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Past plant diversity dynamics can provide a historical perspective on biodiversity change and ecosystem dynamics as a guide to conservation management in the future. Pollen analysis is one of the most widely used approaches to reconstruct plant diversity change through time, but the representativeness of pollen diversity to plant diversity is not yet fully understood and especially in open landscapes. In this paper, we compare pollen assemblages from topsoil in the open landscapes of the Tibetan Plateau with the surrounding vegetation to investigate their compositional similarity and the correlations between their diversity (richness and evenness), and to evaluate the influence of climate variables, landscape characteristics, and human disturbance on the pollen diversity. The results show that pollen assemblages vary obviously in different vegetation types and they can represent their surrounding plant communities at low taxonomic levels. Pollen richness boarders a better match with plant richness than pollen evenness with plant evenness across the whole study area, but the correlation is weak (r adj 2 < 0.2, p < 0.001). Transforming plants into their pollen equivalents has little improvement for the correlations between pollen and plant richness/evenness. Pollen richness and evenness can capture well the trend in plant richness and evenness along the vegetation gradient, suggesting that they can be used as gamma (landscape scale) rather than alpha (local scale) diversity metrics in the study area. Mean annual precipitation (MAP), mean annual temperature (MAT), and patch richness (PatchS) are positively associated with pollen richness. MAP, PatchS, and human disturbance (HD) are significantly predictors for pollen evenness. These confirm that pollen richness and evenness can provide insights into past plant diversity dynamics and help evaluating the effects of climate and habitat changes and human disturbance on long timescales. • Pollen assemblages represent surrounding plant communities at low taxonomic levels. • Pollen diversity is reliable proxy for plant diversity at the landscape scale. • Vegetation shift is an important prerequisite in studying past plant diversity. • Pollen-equivalent transformation cannot improve pollen-plant diversity correlations. • Pollen diversity can indicate changes in past climate and habitat conditions. [ABSTRACT FROM AUTHOR]

Recent discoveries of several Mesolithic sites within the Dagsmosse Basin, south-central Sweden, offer an opportunity to study the lifestyle and skillsets of Mesolithic hunter-gatherer-fishers operating in wetland environments. In this paper, we present a combined archaeological and palaeoecological analysis of a Mesolithic fenland environment using Repetitive-Proxy Pollen Analysis (RPPA) of early Holocene sequences. Based on comparison of stratigraphic profiles from two cores within the basin, we infer that the variance in pollen composition and anthropogenic signals reflect variability in human/vegetation interactions in the fenland, at different distances to the main human dwelling at Jussberg (9.0–8.2 ka cal BP). Our study describes the socio-environmental relations within the wetland and adjacent terrestrial areas, providing a basis for tracking changes in forager interactions with their surroundings during the Mesolithic. Pollen analysis is consistent with the previously established sequence of settlement phases and extent as well as providing new data concerning the anthropogenic impacts on plant communities within the wetland including the use, reuse, and management of vegetation taxa. Correlations between palaeoecological and archaeological data demonstrate that forager communities (i) prevailed in the open fenland landscape between 9.3 and 8.2 ka cal BP, (ii) actively altered taxa composition through small-scale clearings of pine (Pinus), birch (Betula) and sedges (Cyperaceae) and (iii) reduced canopy cover, possibly to intentionally encourage the growth of taxa such as hazel (Corylus), but that also promoted the establishment of pioneer plants such as mugwort (Artemisia) and bracken (Pteridium). • Mesolithic foragers impacted forest and grassland vegetation around the Dagsmosse basin as well as the wetland formation. • HGF clearance and plant-use was perceivable at multiple spatial scales through comparative pollen analysis. • Human activity and movement within the middle Scandinavian inland changed throughout the Mesolithic and the 8.2 ka stadial. [ABSTRACT FROM AUTHOR]

