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In addressing the controversial issues of the Late Pleistocene paleogeography of the Caspian basin, an important role is given to the results of the spore-pollen analysis and based on them reconstructions of climate and vegetation changes in the Northern Caspian region during the development of the Early Khvalynian transgression. In this paper we present the main results of the palynological study of deposits (chocolate clays and the overlying and underlying layers from the Srednyaya Akhtuba section) of maximum stage of the Early Khvalynian transgression; the materials are illustrated by pollen diagram with the data of spore-pollen analysis and the detailed list of palynoflora recovered from the studied Lower Khvalynian sequences, and complemented with photographs of pollen belonging to the principal autochtonous taxa and, for comparison, to some redeposited palynomorphs. Palynological materials indicate subaqual (brackish marine and freshwater) sedimentation of the sediments studied in periglacial landscapes and, for the most part, under very harsh climatic conditions. The performed climate-stratigraphic reconstructions do not contradict the data of absolute dating on the accumulation of the studied deposits during the Late Valdai (Ostashkov) late Glacial period. During this interval in the territory of the study area, plant communities of the glacial climate — tundra-steppe, periglacial forest-steppe, periglacial steppe, periglacial parklands and periglacial forests — were developed. The widespread occurrence in the composition of the periglacial vegetation cover of the studied region of the yernik formations from Betula nana and shrub communities from Betula fruticosa , B. nana , Alnaster fruticosus , Juniperus , etc. testifies to the severe climatic conditions and, possibly, the existence of sporadic permafrost in the cold stages (stadials) of the Ostashkov Late Glacial period. [ABSTRACT FROM AUTHOR]

The Pyrenean Lake Montcortès sediments hold the longest continuous and absolutely varve-dated record of the Mediterranean region, encompassing the last three millennia, from the Late Bronze Age to the present. The reconstruction of vegetation and landscape dynamics during this time period has advanced gradually, following the progress of absolute dating by varve counting, and has been progressively published and updated in a number of papers dealing with specific time intervals at different temporal resolutions. This paper synthesizes all these studies in a single composite paleoecological sequence constrained by a single age-depth varve model. The final resolution of this reconstruction is bidecadal, on average, but some periods have been resolved at quasidecadal (Middle Ages) and subdecadal (Modern Age to present) resolutions. The study is focused on the timing of anthropization and the further development of vegetation under climatic and anthropogenic drivers until the shaping of present landscapes. An additional advantage of Montcortès is that the local history of the Pallars region, where the lake is located, is well documented and can be easily correlated with the paleoecological record. Contrary to former interpretations of general landscape anthropization of the Pyrenees during the Middle Ages, the Montcortès catchment was irreversibly transformed by anthropic activities at the beginning of the Iron Age (ca. 750-650 BCE). From this point, the catchment underwent successive transformations due to varied human uses (fire, grazing, cereal cultivation, weed/ruderal plant expansions, hemp cultivation/retting), which have been related to the different cultural phases and sociopolitical changes documented in the local historical records. The regional forests, dominated by Pinus and Quercus , experienced four main clearance events (RD) during the Iron Age (RD1; ca. 300 BCE), the Roman Period (RD2; ca. 300 CE), the Middle Ages (RD3; ca. 1000 CE) and the Modern Age (RD4; ca. 1800 CE). The detailed trends of the last two deforestation events and their causes could be studied at a decadal resolution, which significantly improved interpretation quality in ecological terms. The potential effects of climatic changes and the eventual interactions with human activities on catchment vegetation and regional forests throughout the record have also been discussed. The Montcortès record has been compared with other records at local (Pyrenees), regional (Iberian Peninsula) and biome (Mediterranean) scales. Locally and regionally, anthropization times and further ecological trends showed significant heterogeneity according to elevation, biogeographical patterns and cultural trends. The most significant coincidence is an intensification of human pressure, as noted in forest clearing and extensive land use, during several phases of the Middle Ages. At the Mediterranean level, the Montcortès record emerges as a unique sequence for the western sector of this biome that should be complemented with similar archives from the central and eastern Mediterranean. The most promising candidates for such sequences are discussed on the basis of available Mediterranean varved records. [Display omitted] • The longest, continuous and absolutely varve-dated lake record of the Mediterranean region. • High-resolution reconstruction of vegetation/landscape trends during the last 3000 years (Bronze Age-present). • Emphasis on the role of climatic and anthropogenic drivers, their feedbacks and synergies. • Detailed correlations with local archaeological evidence and historical documentation. • A potential paleoecological reference section for the western Mediterranean region. [ABSTRACT FROM AUTHOR]

The paper presents results of a palaeobotanical investigation of the borehole core Komorniki 97/72 from the Ruja lignite deposit, Lower Silesia. In the deposit lignites of three (2nd Lusatian, 2nd A Lubin, and 1st mid-Polish) middle Miocene groups of seams are present. The lignites of the 1st and 2nd groups are important correlation horizons throughout much of the Polish Lowlands and eastern Germany. The results of the palynological studies (spore–pollen, algae and fungi) and plant macroremains studies show that during the mid-Miocene mires' development, the vegetation was characteristic of wetlands (i.e., swamp and riparian forests, shrub bogs, and reed marshes) as well as mesophytic forests. The results were also used for palaeoclimatic investigation. The mean annual temperature (MAT), for each of the three sections, based on the coexistence approach (CA) method, was estimated in the range of 15.7–17.8 °C. Nevertheless, the frequency of thermophilous (palaeotropical and palaeotropical/warm-temperate) taxa indicate climate changes during the formation of the studied sediments. Composition of the spore–pollen spectra from the 2nd Lusatian seam (i.e., the presence of Meliaceae and Sapotaceae, which currently have pantropical distribution) show that the climate was humid and warm, close to subtropical. Later, many palaeotropical taxa disappeared, and the composition of the spore–pollen spectra indicates a warm temperate climate with slight fluctuations. Above the 1st mid-Polish seam, the climatic conditions changed in a way that did not favor the further formation of lignite deposits. These results correspond with the current understanding of climate change in the middle Miocene in Europe. • The Ruja deposit contains lignite of the three youngest groups of seams. • Middle Miocene vegetation and palaeoclimate of the Ruja area are discussed. • Palynological analysis and plant macroremains are used for the palaeointerpretations. • The results correspond with the current understanding of climate change in Europe. [ABSTRACT FROM AUTHOR]