The vegetation of Europe has undergone substantial changes during the course of the Holocene epoch, resulting from range expansion of plants following climate amelioration, competition between taxa and disturbance through anthropogenic activities. Much of the detail of this pattern is understood from decades of pollen analytical work across Europe, and this understanding has been used to address questions relating to vegetation-climate feedback, biogeography and human impact. Recent advances in modelling the relationship between pollen and vegetation now make it possible to transform pollen proportions into estimates of vegetation cover at both regional and local spatial scales, using the Landscape Reconstruction Algorithm (LRA), i.e. the REVEALS (Regional Estimates of VEgetation Abundance from Large Sites) and the LOVE (LOcal VEgetation) models. This paper presents the compilation and analysis of 73 pollen stratigraphies from the British Isles, to assess the application of the LRA and describe the pattern of landscape/woodland openness (i.e. the cover of low herb and bushy vegetation) through the Holocene. The results show that multiple small sites can be used as an effective replacement for a single large site for the reconstruction of regional vegetation cover. The REVEALS vegetation estimates imply that the British Isles had a greater degree of landscape/woodland openness at the regional scale than areas on the European mainland. There is considerable spatial bias in the British Isles dataset towards wetland areas and uplands, which may explain higher estimates of landscape openness compared with Europe. Where multiple estimates of regional vegetation are available from within the same region inter-regional differences are greater than intra-regional differences, supporting the use of the REVEALS model to the estimation of regional vegetation from pollen data. © 2013 Elsevier Ltd.

This paper describes a research project that aimed to translate complex spatial and scientific data about coastal change into accessible digital formats for general audiences. The project used fine-scale remote sensing techniques including airborne and terrestrial laser scanning to produce spatially accurate and realistic 3D digital visualisations of projected sea level rise at Cotehele Quay, a site on the River Tamar in Cornwall owned and managed by the National Trust. Area residents and stakeholders were involved in a series of focus groups which provided guidance on the integration of the spatial models into a short film. The paper focuses on how the participatory, iterative process adopted in the project shaped the content and design of the film. The paper concludes with a discussion of how this process enhanced the viability of the film as a communication tool for use in wider engagement activities.

Keywords: : Terrestrial laser scanning , heritage , sea-level rise , community engagement , multi-media

Palaeoscientists of necessity deal with time as a fundamental part of the research process and have developed understandings within the discipline of how to deal with a range of timescales from the deep time of Archaean geology to recent time, that is the last few centuries. Time has however largely been seen as providing a chronology, the ability to place events in sequence and through the implementation of various dating techniques to relate these sequences across space, providing fundamental information toward understanding cause and effect within the Earth system. Variability in the units of time, the differences between radiometric and sidereal or calendrical years is accounted for and not deemed significant. When dealing with other disciplines, either through research into the relationship of past societies to climate change, or when contributing to the concerns over future directions of climate problems arise in attempting to communicate the nature of timescales. The real issue is to reinforce the idea of change as a basic quality of the climate system, something that can occur very rapidly. It is open to question whether a concentration on timescales of climate change is proving a distraction in terms of communication from the most important issue. Change is a fundamental property of the global climate system, and from our paleoscience knowledge it is clear that change will continue into the future and could well be very rapid. © 2012 John Wiley & Sons, Ltd.

At the millennial scale bog surface wetness (BSW) records show a clear Holocene climate event stratigraphy, with major phases comparable with other regional climate proxies such as chironomid inferred temperature records. Moving towards the centennial scale, however, and towards the limits of chronological certainty within the records, regional differences are apparent which likely reflect the more heterogeneous precipitation patterns which occur on shorter timescales. The BSW data presented in this paper are reconstructed from testate amoebae assemblages from central Ireland and are compared with other regional records. The results suggest that this region is in phase with the North of Ireland in terms of timings and durations of climate change, but the comparisons are less clear with a stacked and tuned record from Northern Britain that shows an apparent offset compared to the Irish records. This may reflect variations in past regional precipitation or be a function of the tuning and stacking process. The broad phases of comparison between the Irish records, and the extension of the central Irish record back to 6000 cal BP, allow comparisons with low frequency temperature reconstructions from chironomids, which also show a broad level of correlation, with cooler temperatures relating to wetter BSW at centennial to millennial timescales. © 2011 Elsevier Ltd and INQUA.

