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In this paper, we describe palynological assemblages in the Middle Miocene (Serravallian) Kenslow Member of the Brassington Formation at Bees Nest Pit, near Brassington, Derbyshire, U.K., and infer vegetation types and their palaeoclimate implications. The limited lateral extent of the 1.33 m-thick succession of clay and lignite, and its position surrounding fragments of a large tree trunk, suggests that the succession may have accumulated within a tree throw hole or possibly within a shallow stagnant pond, although aquatic lacustrine palynomorphs have not been identified to confirm this latter hypothesis. The stratigraphical distribution of palynological assemblages, based on 58 samples allows reconstruction of a wetland succession. Two pollen zones were identified using CONISS cluster analysis, and a predominantly warm-temperate and mixed mesophytic forest biome was recognised with Tsuga conifer pollen-types being dominant (<42%) in both pollen zones. Changes in the make-up of this forested wetland were in response to local environmental changes rather than major climatic shifts. Wetland development culminated in the formation of a relatively open shrub and reed-dominated mire which produced the lignite-precursor peat. Applying the Co-existence Approach, Mean Annual Temperature was 15.6–21.7 °C and Mean Annual Precipitation was 703–1682 mm indicating a warm-temperate to subtropical palaeoclimate, and both parameters show no significant change through the section. Findings suggest that, following the Middle Miocene Climatic Optimum, the Serravallian climate of the northwestern margin of Europe remained much wetter than Central Europe, where more arid climates have been reconstructed, and this difference may have been due to the influence of the proto-North Atlantic Current. • We present a fossil record using a lignite and clay unit from the Kenslow Member. • We present the first reconstruction of a wetlands in the UK Miocene reconstruction record. • Transition from a Tsuga -dominant mixed mesophytic forest to a wetland occurred. • Palaeoclimate variables varied little and suggested frost-free conditions. • High precipitation reconstructions were caused by the proto-North Atlantic Current. [ABSTRACT FROM AUTHOR]

Understanding the nature of moisture availability in the Eocene, Oligocene, and Miocene of Antarctica is imperative for climate reconstructions and for understanding the potential influence of future climate change on modern landscapes. Previous studies have used traditional palynological techniques, fossil leaf margins, hydrogen isotope leaf waxes, and palynomorph δ 13 C values to indicate changes in moisture on the southernmost continent. Here, we explore the relationship between pollen width (equatorial diameter) and climate as a potential indicator of changes in moisture availability in Antarctica, a technique that had not been widely applied previously. To date, studies of pollen grain size response to environmental stress and the applicability of using fossil pollen grain size as a climate change proxy are limited. In this paper, we explore the relationship between pollen grain size and environmental stress (desiccation intensity) and whether such a relationship can be applied to fossil pollen from Antarctica. We measured the widths of 157 modern specimens of Nothofagus spp. (the genus of Southern beech) pollen from throughout the Southern Hemisphere and compared them with mean annual precipitation records to assess the relationship between pollen grain size and moisture availability. The widths of 458 Antarctic Nothofagidites lachlaniae -complex pollen grains (from Eocene, Oligocene, and Miocene cores) were then measured and compared to other paleoenvironmental proxies to evaluate whether or not a significant trend in size variability can be associated with a change in moisture availability through geological time. Modern data show a significant relationship between decreased moisture availability and increased pollen grain size and are consistent with a previous study, providing confidence for using changes in pollen grain size as an indicator of moisture. Fossil data show a 23% increase in average pollen grain size from the late Eocene through the early to mid Miocene, indicating a decrease in moisture availability in Antarctica during this time. [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]