Human impact on the coastal plain of Southeast China has been well studied over late Holocene timescales; however, an understanding of anthropogenic impact in mountainous regions is still lacking. In this paper, we present records of vegetation, fire, and human impact, spanning the past 4000 years, with a resolution of ∼40 years, obtained from an upland peatland in Southeast China. The results reveal that climate change (dominated by the evolution of the East Asia Monsoon) was the most critical factor controlling vegetation before 1.0 cal kyr BP, while human impact gradually emerged as the primary driver after 1.0 cal kyr BP in the mountains of Southeast China. As such, the record of anthropic impact in mountainous regions lagged behind the signal from the coastal plains by some 2000–4000 years. As the population migrating from northern China dispersed into the mountainous regions of Southeast China, demand for agricultural land promoted slash-and-burn cultivation and the destruction of broad-leaf forest. • Three climatic stages identified spanning 4.0 cal kyr BP based on pollen and charcoal analysis. • Significant anthropogenic impact on mountain vegetation of Southeast China occurred in 1.0 kyr BP, lagged coastal plains by 2000–4000 years. • The population migrating from northern China dispersed into the mountainous regions of southeastern China in 1.0 kyr BP, urgent demand for cultivated land. [ABSTRACT FROM AUTHOR]

The Permian formations of the South African Karoo Basin play a crucial role in understanding Gondwana's climate history during this time of major global changes. In this paper we present two data sets, one from the coal-bearing Vryheid Formation (Witbank Basin) and one from the Whitehill and Upper Prince Albert formations of the DP 1/78 core (NE Karoo). Our main goal was to study the vegetation changes during this period of global warming and test if the climatic signals could be used to correlate the basinal Ecca group facies with the fluvio-deltaic coal-bearing strata of the Witbank Basin. The palynological record of the No. 2 Coal Seam of the Vryheid Formation indicates a cold climate, fern wetland community, characteristic of lowland alluvial plains, and an upland conifer community in the lower part of the coal seam. Up section, these communities are replaced by a cool-temperate cycad-like lowland vegetation and gymnospermous upland flora. The data set of the DP 1/78 core is interpreted to represent a cool to warm temperate climate represented by a high amount of Gangamopteris and Glossopteris elements. Both data sets are very different in their composition, which can be explained by the differences in depositional environment; however, our findings reveal a different age of the studied assemblages and thus also suggest that both data sets represent different stages in the transition from icehouse to greenhouse during Permian times. As the stratigraphic correlation between the Main Karroo Basin and the peripheral basins is still under discussion, this paper provides new data to underpin the stratigraphic placement of the Whitehill Formation relative to the coal-bearing Vryheid Formation. [ABSTRACT FROM AUTHOR]

Understanding human impact on the vegetation of the Tibetan Plateau through the Holocene is important for developing strategies for sustainable ecosystem management in the region. In this paper, 53 pairs of surface-soil samples from inside and outside livestock enclosures were obtained from across the Tibetan Plateau to investigate the differences in pollen assemblages between grazed and ungrazed sites. This modern dataset was then applied to palynological records from four lakes in the northeast Tibetan Plateau region to investigate middle to late Holocene grazing history. Results show that modern grazing activities have a limited impact on the vegetation, although grazing activity leads to an increase in the pollen proportion of Cyperaceae, Artemisia , Ranunculaceae, Brassicaceae, Taraxacum -type, Fabaceae, and Saxifrageceae while representatives of Poaceae, Chenopodiaceae, and Aster -type pollen decrease. Application of these grazing indicators to the pollen spectra obtained from the four lake sites, together with other proxies, reveals that grazing activity only commenced during the last few hundred years in the northeast marginal areas of the Tibetan Plateau at c. 3000 m a.s.l, while there is no grazing signal in pollen records from above 4000 m a.s.l. Our study emphasises the importance of using multi-proxy methods in estimating signals of past human activity. • Pollen assemblage should be insensitive to grazing activities on the Tibetan Plateau. • Human impacts on vegetation at ∼3400 m a.s.l are limited to within a few centuries. • No significant pollen signal of grazing is revealed for the high-elevation areas. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the paleoclimatic and paleoenvironmental evolution of Laguna Yema in semi-arid Chaco region of Argentina over the past six hundred years. High resolution multiproxy studies of lake sediments utilize analyses of lithology, mineralogy, geochemistry, palynology, and are constrained by radiocarbon and gamma spectrometry dating. Laguna Yema sediments were mainly composed of well stratified fine sediments (silts and clays), with variable proportions of quartz, clays (illite) and feldspar (microcline and albite). Twelve light and heavy geochemical elements were registered. Most elements (Al, Si, K, Ti, Fe, Rb, Ba, and Br) are associated with illite and albite. Different material transport processes related to the changes in aridity and humidity of the basin were identified using the main mineralogical origins of geochemical elements. Palynological records indicate cycles of contraction and expansion of the lake, with an increase in concentration of Alternanthera aquatica during wet periods (expansion of lake), and an increase in Ambrosia , Poaceae and fern spores during dry periods (contraction of lake). These changes are linked to fluctuations in moisture conditions in the Subandean Mountains and semi-arid Chaco regions, in response to interactions between the South American Monsoon System (SAMS) and the South American Low Level Jet (SALLJ), which send warm and humid air to northern Argentina. In a regional context, the Laguna Yema records are in accordance with the analyses of the temporal and spatial pattern of moisture distribution for the last six centuries. • High-resolution variations of moisture conditions were registered by multiproxy lake sediments studies for the last 553 years. • Dissimilar material transport processes, related to the precipitation, were identified through mineralogy and geochemistry. • The palynological analyses allowed us to complement the paleohydrologic reconstruction in the basin. • The climatic model responds to the interconnection between the South American Monsoon System and South American Low Level Jet. [ABSTRACT FROM AUTHOR]

