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A novel, yet simple, airborne microplastic (MP) sampling approach using global pollen monitoring equipment was applied to identify, characterise and quantify outdoor airborne MPs for the first time. Modification of Burkard spore trap tape adhesive provided particle capture and facilitated downstream spectroscopy analysis. 36 polymer types were identified from a total of 21 days sampling using Burkard spore traps at two locations (United Kingdom and South Africa). MPs were detected in 95 % of daily samples. Mean MP particle levels were 2.0 ± 0.9 MP m -3 (11 polymer types) in Hull (U.K.), during March, 2.9 ± 2.0 MP m -3 (16 types) in Hull in July, and 11.0 ± 5.7 MP m -3 (29 types) in Gqeberha, (S.A.) in August 2023. The most abundant polymer type was nylon (Gqeberha). The approach was compared with two passive sampling methods whereby 27 polymer types were identified and of these, 6 types were above the limit of quantification (LOQ), with poly(methacrolein:styrene) (PMA/PS) the most abundant. Irregularly shaped MPs < 100 µm in length were predominant from all sampling approaches. For the first time, airborne MPs were chemically characterised and quantified using volumetric pollen sampling equipment, representing a viable approach for future airborne MP monitoring., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Methods of reconstructing changes in plant traits over long time scales are needed to understand the impact of changing environmental conditions on ecosystem processes and services. Although Holocene pollen have been extensively used to provide records of vegetation history, few studies have adopted a functional trait approach that is pertinent to changes in ecosystem processes. Here, for woody and herbaceous fen peatland communities, we use modern pollen and vegetation data combined with pollen records from Holocene deposits to reconstruct vegetation functional dynamics. The six traits chosen (measures of leaf area-to-mass ratio and leaf nutrient content) are known to modulate species' fitness and to vary with changes in ecosystem processes. We fitted linear mixed effects models between community weighted mean (CWM) trait values of the modern pollen and vegetation to determine whether traits assigned to pollen types could be used to reconstruct traits found in the vegetation from pollen assemblages. We used relative pollen productivity (RPP) correction factors in an attempt to improve this relationship. For traits showing the best fit between modern pollen and vegetation, we applied the model to dated Holocene pollen sequences from Fenland and Romney Marsh in eastern and southern England and reconstructed temporal changes in trait composition. RPP adjustment did not improve the linear relationship between modern pollen and vegetation. Leaf nutrient traits (leaf C and N) were generally more predictable from pollen data than mass-area traits. We show that inferences about biomass accumulation and decomposition rates can be made using Holocene trait reconstructions. While it is possible to reconstruct community-level trends for some leaf traits from pollen assemblages preserved in sedimentary archives in wetlands, we show the importance of testing methods in modern systems first and encourage further development of this approach to address issues concerning the pollen-plant abundance relationship and pollen source area., Competing Interests: The authors have declared that no competing interests exist.