Few studies currently exist that aim to validate a proxy chironomid-temperature reconstruction with instrumental temperature measurements. We used a reconstruction from a chironomid percentage abundance data set to produce quantitative summer temperature estimates since AD 1650 for NW Iceland through a transfer function approach, and validated the record against instrumental temperature measurements from Stykkishólmur in western Iceland. The core was dated through Pb-210, Cs-137 and tephra analyses (Hekla 1693) which produced a well-constrained dating model across the whole study period. Little catchment disturbance, as shown through geochemical (Itrax) and loss-on-ignition data, throughout the period further reinforce the premise that the chironomids were responding to temperature and not other catchment or within-lake variables. Particularly cold phases were identified between AD 1683-1710, AD 1765-1780 and AD 1890-1917, with relative drops in summer temperatures in the order of 1.5-2°C. The timing of these cold phases agree well with other evidence of cooler temperatures, notably increased extent of Little Ice Age (LIA) glaciers. Our evidence suggests that the magnitude of summer temperature cooling (1.5-2°C) was enough to force LIA Icelandic glaciers into their maximum Holocene extent, which is in accordance with previous modelling experiments for an Icelandic ice cap (Langjökull). © 2010 University of Washington.

The introductory comments to the Special Issue: IPCC and palaeoclimate, concentrate on considering how the role of palaeoclimate research has evolved over the two decades of IPCC Reports. There have been significant changes in the nature and prominence of palaeoclimate research examined with the Fourth Assessment Report (FAR) representing a major step in giving such research a high profile. The implications of this for future palaeoclimate research are briefly reviewed. © 2010 John Wiley & Sons, Ltd.

Early-Holocene warming in Iceland caused rapid glacial ice melt which led to exposed landscapes on which soils developed and floras quickly established. Our chironomid-based records from northern Iceland suggest temperatures were up to 2-2.5°C warmer than present throughout the first two millennia post deglaciation (~10 500 to 8500 cal. BP) while sedimentary and isotopic data indicate the development of soils within the local environment throughout this period before catchment conditions started to stabilise around 8400 cal. BP. The warming trend over this period was not uniform however, but punctuated by a series of relatively short-lived climatic events. Specifically inwash events are suggested by the δ13Corganic, %TOC and C/N data around 9600 cal. BP and 8250 cal. BP and are seen at two independent sites. There is also evidence from the δ18Ocarbonate and δ13Ccarbonate records which suggests that progressive evaporation of the study lakes occurred from ~8200 cal. BP, the timing of which accords well with other isotopic records of drier conditions from around the North Atlantic. © the Author(s), 2010.

Pictorial, and increasingly photo-realistic, visualisation of past landscapes is underpinned by reconstructions of the past environment themselves effected through palaeoecological methods. The role played by such visualisations has traditionally been that of final-statement, or end-product, intended to convey a synthesis of the interpretation for general consumption, geared around the deceptively straightforward question '. what did the landscape look like in the past?'. This paper seeks to provide a critical appraisal of the production of such visualisations, through exploration of the nature, spatial scale and interpretative framework of the palaeoecological datasets that underpin them. It is argued that a more sophisticated approach to the spatial interpretation of data is needed, through different approaches to spatial sampling, to facilitate what might be considered complete, and more importantly plausible, visualisations of the past. These visualisations should be considered partial at best, and certainly not full representations of the experiences of communities and individuals that engaged with them. Finally, it is argued that the role of visualisation of past landscapes should move beyond the presentation of interpretations as an end-product of research. Rather, they should form part of the interpretative framework of research that by its very nature needs to be interdisciplinary from start to finish. © 2009 Elsevier Ltd and INQUA.

A suite of surface sediment samples from three Icelandic lakes was analysed for subfossil chironomid head capsules, and a quantitative July air temperature inference model was applied to the data to investigate whether there was significant variability among samples taken from a lake. Ordination and simple regression methods were used to analyse the relationships between environmental and sedimentological variables and the chironomid assemblages and inferred temperature data. Substrate was the most important influence on the chironomid assemblages and inferred temperatures, while water depth at the sampling location had no relationship with the chironomid-inferred temperatures. Within-lake variability of the chironomid assemblages and their inferred temperatures, however, were not significant statistically, suggesting that in lakes of western and northwest Iceland within-lake sampling location has no effect on the data obtained, and therefore on training set samples. © 2008 Springer Science+Business Media B.V.