Abstract The Eocene was an interval of climate evolution, when the extreme high temperatures of the earliest Cenozoic gave way to a global cooling trend. Fine-grained lacustrine sediments of Eocene age from northeastern China represent an excellent archive to study long-term environmental and climatic changes at high-resolution. The Huadian Basin is a Cenozoic, fault-bounded basin in Jilin Province, northeastern China. Though small in area, it contains numerous oil shale- and coal-bearing layers, which provide an abundant Middle to Late Eocene palynoflora. Eighty-five palynomorph genera and one hundred palynomorph species were identified in the Huadian Formation, allowing to distinguish 4 palynozones. The nearest living relatives of the recovered palynomorph taxa suggest the presence of subtropical evergreen and deciduous broad-leaved forests during deposition of the Huadian Formation. Using the coexistence approach (CA), we calculated seven paleoclimatic parameters, which indicate a subtropical warm and humid climate with a mean annual temperature above 13.6 °C and a mean annual precipitation of at least 887 mm. However, the climate became cooler and drier during the transition from the lower Oil Shale Member to the upper Carbonaceous Shale Member. Palaeoclimatic data from the various Middle and Late Eocene basins of northeastern China (i.e., the Huadian, Fushun, Yilan, Hunchun and Jishu basins) were compared with data from North American and European basins. Middle Eocene climate in the Northern Hemisphere was generally warm and humid, and the mean annual temperature and precipitation in northeastern China were similar to those in North America, though slightly lower than those of Europe. Similar trends in temperature and precipitation on different continents support the existence of a global Mid-Eocene cooling event. This paper is the first systematic study of Middle to Late Eocene seasonality in the Huadian Basin. Our results show an apparent differentiation in both temperature and precipitation between summer and winter, supporting the view that the East Asian Monsoon was established in northeastern China already during the Middle to Late Eocene. This Middle and Late Eocene monsoon was likely driven by the development of Pacific trade winds and an alternating, seasonal high- and low-pressure system over Siberia. The climatic changes observed in our dataset, especially the precipitation changes, appear to have played an important role in controlling oil shale formation in the Huadian Basin. A warmer and more humid climate, with abundant precipitation and high subsidence rates, formed a deeper Huadian depositional lake. High productivity and stable stratification provided the abundant organic matter and favorable preservation conditions necessary for oil shale accumulation. Highlights • The Middle-Late Eocene palynoflora were firstly systematically studied in Huadian Basin. • We quantitatively estimated the Middle-Late Eocene climate based on CA method. • A globally cooler phase was recognized in the Middle Eocene. • Climate seasonality in the Middle-Late Eocene supports the EAM was already prevalent in NE China. • Changes in climate, especially precipitation, play an important role in oil shale formation. [ABSTRACT FROM AUTHOR]