Vegetation reconstructions from palaeoecological records depend on adequate understanding of relationships between modern pollen, vegetation and climate. A key parameter for quantitative vegetation reconstructions is the Relative Pollen Productivity (RPP). Differences in both environmental and methodological factors are known to alter the RPP estimated significantly, making it difficult to determine whether the underlying pollen productivity does actually vary, and if so, why. In this paper, we present the results of a replication study for the Bashang steppe region, a typical steppe area in northern China, carried out in 2013 and 2014. In each year, 30 surface samples were collected for pollen analysis, with accompanying vegetation survey using the "Crackles Bequest Project" methodology. Sampling designs differed slightly between the two years: in 2013, sites were located completely randomly, whilst in 2014 sampling locations were constrained to be within a few km of roads. There is a strong inter-annual variability in both the pollen and the vegetation spectra therefore in RPPs, and annual precipitation may be a key influence on these variations. The pollen assemblages in both years are dominated by herbaceous taxa such as Artemisia, Amaranthaceae, Poaceae, Asteraceae, Cyperaceae, Fabaceae and Allium. Artemisia and Amaranthaceae pollen are significantly over-represented for their vegetation abundance. Poaceae, Cyperaceae and Fabaceae seem to have under-represented pollen for vegetation with correspondingly lower RPPs. Asteraceae seems to be well-represented, with moderate RPPs and less annual variation. Estimated Relevant Source Area of Pollen (RSAP) ranges from 2000 to 3000m. Different sampling designs have an effect both on RSAP and RPPs and random sample selection may be the best strategy for obtaining robust estimates. Our results have implications for further pollen-vegetation relationship and quantitative vegetation reconstruction research in typical steppe areas and in other open habitats with strong inter-annual variation., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Quantitative reconstructions of vegetation abundance from sediment-derived pollen systems provide unique insights into past ecological conditions. Recently, the use of pollen accumulation rates (PAR, grains cm−2 year−1) has shown promise as a bioproxy for plant abundance. However, successfully reconstructing region-specific vegetation dynamics using PAR requires that accurate assessments of pollen deposition processes be quantitatively linked to spatially-explicit measures of plant abundance. Our study addressed these methodological challenges. Modern PAR and vegetation data were obtained from seven lakes in the western Klamath Mountains, California. To determine how to best calibrate our PAR-biomass model, we first calculated the spatial area of vegetation where vegetation composition and patterning is recorded by changes in the pollen signal using two metrics. These metrics were an assemblage-level relevant source area of pollen (aRSAP) derived from extended R-value analysis (sensu Sugita, 1993) and a taxon-specific relevant source area of pollen (tRSAP) derived from PAR regression (sensu Jackson, 1990). To the best of our knowledge, aRSAP and tRSAP have not been directly compared. We found that the tRSAP estimated a smaller area for some taxa (e.g. a circular area with a 225 m radius for Pinus) than the aRSAP (a circular area with a 625 m radius). We fit linear models to relate PAR values from modern lake sediments with empirical, distance-weighted estimates of aboveground live biomass (AGLdw) for both the aRSAP and tRSAP distances. In both cases, we found that the PARs of major tree taxa – Pseudotsuga, Pinus, Notholithocarpus, and TCT (Taxodiaceae, Cupressaceae, and Taxaceae families) – were statistically significant and reasonably precise estimators of contemporary AGLdw. However, predictions weighted by the distance defined by aRSAP tended to be more precise. The relative root-mean squared error for the aRSAP biomass estimates was 9% compared to 12% for tRSAP. Our results demonstrate that calibrated PAR-biomass relationships provide a robust method to infer changes in past plant biomass. [ABSTRACT FROM AUTHOR]

A promising method of reconstructing past vegetation from pollen records uses mathematical models of the relationship between pollen and vegetation. These can be calibrated using the extended R-value (ERV) approach on datasets of modern pollen assemblages and related vegetation surveys. This study presents the results of calibrating the pollen-vegetation models for non-arboreal pollen types in alpine meadow habitats on the Tibetan Plateau. Surface soil samples were analysed for pollen and the surrounding vegetation was recorded at 30 randomly located sites in the Zoige basin, northeastern Tibetan Plateau. ERV analysis found that the most reliable results were obtained when using ERV sub-models 1 and 2, and distance-weighting the vegetation data by applying the taxon-specific Prentice–Sutton method. The relevant source area of pollen for these soil samples was found to be ca. 200 m. Relative pollen productivities (RPP) of 15 non-arboreal taxa were estimated relative to Cyperaceae (RPPCyp). The taxa can be divided into three groups according to their RPPs, those with high RPPCyp values > 1.68 (Thalictrum, Artemisia, Caryophyllaceae, Chenopodiaceae and Plantago), those with moderate values (0.42–0.62) (Taraxacum-type, Apiaceae, Polygonum and Aster-type), and those with low values < 0.4 (Gentianaceae, Potentilla, Brassicaceae, Saussurea-type and Poaceae). The RPP values obtained from our study differ from those of previous studies in other parts of China, and form the basis for future reconstruction of palaeovegetation on the Tibetan Plateau through model-based methods, such as the Landscape Reconstruction Algorithm, or Multiple Scenario Approach. [ABSTRACT FROM AUTHOR]