Reconstructing climate change quantitatively over millennial timescales is crucial for understanding the processes that affect the climate system. One of the best methods for producing high resolution, low error, quantitative summer air temperature reconstructions is through chironomid analyses. We analysed over 50 lakes from NW and W Iceland covering a range of environmental gradients in order to test whether the distribution of the Icelandic chironomid fauna was driven by summer temperature, or whether other environmental factors were more dominant. A range of analyses showed the main environmental controls on chironomid communities to be substrate (identified through loss-on-ignition and carbon content) and mean July air temperature, although other factors such as lake depth and lake area were also important. The nature of the Icelandic landscape, with numerous volcanic centres (many of which are covered by ice caps) that produce large quantities of ash, means that relative lake carbon content and summer air temperature do not co-vary, as they often do in other chironomid datasets within the Arctic as well as more temperate environments. As the chironomid-environment relationships are thus different in Iceland compared to other chironomid training sets, we suggest that using an Icelandic model is most appropriate for reconstructing past environmental change from fossil Icelandic datasets. Analogue matching of Icelandic fossil chironomid datasets with the Icelandic training set and another European chironomid training set support this assertion. Analyses of a range of chironomid-inferred temperature transfer functions suggest the best to be a two component WA-PLS model with r 2jack = 0.66 and RMSEP = 1.095°C. Using this model, chironomid-inferred temperature reconstructions of early Holocene Icelandic sequences show the magnitude of temperature change compared to contemporary temperatures to be similar to other NW European chironomid sequences, suggesting that the predictive power of the model is good. © 2007 Springer Science+Business Media B.V.

As with many terrestrial areas, the British Quaternary sequence is characterised by incomplete, fragmentary records, whose correlation is based on stratigraphic or biostratigraphic techniques due to the lack of radiometric ages beyond the ∼40 kyr limit of 14C dating. Speleothems (secondary cave calcite deposits) offer a significant advantage over many sources of palaeoenvironmental information; they can be dated to a high precision and accuracy by uranium-thorium (238U-230Th) thermal ionisation and inductively coupled plasma (ICP) mass spectrometry in the time period back to 500 kyr. They may also contain sufficient well-preserved pollen representative of contemporary vegetation above the cave to allow palaeoenvironmental reconstruction. This study adopts the novel approach of combining pollen and thermal ionisation mass spectrometric (TIMS) U-Th dating of British speleothems to produce well-constrained palaeoenvironmental records. We report for the first time precisely dated records of pollen assemblages from speleothems suggesting the presence of thermophilous arboreal species in phases previously considered to have been consistently cool or cold and devoid of trees. Copyright © 2007 John Wiley & Sons, Ltd.

Peat bogs are highly effective archives for the preservation and detection of cryptotephra but the conventional methods used to detect these hidden, diminutive layers are destructive and can be time consuming. We briefly review methods that have been used for cryptotephra detection and evaluate the potential of a range of alternative reconnaissance methods, both non-destructive and destructive, to provide for more rapid examination of continuous cryptotephra content in peat cores. The techniques evaluated-magnetic susceptibility (MS), spectrophotometry, and X-ray fluorescence-are used to pick out compositional contrasts between tephra deposits and peat. Measurements of organic content are also evaluated as a potential guide to tephra content based on an inverse relationship. Although we find limitations to each method, particularly where deployed at the distal-most end of tephra dispersal, there is potential for all methods to be used in the detection of cryptotephra where time or material is limited. These methods can also provide additional sedimentological and stratigraphic information for studies of peat cores. However, where a reliable cryptotephra profile is required, we conclude that there is no quick or easy substitute for the conventional extraction-microscopy method. © 2006 Elsevier Ltd and INQUA.

The landscapes of the extreme western fringe of the European seaboard provide significant challenges to the reconstruction of prehistoric landscapes. The landscapes that exist today often bear little resemblance to those that existed in the middle Holocene owing to a combination of climatic and human influences on the landscape, and there are few surviving landscapes which offer an analogous vegetation situation. The coast of Co. Mayo in Ireland provides perhaps one of the biggest challenges in this regard, being now virtually treeless and covered with extensive tracts of ombrotrophic peat. Palaeoecological data sets indicate extensive woodland in the past in these areas, and the archaeological record shows that the region supported Neolithic populations practising early forms of agriculture. Landscape reconstruction using models that relate pollen dispersal to vegetation communities offers a potential stochastic insight into the nature of former landscapes. The results presented here from a modelling approach to reconstructing earlier prehistoric landscapes clearly demonstrate likely spatial vegetation patterning which could produce pollen assemblages comparable to those in the sub-fossil record. Areas such as Achill Island would have had extensive woodland cover dominated by taxa such as pine, oak and elm, a landscape substantially different from that which exists today. It is argued that at the onset of clearance during the Neolithic the area would have been significantly more attractive to agriculture than it is today. © 2006 Elsevier B.V. All rights reserved.