A transition from widespread humid to more drought tolerant floras characterized tropical terrestrial ecosystems during the Permian (Cisuralian). Tregiovo (Southern Alps, N-Italy) is one of the very few well dated Kungurian (late Cisuralian) plant localities in Euramerica. It was located in eastern palaeoequatorial Pangea. Two units bearing fossil plant assemblages occur in finely laminated sediments deposited in a playa-lake environment. In this paper, the sedimentology of the Tregiovo Basin is reviewed, and new palaeobotanical, palynological and stable isotopic data are presented, in order to reconstruct the palaeoclimatic and palaeoenvironmental conditions of the Kungurian in the Southern Alps. Both fossil plant assemblages are dominated by conifers ( Hermitia , Feysia , Quadrocladus , Dolomitia ), together with sphenophytes ( Annularia ), ginkgophytes ( Sphenobaiera ), pteridosperms ( Peltaspermum ), taeniopterids and sphenopterids. These taxa, which occur with different abundances in the two plant assemblages, both indicate semi-arid conditions. Associated palynoflora, dominated by bisaccate pollen, and extremely rare spore occurrences, is consistent with the xerophytic character of the macroflora, and suggests that the fossil plant record was not affected by collection or preservation bias. Stable isotopic analyses of two stratigraphic sections reveal an upward trend of increasingly negative δ 13 C org (VPDB), which may correlate with roughly coeval records from marine and continental successions such as in North China and South Africa. This isotopic shift may be attributed to a global perturbation of atmospheric δ 13 C, although the influence of local environmental factors cannot be excluded. [ABSTRACT FROM AUTHOR]

This paper presents the results of a palynological investigation of the sands from upper Eocene (Priabonian) epicontinental marine strata at Łukowa, SE Poland. This locality represents an isolated spot of upper Eocene strata in the southern part of epicontinental Poland due to later uplift and erosion of this area. The sands studied yielded a well-preserved palynoflora, providing information about palaeovegetation and palaeoclimate after the Early Eocene Climate Optimum. During the study a total of 94 fossil species of palynomorphs were identified. The results indicate that the vicinity of the sedimentary basin was covered by vegetation with a significant portion of thermophilous taxa and containing many elements with East Asian affinities. The plant communities were composed of Platanus , Platycarya , Engelhardioideae, members of the Hamamelidaceae, Sapotaceae, Fabaceae, Oleaceae, Fagaceae (probably evergreen Quercus and Castanoideae), and Betulaceae families, as well as Salix , Carya , and others. Members of the Pinaceae family and Sciadopitys were components of coniferous or mixed forests. Taxodium , and presumably Glyptostrobus , together with Nyssa , might have covered areas with a higher groundwater level. The pollen of Milfordia and Aglaoreidia cyclops can probably be considered as representing marsh/freshwater vegetation. Cryptogams are represented mainly by ferns (including members of the Lygodiaceae and Schizaeaceae, probably as well as Gleicheniaceae and Cyatheaceae families) and Lycopodiaceae (including Lycopodiella ). The presence of frequent pollen and spores of the genera presently growing under tropical and subtropical climatic conditions and the presence of several taxa characteristic for swamps indicate that the climate during deposition of the sediments studied was warm and humid. The mean annual temperature of 17.2–23.1 °C was estimated on the basis of Coexistence Approach method. [ABSTRACT FROM AUTHOR]

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]

The widespread perception that buckwheat ( Fagopyrum esculentum and F. tataricum ) did not occur in western Eurasia prior to the Late Medieval is challenged by numerous pollen finds. We traced some 240 localities from the area with pollen or macrofossils attributed to Fagopyrum in (often much) earlier time-slices. This paper evaluates various explanations for these finds within the context of palaecological methods, vegetation history, and cultural development. The clear morphological characteristics make large-scale misidentification of the pollen unlikely. Although some records are suspect, contamination is improbable for the vast majority of the pollen diagrams. Also long-distance transport of pollen of Fagopyrum snowdenii or Oxygonum from Africa seems unlikely, as the pollen rain of that continent hardly contains that pollen. The option that Fagopyrum was present in western Eurasia already much earlier than the Late Medieval must therefore be seriously considered. Cultivated species may have reached the area by trade between the Mediterranean and eastern Chinese realms, which was regular since 2000 BCE. As the low pollen values argue against large scale cultivation, the taxon may merely have occurred as a weed, or its pollen was transported with other products and subsequently re-emitted. The pervasive notion that buckwheat was cultivated on large scale by the Scythians in the Ukrainian realm since 800 BCE is highly ambiguous and probably wrong. There are some indications that wild Fagopyrum or a related taxon may have occurred widespread in Eurasia during the Pleistocene glaciations and the early/middle Holocene, i.e. predating 2000 BCE. [ABSTRACT FROM AUTHOR]