Environmental reconstructions from pollen records collected within archaeological landscapes have traditionally taken a broadly narrative approach, with few attempts made at hypothesis testing or formal assessment of uncertainty. This disjuncture between the traditional interpretive approach to palynological data and the requirement for detailed, locally specific reconstructions of the landscapes in which people lived has arguably hindered closer integration of palaeoecological and archaeological datasets in recent decades. Here we implement a fundamentally different method for reconstructing past land cover from pollen records to the landscapes of and around the Somerset Levels and Moors—the Multiple Scenario Approach (MSA)—to reconstruct land cover for a series of 200-year timeslices covering the period 4200–2000 cal BC. Modelling of both archaeological and sediment chronologies enables the integration of reconstructed changes in land cover with archaeological evidence of contemporary Neolithic human activity. The MSA reconstructions are presented as a series of land cover maps and as graphs of quantitative measures of woodland clearance tracked over time. Our reconstructions provide a more nuanced understanding of the scale and timing of Neolithic clearance than has previously been available from narrative-based interpretations of pollen data. While the archaeological record tends to promote a view of long-term continuity in terms of the persistent building of wooden structures in the wetlands, our new interpretation of the palynological data contributes a more dynamic and varying narrative. Our case study demonstrates the potential for further integration of archaeological and palynological datasets, enabling us to get closer to the landscapes in which people lived. [ABSTRACT FROM AUTHOR]

Reconstructing land cover from pollen data using mathematical models of the relationship between them has the potential to translate the many thousand pollen records produced over the last 100 years (over 2300 radiocarbon-dated pollen records exist for the UK alone) into formats relevant to ecologists, archaeologists and climate scientists. However, the reliability of these reconstructions depends on model parameters. A key parameter is Relative Pollen Productivity (RPP), usually estimated from empirical data using 'Extended R Value analysis' (ERV analysis). Lack of RPP estimates for many regions is currently a major limitation on reconstructing global land cover. We present two alternatives to ERV analysis, the Modified Davis Method and an iteration method, which use the same underlying model of the relationship between pollen and vegetation to estimate RPP from empirical data, but with different assumptions. We test them in simulation against ERV analysis, and use a case study of a problematic empirical dataset to determine whether they have the potential to increase the speed and geographic range of RPP estimation. The two alternative methods are shown to perform at least as well as ERV analysis in simulation. We also present new RPP estimates from southeastern sub-tropical China for nine taxa estimated using the Modified Davis Method. Adding these two methods to the 'toolkit' for land cover reconstruction from pollen records opens up the possibility to estimate a key parameter from existing datasets with less field time than using current methods. This can both speed up the inclusion of more of the globe in past land cover mapping exercises such as the PAGES Landcover6k working group and improve our understanding of how this parameter varies within a single taxon and the factors control that variation. [ABSTRACT FROM AUTHOR]

Pollen dispersal and deposition (PDD) modelling has been instrumental in reconstructing historical vegetation in temperate regions, but its application has been limited in the tropics where there is greatest uncertainty in past land cover change. Here, we apply PDD modelling to Amazonian savanna and forested ecosystems. Empirical pollen data from lakes situated in southwestern Amazonia were used to calibrate the PDD model for a two-component landscape of forest and non-forest. The PDD model was then used to simulate pollen assemblages for different combinations of landscape arrangements (the multiple scenario approach) that reflect possible anthropogenic and climate-driven forest cover change in the late-Holocene. We show that pollen records from large Amazonian lakes vary greatly in their sensitivity to forest loss depending on the baseline forest cover. Lakes in landscapes containing >80% forest will detect small reductions (5% of total cover), but this sensitivity degrades rapidly with forest cover loss. There are a wide range of uncertainties in pollen reconstructions from mosaic and ecotonal landscapes. In forest-savanna mosaics, large reductions of forest cover could be undetectable through the pollen record. In ecotonal landscapes, the relationship between forest cover and its representation in the pollen record rapidly weakens with increasing distance from the forest boundary. Further application of PDD modelling in combination with the multiple scenario approach can address the uncertainties in pollen-based reconstructions of past land cover in the tropics, but require further investment and development. [ABSTRACT FROM AUTHOR]