The value of testate amoebae in the reconstruction of changes in surface wetness from ombrotrophic mires is well known, but the potential value of such records in specifically archaeological investigations has not yet been investigated. This note describes the analysis of testate amoebae for a sediment sequence from the multi-period wetland archaeological site of Derryville, Co. Tipperary, Ireland. The reconstructed watertable is presented and plotted against the range of dates from excavated archaeological features in the wetland area. The data demonstrate a clear association between periods of low watertable and increased anthropogenic activity as reflected by site construction. The value of testate amoebae in future integrated archaeological investigations of wetland systems is discussed. © 2005 Elsevier Ltd. All rights reserved.

Black Ridge Brook is an upland peat site in a high rainfall area of SW England. Pollen evidence has shown that it was once wooded, with Betula and Corylus dominant, before periods of change to more open ground and the spread of mire vegetation. Previous palaeoecological work at the site inferred a history of burning based on microscopic charcoal levels, with the burning periods reducing Betula cover. These changes occurred between 9000 and 6300 BP (radiocarbon years) during the Mesolithic archaeological period, and have been linked to the impacts of hunter-gatherers using fire, as suggested elsewhere in upland Britain. In this paper, hypotheses of deliberate burning, grazing and the reasons for using fire are tested using non-pollen palynomorphs in addition to the microcharcoal and pollen data. While indicators of dung are present, the frequencies are low, and not always in the levels expected on the basis of vegetation change, although some correlation of disturbance indicators is seen in the earlier Holocene before woodland cover reached a maximum. There is evidence for increased and sustained growth of Corylus following increases in inferred fire frequency. Statistical analysis of the combined data set shows the association of some non-pollen types with specific stages in the development, and then recession, of woodland. Other types show the presence of on-site burning or host plants, and help distinguish between local and regional vegetation changes. The nature of the depositional environment is both shown by, but also affects, the non-pollen microfossil record. © 2006 Elsevier B.V. All rights reserved.

In the Late Preboreal and Early Boreal Chronozones dwarf-shrub heath and shrub heath, followed by juniper and mountain birch copses, replaced snow beds and fellfield vegetation characteristic of the Lateglacial/Early Preboreal newly deglaciated landscape of Iceland. During the Late Boreal and Early Atlantic Chronozones birch woodland established itself in the more favourable places, especially fjord lowlands and inland valleys. The development of birch woodland suffered a setback due to a transient climatic oscillation some 7500 14C years ago, but recovered again relatively quickly and more than 6000 14C years ago birch woodland covered the lowland areas both in northern and southern Iceland. At that time it reached its highest altitude, at least in northern Iceland. During the Late Atlantic and Subboreal Chronozones the birch woodland showed a retrogressive succession towards a more open landscape with expanding mires and heaths. There is some conflict between the evidence from pollen percentages, which indicate that the woodland regenerated several times during the latter half of the Holocene, and pollen influx values which reflect no such regeneration of the woodland. New habitats were created for birch after a period of cool climate and instability during the Early Subatlantic Chronozone as fresh screes and sandur plains became vegetated, at least partly, by woodland. This development was halted at the beginning of the Norse settlement, which resulted in further opening of the woodland. The birch woodland closest to the farms in the lowland of Iceland was cut and utilized for timber and fuel. Grazing of domestic animals opened the landscape still further and the previous woodland never re-established itself. This happened within only half a century from the arrival of the first settlers. During the ensuing 1100 years of human influence the sub-alpine birch woodland has been so intensively utilized that only in fenced, protected areas and at the most inaccessible and remote places has birch survived. The shrub and dwarf-shrub heaths, widespread mires, fell fields, and hay fields so characteristic for the Icelandic landscape at present thus developed as a relatively recent phenomenon in the form in which they appear today. A number of areas are identified for future research: elucidating the origins of the Icelandic flora, deriving palaeoclimatic data from the vegetation record, correlating terrestrial with marine and ice core records and expanding our understanding of the human impact on vegetation. © 2005 Elsevier B.V. All rights reserved.

