas (YD) and Early Holocene (EH) in different river valley sites: a well-developed meandering river and the confluence zone of headwater streams. Using pollen, macrofossil, cladoceran, and chironomid as well as geochemical and lithological data as proxies for environmental factors (i.e., water depth and temperature), we attempt to show that these different sites display similar hydroclimatic signals (especially floods). The geochemical records in the studied valley are correlated with environmental factors, such as the evolution of the vegetation, the intensification phase of slope processes, and fluvial activities. Cladocerans and chironomids potentially play important roles in the recognition of flood episodes in the study sites, and any shift in their diversity and, especially, the co-occurrence of planktonic, sediment-associated cladocerans with rheophilic chironomids could be valuable indicators of floods and flow episodes. The variable changes in water levels at the sites reconstructed by the cladoceran-based water-depth model were positively associated with changes in lithophilic elements (K, Na, Al, Mg, and Ti), SiO 2(biog + ter) and Fe/Mn, and our estimates of the paleohydraulic parameters for the study sites are generally consistent with changes in the composition of aquatic invertebrates. The recorded YD floods appear to be synchronous, regardless of the size and the different geological and geomorphological settings of each part of the river catchment. Our investigation demonstrates that flood magnitude increases in the downstream direction along the valley. The common increases in the water level at all study sites from the Grabia River valley are significant from 12,400 to 12,200 and from 11,900 to 11,800 cal BP and are comparable with those from elsewhere in Poland and Europe. [ABSTRACT FROM AUTHOR]

Abstract: The developmental history, from the Oldest Dryas to the Late Holocene, of a paleolake and mire located in a river valley in Central Poland was studied using high-resolution records of pollen, macrofossils, Cladocera, sedimentology, and geochemistry from a 14 C dated sediment core. We inferred temperature and water level dynamics using cladocerans and palynological and geochemical methods were employed to investigate natural fluvial activity, particularly for these elements that are difficult to find through sedimentological methods. Our research demonstrates how climate fluctuation in the Late Glacial and Holocene periods influenced the development of a paleolake and mire in a small river valley and shows the importance of long-term research to establish hydroclimatic conditions in biogenic sediments. We propose that water level fluctuations were important in modifying biotic assemblages. The results of our multiproxy analysis clearly suggest that the main driver of changes in aquatic and terrestrial ecosystems, as well as in geomorphological processes in the valley, was climate: reconstructed temperatures generally follow the known trends, showing an increase at the beginning of the Bølling, Allerød, and Holocene and a decrease at the beginning of the Oldest and Younger Dryas. Similarly, periods of water level increase are synchronous with climatic changes. However, the local environmental forces were a significant factors affecting biotic diversity in the studied time span. Fish predation, macrophyte structure, pH, and calcium content partly influence the results of the cladoceran-based water depth reconstruction in particular. Interestingly, the cladoceran-inferred summer temperature reconstruction for Pawłowa appear realistic. Although the temperature trends can be considered reliable, our results indicate the important role of local factors which control the species composition of the subfossil assemblages. [ABSTRACT FROM AUTHOR]

Analyses on 27 sediment cores taken from the bottom of the Szczecin Lagoon allowed environmental reconstruction of the postglacial main stages of basin development, based on detailed sedimentological, geochemical, diatomological and malacological studies of selected key cores. Studies revealed that during the Late Glacial and Holocene this area developed in several stages. In the Late Glacial the whole study area constituted a low alluvial plain. At the turn from Younger Dryas to Holocene the alluvial plain was cut through by the Odra river to a level of 10–11 m below sea level (b.s.l.). Along with the first phases of the Holocene marine transgression at the southern Baltic Sea''s coasts the accumulation of the limnic-swampy deposits began in this lower part of the Odra valley. At ca. 6–6.5 ka BP the transgression proceeded and Littorina Sea waters flooded the area. At that time the Szczecin Lagoon constituted a marine embayment in which series of sands, partly rich in malacofauna, was deposited. The development of the Swina barrier resulted in the isolation of the embayment from the direct inflow of Baltic Sea waters. [Copyright &y& Elsevier]

• Chemistry of sediments of Yinggehai basin E slope is correlated to SL- change. • Statistical PCA analysis confirms the essence of chemical variability of sediments. • Largest differences in lithology occur in deltaic sediments near the Hainan island. • Strong seismic reflectors are associated with high content of shell and gravels. • Lithology & chemistry of sediments allow to distinguish prodelta and delta front. The study was aimed at elucidating relationships between lithological and geochemical characteristics of sediments as indicators of sea level changes during the Late Quaternary on the eastern slope of the Yinggehai-Song Hong basin. The focus was on sediments of the late Pleistocene paleodelta formed on the shelf off the Hainan Island. Examination of two cores revealed a significant lithological and geochemical variability of the sediments, particularly in the lower segments of the delta deposits, associated with the delta front (core LDW) and with the distal part of the prodelta (core ZBW). The upper segment of the deltaic sediments in core LDW most likely represents a delta plain formed under the prevalent trend of increasing sea level. On other hand the upper segment of the deltaic sediments in core ZBW should be regarded as associated with sediments of the proximal part of the prodelta, formed when the delta front was advancing and the sea level was first rising and then stabilised. Attention was paid to the relationship between lithological and geochemical features of the sediments and the seismic profiling records, particularly with respect to the paleodelta sediment series. An attempt was also made to link and correlate the sediment series with sea level changes. [ABSTRACT FROM AUTHOR]

The wooly rhinoceros (Coelodonta antiquitatis) and forest rhinoceros (Stephanorhinus kirchbergensis) were prominent representatives of the Middle and Late Pleistocene glacial and interglacial faunas of Eurasia. Their diet has traditionally been inferred on functional morphology of the dentition and skull. In rare cases, food remains are preserved in the fossas of the teeth or as gut content. New approaches to infer diet include the study of isotopes and mesowear. Here we apply all four methods to infer the diet of these emblematic rhinoceros' species and compare the food actually taken with the food available, as indicated by independent botanical data from the localities where the rhinoceros' fossils were found: Gorzów Wielkopolski (Eemian) and Starunia (Middle Vistulian) as well as analysis of literature data. We also made inferences on the season of death of these individuals. Our results indicate that the woolly rhino in both Europe and Asia (Siberia) was mainly a grazer, although at different times of the year and depending on the region its diet was also supplemented by leaves of shrubs and trees. According to the results of isotope studies, there were important individual variations. The data show a clear seasonal variation in the isotope composition of this rhino's diet. In contrast, Stephanorhinus kirchbergensis was a browser, though its diet included low-growing vegetation. Its habitat consisted of various types of forests, from riparian to deciduous and mixed forests, and open areas. The diet of this species consisted of selected items of vegetation, also including plants growing near both flowing and standing waters. The food remains from the fossae of the teeth indicated flexible browsing, confirming the previous interpretations based on functional morphology and stable isotopes. Long-term data from mesowear and microwear across a wider range of S. kirchbergensis fossils indicate a more mixed diet with a browsing component. The different diets of both of rhinoceros reflect not only the different habitats, but also climate changes that occurred during the Late Pleistocene. [ABSTRACT FROM AUTHOR]