This paper reviews recent advances in the reconstruction of woodland cover from palynological data. Pollen sequences record the vegetation cover of past landscapes, but translating a pollen diagram into a landscape reconstruction is not straightforward. This paper focuses on the use of pollen records to address three archaeologically relevant problems, the detection of woodland presence and extent in a largely open landscape, the reconstruction of the habitat context of a specific archaeological site, and the detection of woodland management. Research seeking to quantify past land-cover using models of pollen dispersal and deposition has led to the development of algorithms and computer software linking maps of the arrangement of land-cover with simulated pollen records at possible coring points. This software can be used to carry out thought experiments and test competing hypotheses, and also underpins the Multiple Scenario Approach to the reconstruction of past land-cover. Modern datasets of pollen surface samples and associated vegetation abundances are needed to calibrate these models, and can also provide insights into how the pollen record ‘sees’ landscapes, and therefore aid interpretation of past pollen records. We demonstrate how simulation approaches and surface sample studies are improving the scientific basis of reconstruction of past landscapes, and how these approaches offer new opportunities for communication and collaboration between archaeologists and environmental specialists. [ABSTRACT FROM AUTHOR]

The effects of repeated survey and fieldwork timing on data derived from a recently proposed standard field methodology for empirical estimation of relative pollen productivity (RPP) have been tested. Seasonal variations in vegetation and associated pollen assemblages were studied in three contrasting cultural habitat types; semi-natural ancient woodlands, lowland heaths, and unimproved, traditionally managed hay meadows. Results show that in woodlands and heathlands the standard method generates vegetation data with a reasonable degree of similarity throughout the field season, though in some instances additional recording of woodland canopy cover should be undertaken, and differences were greater for woodland understorey taxa than for arboreal taxa. Large differences in vegetation cover were observed over the field season in the grassland community, and matching the phenological timing of surveys within and between studies is clearly important if RPP estimates from these sites are to be comparable. Pollen assemblages from closely co-located moss polsters collected on different visits are shown to be variable in all communities, to a greater degree than can be explained by the sampling error associated with pollen counting, and further study of moss polsters as pollen traps is recommended. [ABSTRACT FROM AUTHOR]

The long-term goal of pollen analysis has always been the reconstruction of past vegetation mosaics. However, the pollen signal is spatially integrated, and ecologically distinct vegetation structures can produce identical pollen signals. This paper proposes an iterative approach to reconstruction, the Multiple Scenario Approach, which involves creating a large number of hypothetical landscapes using a combination of deterministic and probabilistic 'rules' for plant placement coupled with environmental parameters such as topography, simulating the pollen assemblage produced by each, and comparing them statistically with a sedimentary pollen signal to identify possible reconstructions. The method expressly aims to find multiple possible reconstructions, and also gives some insight into the spatial aspects of the vegetation being reconstructed in addition to its composition. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue, including one by Bunting on examines recent work that best interpret pollen signal from the archive, and another by Mitchell and colleagues on groups of organism that live in wetland such as testate amoeba.

Palaeoenvironmental and radiocarbon data are presented from an infilled freshwater basin (Lambwath Mere) in Holderness, East Yorkshire (UK). The site contains a rare and detailed c. 4000 cal. yr mid-Holocene pollen record for the floating-leaved aquatic plant Trapa natans (L.) (water chestnut). Competing hypotheses (natural and anthropogenic) to explain the earlier presence of this 'exotic' species in Holderness are evaluated. Maximum Trapa frequencies date to the interval 6200–4200 cal. BP and are shown to occur during shallow open water conditions just prior to overgrowth of the basin by semi-terrestrial vegetation communities. There is no clear palynological or archaeological evidence from the site to suggest settlement or significant human activity around the mere during this episode. It appears more likely that the occurrence of water chestnut at this site can be explained through natural factors (a combination of a favourable climate and the availability of a suitable habitat) rather than as a prehistoric human introduction. [ABSTRACT FROM AUTHOR]