Multiproxy analyses comprising peat stratigraphy, testate amoebae, pollen and humification analyses from four profiles across a complex raised mire system at Derryville Bog, Co. Tipperary, Ireland are used to demonstrate the surface wetness changes covering the period cal. BC 1500 to cal AD 1000, with special reference to a series of bog bursts identified within the stratigraphic record. Comparison of the proxies reveals varying levels and forms of response to the bursts depending on the size of the burst and the relative location of the site, and reinforces the necessity for such detailed studies in reconstructing the full palaeohydrological history of large and complex sites. Because of the heavily cut-over nature of the bog the availability of extensive sections from which peat-stratigraphic data can be obtained also reinforces the inherent weakness in relying on coring data when trying to understand the complex structure of such large systems. © 2005 Edward Arnold (Publishers) Ltd.

A high-resolution pollen record for the Holocene has been obtained from Derragh Bog, a small raised mire located on a peninsula in Lough Kinale-Derragh Lough, in Central Ireland as part of the Discovery Programme (Ireland) Lake Settlements Project. The data are compared with two lower resolution diagrams, one obtained from Derragh Lough and one from adjacent to a crannog in Lough Kinale. The general trends of vegetation change are similar and indicate that landscape-scale clearance did not occur until the Medieval period (ca. a.d. 800-900). There are, however, significant differences between the diagrams due primarily to core location and taphonomy, including pollen source area. Only the pollen profile from Derragh Bog reveals an unusually well represented multi-phase primary decline in Ulmus ca. 3500-3100 b.c. (4800-475014C b.p.) which is associated with the first arable farming in the area. The pollen diagram indicates a rapid, and almost complete, clearance of a stand of Ulmus with some Quercus on the Derragh peninsula, arable cultivation in the clearing and then abandonment by mobile/shifting late Neolithic farmers. Subsequently there are a number of clearance phases which allow the colonisation of the area by Fraxinus and are probably associated with pastoral activity. The pollen sequence from adjacent to a crannog in Lough Kinale shows clear evidence of the construction and use of the crannog for the storage of crops (Hordeum and Avena) whereas the Derragh Bog diagram and the diagram from Derragh Lough reflect the growth of the mire. This study reveals that in this landscape the record from a small mire shows changes in prehistoric vegetation caused by human agriculture that are not detectable in the lake sequences. Although in part this is due to the higher temporal resolution and more consistent and complete chronology for the mire, the most important factor is the closer proximity of the raised mire sequence to the dry land. However, the pollen sequence from adjacent to a crannog does provide detailed evidence of the construction and function of the site. It is concluded that in order to ascertain a complete picture of vegetation changes in a lowland shallow lake-dominated landscape, cores from both the lake and surrounding small mires should be analysed. © Springer-Verlag 2005.

We studied the late Holocene foreland and adjacent unglaciated terrain of a small cirque glacier system in north Iceland to explore the relationship between soil/ surface age, vegetation and soil evolution, and C isotope signatures of respired CO2 Field-based sampling of respired CO2 from vegetation/soil monoliths across the chronosequence was used as the basis for an analysis of the 12C:13C:14C atom ratios of CO2 using Isotope Ratio Mass Spectrometry (IRMS) and Accelerator Mass Spectrometry (AMS). Residual soil organic matter (SOM) fractions (humic and humin) were also 14C-dated from each of the surfaces, vegetation described, and soil C and N contents analyzed. Our major conclusions are (1) that ecosystem respiration in this mid-alpine environment is strongly dominated by "young" C and is not related to the 14C age of residual SOM fractions; (2) δ13C values of respired CO2, by contrast, do vary both with age of surface and with absolute respiration rate, but there is no clear indication of any effects mediated by plant species and functional type and/or the degree of reworking of SOM by decomposer organisms; and (3) the 14C dating of residual SOM fractions, together with the soil profile characteristics (including tephra deposits) and vegetation cover, both suggest some radical disturbance in soil development and SOM formation at Site 1 (the oldest surface studied here), and no clear signs of classical succession when comparing Sites 1 to 3. Finally, in the light of these observations, the familiar concept of chronosequences, and the predictable processes of ecosystem development that they often imply, are challenged in a mid-alpine tundra setting where recent climate change and anthropogenic influences (e.g. grazing pressure) are superimposed upon time as an ecological factor.