Studies dealing with the reconstruction of Holocene climate change of tropical areas are scarce. Of these, multi-proxy investigations using peatlands are still absent. In this paper, we present the Holocene record of environmental changes in central–eastern Brazil reconstructed from a core sampled in Pau de Fruta mire (Serra do Espinhaço Meridional, Brazil). We combined palynological and geochemical analyses, supported by core stratigraphy, 14 C dating and multivariate statistics. The location of the mire is ideal because it is in an area which is directly associated with the South Atlantic Convergence Zone (SACZ). Six main phases of change suggested by vegetation and local and regional landscape dynamics were described. In phase I (~ 10,000–7360 cal. yr BP) the climate was very wet and cold and was accompanied by soil instability in the mire catchment (severe local erosion) and the 8.2 ka event was easily recognizable by a large increase in the deposition of regional dust. Phase II (~ 7360–4200 cal. yr BP) was characterized by wet and warm conditions, catchment soil stability and enhanced deposition of regional dust. In phase III (~ 4200–2200 cal. yr BP), climate was dry and warm and soil erosion in the catchment increased again. In phase IV (~ 2200–1160 cal. yr BP) dry and punctuated cooling was reconstructed, together with enhanced deposition of regional dust. Phase V (~ 1160–400 cal. yr BP) reflects sub-humid climatic conditions (like the current climate), the lowest inputs of local and regional dust and the largest accumulation of peat in the mire. While in phase VI (< ~ 400 cal. yr BP) sub-humid conditions continued but both local and regional erosion significantly increased. Our results demonstrate that the tropical peatlands of Serra do Espinhaço Meridional contain relevant records of Holocene climate changes, and that a multi-proxy approach offers good opportunities for a detailed reconstruction of palaeoenvironments. [ABSTRACT FROM AUTHOR]

In this paper we present the results of a multidisciplinary study performed in the Carrasqueira valley, a tributary of the River Sado (SW Portugal), aimed at characterising the Holocene environmental conditions during the late Mesolithic occupation of this valley. Our findings are based on a 13.5 m long sediment core (Arez3) collected on the alluvial plain close to a late Mesolithic shell midden, the Arapouco site. The results of the multiproxy analyses (texture, magnetic susceptibility, organic composition and chemistry, n -alkanes and palynology) point to a greater marine influence between ca. 8850 cal yrs. B.P. (at the core base) and ca. 7450 cal yrs. B.P. (at 750 cm below mean sea level (MSL)) and the existence of an environment similar to the present-day central estuarine basin. At this point in time, sedimentation rates were lower than the rate of sea-level rise, resulting in the formation of a drowned area with intertidal environments developing on the less incised margins. After 7040 cal yrs. B.P. the contribution of organic matter from terrestrial plants and freshwater phytoplankton to the sediment increased, reflecting a change in the sedimentary pattern, with the estuarine environments progressively giving way to freshwater environments. After the Middle Holocene (ca. 6530 cal yrs. B.P.), negative shifts of δ15N to values ~0‰ point to hyper-eutrophication and cyanobacteria bloom episodes under backswamp conditions. According to these results, the estuarine environment prevailed in the area until 7040 cal yrs. B.P. (5090 cal yrs. B.C.; 390 cm below MSL), i.e., during the Mesolithic occupation of the valley, allowing for the occurrence and for the exploitation of marine shellfish and fish by these hunter-gatherer communities at the proximity of the downstream occupation areas. [Display omitted] • The Sado estuary was larger in the Early-Mid Holocene in response to sea-level rise. • Estuarine conditions extended until more than 52 km from the present-day estuary inlet. • Brackish environments were present in the Late Mesolithic occupied area. • Sado has high mean sedimentation rates (SR), reflecting its Mediterranean character. • The SR only surpassed the sea-level rise rate between 7120 and 6800 cal yrs. B.P. [ABSTRACT FROM AUTHOR]