• Paired soil and moss samples captured similar levels of variability in the pollen assemblages retained. • Mosses provide a more accurate representation of the contemporary vegetation composition. • Adjacent sites with similar vegetation may show differences in the pollen-vegetation relationships. • Surface pollen samples from bamboo forests are likely to be influenced by the surrounding communities. This study investigated the pollen spectra from 46 pairs of soil and moss samples (pairs collected within a 1 m2 squared area). The samples were collected from six common subtropical vegetation communities in the Meiling Mountains, southeast China, with the vegetation proportions recorded at the collection point. Principal Component Analysis (PCA) was used to investigate the separation of the paired assemblages and to determine whether different plant communities produced distinctive pollen spectra. Paired soil and moss samples captured similar levels of variability in the pollen assemblages retained, but there are systematic differences in the mean values of key groups of taxa. Monte Carlo sampling shows that, in most cases, intra-pair differences are greater than could be explained by counting uncertainty alone. In this study, discriminant analysis of surface soil and moss found that 91.3% of the soil samples and 87% of the moss samples were correctly classified into their vegetation communities. However, the detailed pollen assemblages suggest that mosses provide a more accurate representation of the contemporary vegetation composition than soils. Pollen assemblages from moss samples seem to record local vegetation more accurately than those from soil samples. Higher vegetation diversity within an arboreal forest community leads to greater differences between moss-soil pairs. In bamboo forests, pollen assemblages in soils and moss show strong influence from the surrounding communities, which makes it hard to identify bamboo forest via surface sample pollen assemblages alone. [ABSTRACT FROM AUTHOR]

This paper presents the results of airborne pollen and spore trapping in Nanjing city, eastern China, using a Burkard pollen trap during two consecutive years (2013–2014). A total of 103 pollen and spore taxa were identified. Two concentration peaks are observed in the annual cycle, a spring peak dominated by arboreal pollen types (Morus, Cupressaceae, Pinus, Pterocarya, and Quercus) and a fall peak dominated by upland herbs (Compositae, Poaceae, Humulus, and Cruciferae). Wetland herbs and ferns dominate summer assemblages and winter assemblages are characterized by sporadic records of Artemisia, Chenopodiaceae, and Pinus. Strong year‐to‐year differences in measured pollen concentration are seen, probably in response to interyear differences in weather. Compared to long‐term means, 2013 was comparatively hot and dry and 2014 had a higher than average number of rain days during the flowering periods. Rising temperatures in early spring are connected with the timing of flowering and therefore pollen release, while rainfall during the flowering period appeared to remove pollen from the air, leading to lower recorded pollen concentration values. Four taxa, Cupressaceae, Quercus, Pinus, and Humulus, were considered in more detail. Each has a different pattern of variation in pollen concentration between the studied years. Cross correlation between pollen concentration and daily temperature, relative humidity, and precipitation at lags from 0 to −30 days also showed different responses for each taxon, suggesting that pollen signal responses to weather conditions have to be considered at a taxon level rather than at the assemblage level. Key Points: Two pollen concentration peaks were recorded, a spring peak dominated by arboreal pollen types and a fall peak dominated by upland herbsPollen concentration values were markedly different between the two years, probably reflecting differences in weatherPollen signal responses to weather conditions have to be considered at a taxon level rather than at the assemblage level [ABSTRACT FROM AUTHOR]

Montane ecotones such as the forest-steppe transition are highly sensitive and responsive to climate change. Thus, reconstructing changing ecotone position is a valuable tool for reconstructing past climate change in mountainous regions, although identifying this from the pollen record can be challenging. Mathematical models of the pollen-vegetation relationships can be used to explore the detectability thresholds for ecotones, and the reliability of these reconstructions depends considerably on the suitability of the pollen dispersal and deposition models used. In this study, we compared pollen assemblages collected across the forest-steppe ecotone in the Tian Shan Mountains with predictions of a selection of pollen dispersal and deposition models as a test of whether they are appropriate to be used in mountainous regions. The modern pollen spectra show clear association with the local vegetation communities. Picea pollen dominate in the samples from the spruce forest, remain relatively high within hundreds of meters from the forest edge, and drop to background level (0.8% on average) by 1 km away from the forest edge. Both the log 2 (z) model and the z −1 model (z = distance from forest edge) performed well at simulating these changes, suggesting that although they do not incorporate topographic variations, these models can still be used with confidence to explore and to reconstruct past changes in the position of this ecotone at least over the Holocene. • The modern pollen spectra provided clear representation of the local vegetation communities. • A clear "forest edge effect" zone is documented in the northern slope of the Tien Shan Mountains. • Both logarithm model and inverse distance model performed well at capturing main patterns of pollen deposition across forest boundaries. • Pollen records from small sites could be used to detect treeline position as a palaeoclimatic marker. [ABSTRACT FROM AUTHOR]