River-channel and colluvial deposits, near Marsworth, Buckinghamshire, record a temperate-periglacial-temperate sequence during the late Middle Pleistocene. The deposits of a lower channel contain tufa clasts bearing leaf impressions that include Acer sp. and Sorbus aucuparia and containing temperate arboreal pollen attributed to ash-dominated woodland. The tufa probably formed at the mouth of a limestone spring before being redeposited in a small river whose deposits contain plant remains, Mollusca, Coleoptera, Ostracoda and vertebrate bones of temperate affinities. The sediments, sedimentary structures and limited biological remains above the Lower Channel deposits indicate that fluvial deposition preceded climatic cooling into periglacial conditions. Fluvial deposition recurred during a later temperate episode, as shown by the mammalian bone assemblage in stratigraphically higher channel deposits. The Upper Channel deposits are confidently attributed to Oxygen Isotope Sub-stage 5e (Ipswichian) on the basis of their vertebrate remains. However, the age of the Lower Channel deposits is less clear. The mammalian and coleopteran remains in the Lower Channel strongly suggest correlation with oxygen isotope stage 7 on the basis of their similarities to other sites whose stratigraphy is better known and the clear difference of the Lower Channel assemblage from well-established faunas of Ipswichian or any other age. By contrast, U-Th dating of the tufa clasts suggests an age post 160 ka BP, while Aile/Ile ratios on Mollusca point to an Ipswichian age and younger. Four ways of interpreting this age discrepancy are considered, the preferred one correlating the Lower Channel deposits with Oxygen Isotope Stage 7. © 2001 Elsevier Science Ltd. All rights reserved.

Paleohydrological changes during the late Holocene are inferred from humification testate amoebae and pollen evidence from three blanket peat profiles in northwest Scotland. Replicate peat humification records from the Traligill basin share the same patterns of change for a 600-yr period of overlap between 1800 and 2400 cal yr B.P. The shared patterns inferred from samples with a resolution of 5-13 yr represent basinwide hydrological changes. In a nearby but hydrologically separate area with caves beneath peat the luminescence emission wavelength measured in two speleothem samples correlated with the humification record in the overlying peat. This correlation implies that speleothem luminescence emission wavelength depends primarily on decay rates in the soils from which drip waters are derived as long as there is no major change in soil or vegetation. The peat and speleothem records from the cave site further correlate with the peat records from the Traligill basin. Taken together the records thus represent a regional climatic signal. Peaks in surface wetness replicated in two or more records occur at ca. 2300 2090 2030 1820 1600 and 1440 cal yr B.P. Further peaks occur at 800 570 and 115 cal yr B.P. in the humification and stalagmite records that extend to the present day. Correlative changes have been observed not only in other peat records from Scotland but also in ice accumulation at GISP2. These further correlations imply that precipitation regimes in Scotland and Greenland were in phase during the late Holocene. © 2001 University of Washington.

For paleoclimatic reconstructions based on vegetation history in Iceland, the upper limit of tree or shrub birch growth has been proposed as an indicator of summer temperature. Plant macrofossil and pollen analyses of a series of sections and cores from Vesturárdalur on Tröllaskagi show that Betula pubescens grew up to an altitude between 450 and 500 m a.s.l. during optimum conditions in the Holocene. The birch pollen and macrofossil record of core Vesturárdalur 2 at ca. 450 m a.s.l. which covers the time from ca. 9200 BP to present, thus represents the first continuous high-resolution reconstruction of the variations of Betula pubescens at the ecological upper limit of tree or shrub birch in northern Iceland. Between ca. 6700 and ca. 6000 BP, a distinct maximum in the influx of Betula pubescens pollen at this site indicates a high position of the shrub line. This can be distinguished from a low influx of tree or shrub birch pollen from ca. 6000 to ca. 5600 BP, and a very pronounced minimum of Betula pubescens in the pollen record around ca. 3300 BP. The inferred depressions of the shrub line can be correlated with evidence for glacier advances and increased slope activity in northern Iceland.