Past temperature changes in tropical mountain regions are commonly inferred from vertical elevational shifts of montane indicator taxa in the palynological record. However temperature is one of several abiotic factors driving the low-elevational limits of species and many montane taxa can occur in warmer lowlands by tracking appropriate habitat types, especially highly flooded wetlands. In this paper we explore ways in which lowland habitat heterogeneity might introduce error into paleo-temperature reconstructions, based on field data of seven modern peatland vegetation communities in the southern Peruvian Amazon (~ 200 masl). Peat-rich substrates are common edaphic transitions in pollen cores and provide detailed records of past vegetation change. The data show that indicators of modern peatlands include genera with montane as well as lowland distributions, while indicators of surrounding forests on mineral substrates have predominantly lowland distributions. Based on family-level analyses we find that modern peatland vegetation communities have taxonomic compositions appearing to be 389 m to 1557 m (mean = 1050 ± 391 m) above their actual elevations due to a high abundance and number of families with high elevation optima. We interpret the relatively higher prevalence of montane elements in modern peatlands as habitat tracking of a conserved montane niche on heterogeneous lowland landscapes. We suggest that both high moisture availability and stressful edaphic conditions of peatland habitat may explain the montane bias observed. To the extent that fossilization provides a better record of past vegetation that occurred proximate to the site of deposition, we suggest that habitat tracking of montane elements may introduce a cool bias in lowland paleo-temperature reconstructions based on pollen proxies. [ABSTRACT FROM AUTHOR]

Pollen analysis provides a key technique for the reconstruction of post-glacial vegetation. Modern observation of the plant-pollen relationship, through the use of surface pollen studies, is an instrumental process for informing these reconstructions. However, results from surface pollen studies suggest that the diversity of pollen assemblages is rarely a faithful representation of the diversity of the local vegetation. Pollen diversity at high altitude is determined by both the composition and density of the local vegetation and long-distance pollen. This paper examines the relationship between floristic and palynological diversity using surface samples collected from alpine communities found on three glacier forelands (Austerdalsbreen, Storbreen and Grjøtbreen) in the Jostedalsbreen-Jotunheimen region of Norway. Several diversity indices indicate the complexity of the relationship between palynological and floristic diversity. This is accentuated in open, high altitude, sparsely-vegetated sites, where palynological diversity is a measure of the diversity of the long-distance pollen assemblage rather than the diversity of the local vegetation. Even at sites on older moraines at Storbreen and Austerdalsbreen, where the vegetation is denser and more diverse, the relationship is not simple but depends on pollen production of the taxa that dominate the local vegetation. On Storbreen foreland, for example, the diversity of small, insect-pollinated plants growing locally is poorly represented in the pollen assemblage which is dominated by long-distance arboreal pollen. The surface pollen results were compared with fossil pollen data from a palaeosol at Memurubreen in Eastern Jotunheimen. DCA ordination indicates that the fossil pollen spectra are distinct from the modern samples, due to differences in the pollen assemblages, probably related to lower treelines in the past associated with climatic cooling or human impact. The palaeosol samples are most similar to modern samples from heath and snowbed communities, found on older terrain at Grjøtbreen and Storbreen, and the diversity indices also show strong similarities with these communities. The potential for improvements in methodology to increase resolution is considered. • Floristic and palynological diversity are compared using several diversity indices. • Pollen source and local vegetation influence floristic & palynological diversity. • High-altitude sites present a challenge since regional pollen dominates samples. • Diversity of Holocene and modern heath and snowbed samples shows strong similarities. • Comparison of Holocene & modern pollen diversity offers insight into past vegetation. [ABSTRACT FROM AUTHOR]