Abstract: Investigations of pollen production, modern pollen–vegetation relationships and pollen‐stratigraphic changes have been undertaken from three woodlands under coppice management to establish the impact that woodland management techniques (the periodic cutting of broadleaved trees and shrubs for wood and fodder) have on pollen representation. The number of inflorescences (catkins/flowers) produced over the length of a coppice rotation has been quantified for three species; Corylus avellana, Alnus glutinosa and Tilia cordata. For C. avellana the number inflorescences produced is significantly higher in the early years after coppicing. For A. glutinosa and particularly T. cordata flowering is suppressed after coppicing and only recovers slowly. In the later years the number of inflorescences produced by all three species is related to the height of the regrowths and therefore competition for light. However, the number of pollen grains produced per inflorescence appears not to be related to age in the coppice rotation. The modern pollen rain within the coppiced woodlands largely reflects differences in the vegetation of the coppiced areas rather than variations resulting from their age in the coppice rotation. High resolution pollen-stratigraphic records from small ponds record long-term vegetation trends, while the coppicing of adjacent areas is difficult to detect. Nevertheless, the results from these studies are broadly consistent with the pollen production investigations and together show that coppicing results in a shift in pollen production from canopy to under-storey species and may render some taxa (notably T. cordata) palynologically invisible. Model simulations, with corrections for differences in pollen production through the coppice rotation, have been produced for three types of basin; small ponds/hollows, small lakes and wet woodlands with A. glutinosa. These explore the impact of changes in the intensity and scale of coppicing on pollen assemblages from mixed deciduous woodland. The simulated assemblages are compared with mid–late Holocene pollen records from temperate regions of north-west Europe where archaeological/historical evidence suggests that woodland management is likely to have been practiced. Some changes in the representation of trees and shrubs recorded in pollen diagrams from small hollows within wooded landscapes in southern Scandinavia and from A. glutinosa woodland in southern England are consistent with woodlands being managed. Notably pollen diagrams from the northern Alpine Forelands and East Anglia are compatible with long-standing ideas that woodland was managed on a landscape scale during the Neolithic. Further studies are required to determine whether a number of related woodland management practices produce distinct pollen signatures and the impact of these processes on a wider range of species. [Copyright &y& Elsevier]

This paper examines the degree to which tree-associated Coleoptera (beetles) and pollen could be used to predict the degree of 'openness' in woodland. The results from two modern insect and pollen analogue studies from ponds at Dunham Massey, Cheshire and Epping Forest, Greater London are presented. We explore the reliability of modern pollen rain and sub-fossil beetle assemblages to represent varying degrees of canopy cover for up to 1000 m from a sampling site. Modern woodland canopy structure around the study sites has been assessed using GIS-based mapping at increasing radial distances as an independent check on the modern insect and pollen data sets. These preliminary results suggest that it is possible to use tree-associated Coleoptera to assess the degree of local vegetation openness. In addition, it appears that insect remains may indicate the relative intensity of land use by grazing animals. Our results also suggest most insects are collected from within a 100-200 m radius of the sampling site. The pollen results suggest that local vegetation and density of woodland in the immediate area of the sampling site can have a strong role in determining the pollen signal. [ABSTRACT FROM AUTHOR]

Thick deposits of peat derived from fen environments accumulated in the coastal lowland areas adjacent to the North Sea during the middle and late Holocene. These sediments are frequently used in pollen-based reconstructions of in situ and more distant vegetation. However, discriminating between wetland and dry land originating pollen signals, and between the potential fen communities present in the wetland, is complex. In this study, a suite of analytical approaches are used to explore the pollen signal of modern fen communities and compare them against Holocene pollen assemblages. At two sites in eastern England, Woodwalton Fen and Upton Broad, vegetation composition was recorded around a series of moss polster sampling points. The communities investigated included herbaceous fen communities under different cutting regimes, a grazed area, glades, and woodland with canopies dominated by Alnus glutinosa and Betula . Cluster analysis is used to provide an overview of, and compare the structure within, the datasets consisting of the vegetation, the vegetation converted to palynological equivalents, and the pollen data. It is demonstrated that any loss of taxonomic precision in pollen identifications does not pose particular problems when attempting to identify fen communities, including tall-herbaceous vegetation, in the pollen record. Indices of Association imply pollen presence can be interpreted as indicating the local presence for some taxa, though few of these are confined to a particular community. Herbaceous fen vegetation subject to different management regimes are, however, shown to produce distinctive pollen signatures. Middle and late Holocene pollen assemblages from eastern (Fenland) and southern (Romney Marsh) England, interpreted as derived from fen vegetation, are compared against the modern pollen dataset using ordination. Most of the fossil samples plot out within or adjacent to the groupings produced by the modern samples in the ordinations. While these investigations demonstrate that modern pollen work can help improve the interpretation of Holocene assemblages they also call attention to a number of limitations including the restricted range of communities from which modern samples are currently available and the potential for non-analogous modern vegetation. The paper concludes with ideas to aid the interpretation of pollen data collected from fen peats and suggestions for future work. [ABSTRACT FROM AUTHOR]