Assessment of the degree of decay of peat (humification) in ombrotrophic mires has become a standard technique for palaeoclimatic reconstruction, based on the finding that decay is primarily determined by surface wetness and temperature at the time of peat deposition. Determination of humification is undertaken by colorimetric measurement of an alkali extract of the peat at 540 nm. Humification is proportional to the amount of humic matter dissolved by this extraction process, although few researchers convert results to a quantitative measure of humification expressing results as percentage light transmission through the peat. This paper uses luminescence spectroscopy to assess the chemical composition of these extracts. Luminescence excitation and emission wavelengths suggest that high molecular weight acids ('humic acids') are altered by the extraction procedure to form lower molecular weight acids ('fulvic acids'), amino acids and polysaccharides. Percentage transmission is principally related to luminescence emission wavelength and thus to molecular weight of the compounds present. Luminescence emission shows much more sensitivity to peat composition and demonstrates that different plant species may be affected to different degrees by the NaOH extraction process. The findings broadly support the underlying principle of colorimetric determination of 'humification' whereby transmission levels decrease with increasing plant breakdown, but show that it is based on an inadequate understanding of the chemical processes occurring in peat decay and preparation procedures. Luminescence spectroscopy provides a technique for resolving these issues.

Rapid, automatic scanning of reflectance variations along pear profiles from Corlea, central Ireland, known to contain prehistoric tephra layers dared to around 2300 cai. Be, has enabled the detection of these layers by non-destructive means. By using both light reflectance and luminescence properties it is believed that very thin and often discontinuous distal tephras characteristic of the Late Quaternary in northwest Europe may be detected within pear profiles.

The period since the mid-19th century, when instrumental meteorological recording first started in Iceland, has shown climate conditions close to, or even at, both Holocene minimum and optimum levels. The 19th century part of the Little Ice Age represents a thermal minimum, whilst the warmest decades of the 20th century are close to the estimated Holocene thermal maximum. A model describing sea ice-climate-ELA relationships in Northern Iceland for this period has been developed, providing a calibrated proxy climate record as a basis for palaeoclimatic reconstruction for the Holocene as a whole. Glacier advances in the periods around 4700 BP, around 4200 BP, ca. 3200-3000 BP, around 2000 BP, around 1500 BP and around 1000 BP, based on radiocarbon dating and tephrochronology, mark climatic minima of the post-Preboreal Holocene, when conditions were comparable to the extremes in the second half of the 19th century. Compared to optimal Holocene thermal conditions, with temperatures at least as high as in the 1930s, the range of Holocene temperature variation was ca. 3 K. This was accompanied by a doubling in precipitation from the thermal minima to the maxima.

Recent research has suggested that both raised and blanket bogs can provide proxy climate signals from variations in peat humification. In particular, oceanic margin sites have provided sensitive records that demonstrate century scale variations in humification. However, previous research has not compared records of peat humification with other terrestrial palaeoclimate proxies. Here, two records of climate change from an oceanic marginal site in NW Scotland are analysed. One, from a blanket bog, is derived from peat humification and covers the period 2100-100 BP. A second, from two stalagmites in a cave overlain by the bog, is derived from stalagmite luminescence wavelength variations for the samples deposited over 2500-0 BP. Both peat humification and stalagmite luminescence records demonstrate 90-100 year oscillations in bog wetness, that are attributed to variations in rainfall intensity or totals over this time period. It is argued that this is probably generated by a southward shift of the path of northern hemisphere depression tracks, possibly linked to variations in solar output.

Analyses of pollen, tephra, mineral input and degree of peat humification from three neighbouring raised peat profiles at Corlea, central Ireland, covering the period of the deposition of a tephra layer dated to just before 2290 cal. BC, and thought to represent Hekla-4 (2310 ± 20 BC), are used to show the problems of relying on data from a single profile when invoking relationships between volcanic activity, climate and ecosystem response. While there appears to be a strong correlation between tephra deposition and flooding of the hog surface in one profile, with a short-lived increase in the rate of peat accumulation, comparison with the other two records suggests that peat had already begun a trend to a less humified condition before tephra deposition, and that evidence of local bog surface flooding was neither consistent nor synchronous.