Proximal alluvial sediments represent a useful sedimentary archive to reconstruct the tectono-climatic history of continental rift basins. However, poor dating of coarse fluvial successions usually prevents high-resolution distinction of tectonic and climatic processes, and thus good determination of process rates. This paper presents a dating study of Plio-Pleistocene Kalavryta river system during the early history of the Corinth Rift (northern Peloponnese, Greece) based on magnetostratigraphy and palynology. This river system developed across several active normal fault blocks that are now uplifted along the southern rift margin. The detailed sedimentary record constrains alluvial architectures from the proximal basin to the river outlet where small deltas built into a shallow lake. In four magnetostratigraphy sections the correlation to the reference scale relies on the identification of the Gauss/Matuyama magnetic reversal and biostratigraphic elements. The river system developed between about 3.6 to 1.8 Ma, with sediment accumulation rates (SARs) ranging from 0.40 to 0.75 mm yr−1. SAR is lower in the alluvial fans than in the deltaic system, and higher at the centre of the normal fault depocentres than at the fault tip. By comparison with worldwide Cenozoic SARs, our values are higher but lie in the same range as those determined in coarse alluvial foreland basins. Moreover, in the context of overfilled intra-mountainous rift basins, these rates are minimum values and can be used as a proxy for accommodation rate. Therefore, early rift stratal wedges and growth synclines attest high sedimentation rates and also high rates of tectonic processes. Finally, in the distal river system, floral compositions and changes of vegetation deduced from palynological data are coherent with alternating fluvio-deltaic and shallow lacustrine deposits, which are linked to relative base level variations. Dry/cool climate is preferentially recorded during periods of low lake level, while the warm/moist climate is mainly recorded in prodelta deposits during periods of high lake level. This correlation suggests that, despite the dominant control of active faulting, climate is a key control of syn -rift stratigraphic architectures. • Basal syn-rift succession in the western Corinth rift from 3.6 Ma and 1.8 Ma. • Sediment accumulation rates 0.40–0.75 mm yr−1 varying with the alluvial architectures. • High rates of processes explained by high sediment supply from the antecedent Kalavryta river system. • Pollen record in the deltaic succession with alternating vegetation of interglacial and glacial periods. • The Valimi palynology section: a rare climatic record in syn-rift alluvial succession. [ABSTRACT FROM AUTHOR]

The varved sediments of Lake Montcortès (central pre-Pyrenees) have provided a continuous high-resolution record of the last ca. 3000 years. Previous chronological and sedimentological studies of this record have furnished detailed paleoenvironmental reconstructions. However, palynological studies are only available for the last millennium, when the landscape around the lake had already been transformed by humans. Therefore, the earlier vegetation of Montcortès and the history of its anthropogenic transformations remain unknown. This paper presents a palynological analysis of the interval between the Late Bronze Age and the Early Medieval period, aimed at recording preanthropic conditions, anthropization onset and the further landscape transformations. During the Late Bronze Age (ca. 1100 BCE to 770 BCE), the vegetation did not show any evidence of human impact. The decisive anthropogenic transformation of the Montcortès catchment vegetation and landscape started at the beginning of the Iron Age (770 BCE) and continued during Roman and Medieval times in the form of recurrent burning, grazing, cultivation, silviculture and hemp retting. Some intervals of lower human pressure were recorded, but the original vegetation never returned. The anthropization that took place during the Iron Age did not cause notable changes in the sediment yield to the lake, but a significant limnological shift occurred, as manifested in the initiation of varve formation, a process that has been continuous until today. Climatic shifts seem to have played a secondary role in influencing vegetation and landscape changes. These results contrast with previous inferences of low anthropogenic impact until the Medieval Period, at a regional level. Similar studies may be developed on other mountain ranges to verify whether landscape anthropization occurred earlier than previously thought, and to verify the potential occurrence of elevational gradients in the anthropization of mountain landscapes. • Palynological analysis of Lake Montcortès varved sediments (1100 BCE–770 BCE). • Unexpected Iron Age, rather than Medieval, landscape anthropization. • Shifting land use and variable human pressure until the Roman and the Migration periods. • Further intensification of human activities during the early Medieval Period. • A possible general anthropization pattern for the Pyrenees and other mountain ranges. [ABSTRACT FROM AUTHOR]