The margins of mainland Europe, and especially those areas coming under the influence of North Atlantic weather systems, are ideally placed to record changing palaeoclimates. Cores from an infilled lake basin at Crudale Meadow in Mainland, Orkney, revealed basal deposits of calcareous mud (‘marl’) beneath sedge peat. Stable isotope, palynological and molluscan analyses allowed the establishment of palaeoenvironmental changes through the Devensian Lateglacial and the early Holocene. The δ 18 O marl record exhibited the existence of possibly four climatic oscillations in the Lateglacial (one of which, within event cf. GI-1c, is not often commented upon), as well as the Preboreal Oscillation and other Holocene perturbations. The cold episodes succeeding the Preboreal Oscillation were demarcated conservatively and one of these (event C5, ∼11.0 ka) may have previously been unremarked, while the putative 9.3 and 8.2 ka events seem not to produce corresponding palynologically visible floristic changes. The events at Crudale Meadow are consistent with those recorded at other sites from Britain, Ireland and elsewhere, and can be correlated with isotopic changes shown by the Greenland ice cores. The multi-proxy approach enriches the environmental reconstructions from the site, although the synchronicity of the response of the various proxies is sometimes equivocal, depending upon the time period concerned, taphonomy, and the nature of the deposits. The site may contain the most northerly Lateglacial isotope record from northwest Europe, and it has yielded one of the best archives for the demonstration of abrupt early Holocene events within Britain. [ABSTRACT FROM AUTHOR]

A multi-disciplinary study assessing the evidence for agriculture in Neolithic Ireland is presented, examining the timing, extent and nature of settlement and farming. Bayesian analyses of palaeoenvironmental and archaeological 14 C data have allowed us to re-examine evidential strands within a strong chronological framework. While the nature and timing of the very beginning of the Neolithic in Ireland is still debated, our results – based on new Bayesian chronologies of plant macro-remains – are consistent with a rapid and abrupt transition to agriculture from c. 3750 cal BC, though there are hints of earlier Neolithic presence at a number of sites. We have emphatically confirmed the start of extensive Neolithic settlement in Ireland with the existence of a distinct ‘house horizon’, dating to 3720–3620 cal BC , lasting for up to a century. Cereals were being consumed at many sites during this period, with emmer wheat dominant, but also barley (naked and hulled), as well as occasional evidence for einkorn wheat, naked wheat and flax. The earliest farmers in Ireland, like farmers elsewhere across NW Europe, were not engaged in shifting cultivation, but practised longer-term fixed-plot agriculture. The association between early agriculture and the Elm Decline seen in many pollen diagrams shows that this latter event was not synchronous across all sites investigated, starting earlier in the north compared with the west, but that there is a strong coincidence with early agriculture at many sites. After this early boom, there are changes in the nature of settlement records; aside from passage tombs, the evidence for activity between 3400 and 3100 cal BC is limited. From 3400 cal BC, we see a decrease in the frequency of cereal evidence and an increase in some wild resources (e.g. fruits, but not nuts, in the records), alongside evidence for re-afforestation in pollen diagrams (3500–3000 cal BC). Changes occur at a time of worsening climatic conditions, as shown in Irish bog oak and reconstructed bog surface wetness records, although the links between the various records, and assessment of causes and effects, will require further investigation and may prove complex. This period seems to have been one of environmental, landscape, settlement and economic change. The later 4th millennium BC emerges as a period that would benefit from focused research attention, particularly as the observed changes in Ireland seem to have parallels in Britain and further afield. [ABSTRACT FROM AUTHOR]