Terrestrial deposits of the Triassic-Jurassic transition are well developed in the Junggar Basin, located in the Haojiagou Valley of Urumqi, Xinjiang Uygur Autonomous Region of Northwest China. This paper describes the palynology of a 10 m thick lignite bed from the Upper Triassic Haojiagou Formation (Rhaetian) with the aim of reconstructing the palaeovegetation and palaeoenvironment of a peat-forming wetland near the Triassic-Jurassic boundary. The palynoflora contains both Eurasian and Gondwanan elements, and is dominated by the spores and pollen of Bennettitales, Corystospermales, Ginkgoales, and Gleicheniales. At the Triassic/Jurassic boundary (Hettangian), the palynoflora significantly changes as Cyatheales spores become the dominant elements. We analyze assemblages in terms of an Eco-Plant model, which assigns the parent plants of the palynomorphs into five groups based on humidity and four groups based on temperature, and uses multivariate statistical analyses to infer palaeoclimate and palaeoenvironmental conditions. Results suggest that the palaeoclimate of the Rhaetian was generally wet and subtropical with short seasonal drought periods. Our analysis shows that an Eco-Plant model may be a useful tool to reveal past vegetation patterns and climate changes, applicable to other Mesozoic assemblages. • Palynomorph study based on scanning electron microscope and light microscope. • Using Eco-Plant model to reconstruct Mesozoic humidity and temperature. • Palaeoenvironmental reconstruction near the Triassic-Jurassic boundary. • High-resolution Mesozoic palynomorph study • The Upper Triassic terrestrial Haojiagou Formation. [ABSTRACT FROM AUTHOR]

This paper presents pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves in southern Spain (Granada), with the aim of reconstructing the environmental conditions of these hominin sites. The LV coprolites are radiocarbon dated from c. 37,890 to 6980 cal yr BP, and the Car coprolites from c. 31,063 to 7861 cal yr BP. Overall, the palaeoecological scenario inferred from both coprolite series display similar patterns, with Pinus , Poaceae, and Artemisia as dominant during the full Pleistocene, and an important contribution of Quercus in the most recently dated coprolite samples. While the palynology is consistent with results of former investigations on the past environments in the region as obtained from other deposits (peat bogs, cave infills), the Late Glacial and Holocene chronology of several coprolites in both sites is in conflict with the generally accepted timing of extinction of Crocuta in western Europe. A discussion on the taphonomical processes and potential sources of carbon contamination of the radiocarbon samples is provided. The correlation between pollen from coprolites and from sedimentary records, and the paucity of the fossil bone record suggests nevertheless, that a late survival of Crocuta in southern Spain should not be categorically discarded. • New pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves. • The palaeoecological scenario inferred from both coprolite series display similar patterns. • Timing of extinction of Crocuta in western Europe. • A late survival of Crocuta in southern Spain should not be categorically discarded. [ABSTRACT FROM AUTHOR]

The Paraná Basin, the largest basin in South America, received glacially derived sediments during the Late Palaeozoic Ice Age (LPIA) of the Gondwana supercontinent. Despite the importance of this basin for understanding the continental development of the Gondwana glaciation, and the fact that ca. 95% of this basin is not exposed at the surface, few attempts have been made to connect the exposed glacial strata to the subsurface record. In this paper, exposures of glacial cycles in the Upper Itararé Group in Santa Catarina State, southern Brazil, are analyzed, locally correlated and then linked to the three major glacial cycles previously described from subsurface studies along the basin. Together study areas (Doutor Pedrinho and Vidal Ramos) record five, partially comparable shorter glacial subcycles (relative to the major glacial cycles). These series comprise coarse-grained subaqueous outwash deposits, turbidite sand sheets, marine shales, and diamictites, the latter mostly derived from delta slope failure and ensuing resedimentation. In addition to sedimentological and genetic stratigraphic description and analysis, preliminary age determination based on the palynological content is also presented. Besides, a regional correlation of the described succession to the subsurface record is proposed based on well logs and core information. All the palynomorph associations identified from the exposed successions, which represent the upper third part of the Itararé Group, are related to the Subzone Protohaploxypinus goraiensis , base of the Vittatina costabilis Zone. This zone and correlated ones along the Gondwana are considered Early Permian in age. However, a first isotopic age recently obtained for the upper Itararé Group and published elsewhere is considered within a regional stratigraphic framework once it leads to new insights in terms of the LPIA time span recorded in the Paraná Basin. • Late Palaeozoic glacial cycles in western Gondwana • Correlation of long and short-term glacial cycles • Palynology of the upper Itararé group • Sequence stratigraphy of glacially-related successions [ABSTRACT FROM AUTHOR]