Seven stable moraine surfaces in Trollaskagi, northern Iceland, were sampled to produce frequency distributions of the sizes of up to 1000 Rhizocarpon geographicum s.l. thalli at each site. All frequency distributions showed a similar form, with patterns of disruption at the same points in the curves. In order to examine the possible cause(s) of this disruption, the structure of the observed distributions was compared with randomly generated distributions of lichen sizes. In the absence of snowpack data, temperature observations for the last 115 yr were used to produce duplicated model runs simulating the potential effects of snowkill on the lichen communities, producing results in close agreement with the observed data. It is concluded that in this area of northern Iceland, lichen growth was disrupted at four periods over the last 120 yr, and that at these periods possibly 80 to 100% of lichen thalli may have been lost. This has implications for lichenometric dating of moraines in the region, but as yet it is not possible to determine whether disruptions were solely due to climate, or to a combination of factors, including competition.

In order to provide a better chronological constraint on a British Middle Pleistocene interglacial, a large stalagmite boss from the Mendip Hills was selected for palaeoclimate data using pollen analysis. Dating analyses by thermal ionisation mass spectrometry (TIMS) of uranium-thorium ratios and by magnetostratigraphy constrain the age of the sample to 450-780 ka. The isotopic consistency of the TIMS analyses, plus the presence of luminescence laminations, suggest that the sample has been preserved under closed-system conditions. Pollen assemblages have been recovered from the speleothems, despite the fact that the pH of calcite deposition is usually greater than 7. Furthermore the evidence presented here indicates that the pollen was probably transported by the speleothem feedwater, rather than entering the cave aerially. The pollen record contained within the stalagmite is interpreted as early-mid-interglacial but does not have clear Cromerian affinity. © 1997 by John Wiley & Sons, Ltd.

Pollen and macrofossil analyses of raised bog peats associated with prehistoric wooden trackways at Corlea, Co. Longford, reveal a series of environmental changes on the 'dry' land bordering the extensive (and now commercially worked) bog and on the bog itself. An early form of land clearance of a landnam type, lasting about 250 years, occurred in conjunction with an elm decline at 5100 radiocarbon years BP (3890 BC in calibrated years). This pre-dates the earliest trackway, Corlea 9, dated to 3580 BC, which was built at a time for which there is no direct palynological or archaeological evidence of nearby human activity. Pollen found in association with the trackway indicates the presence of cleared areas not registered in the bog record. The apparent absence of human activity for about a millennium after this time, as illustrated in the pollen record from the peat, is questioned on the basis of the trackway pollen record and the sudden expansion of Fraxinus (ash) at 3000 BC. The possibility of a form of limited forest farming which is not registered in the pollen record from the bog, but which would have encouraged ash and hazel, is proposed. © ROYAL IRISH ACADEMY.

Comparison of the equilibrium line altitudes (ELAs) for the present (1980s) and the maximum "Little Ice Age' depression determined for glaciers in the Skioadalur/Svarfaoardalur area of the Trollaskagi peninsula, northern Iceland, shows a rise of c50 m over the last 100-150 years. Meteorological data suggest that over the same period the mean summer temperature at the equilibrium line changed by at least 2.0°C. Application of a model of the relationship between mean summer temperature and winter accumulation at the ELA for glaciers in southern Norway suggests that such a temperature change should have led to a movement of up to 300 m in the ELA. The discrepancy between the observed and expected results is accounted for by an almost two-fold increase in winter accumulation. -from Authors

The 18 papers, all abstracted separately and published mainly in Geographical Abstracts: Physical Geography, are based on a meeting held in the Department of Geography, University of Aberdeen, in April 1989. These research studies explore the patterns of climatic and environmental changes in Iceland since the end of the last glaciation. -J.W.Cooper

The coastal areas of eastern Scotland have few sites which have been investigated palynologically. This has had several consequences: most observations on the Scottish late-glacial period have been made using evidence from the west coast or from mountain massifs; the construction of isopollen maps has suffered from a lack of evidence from the east coast; vegetation change induced by humans has not always been examined for areas where their earliest activity was likely. This paper shows that evidence does exist for the Bøiling-Older-Alerød oscillation in eastern Scotland, that some presently suggested tree-spread isochrones are located too far to the south and that palynology deserves to be regarded as a diagnostic rather than merely a supporting tool for evaluating human-induced landscape change. © 1991.

Mapping and detailed morphological evidence suggests that mounds and ridges at 1200 to 1350 m in upper Breiseterdalen, western Jotunheimcn probably represent Rogcn moraines, ice sheet marginal moraines and a cirque moraine. 14C dates from an intermoraine hollow suggest that peat development began about 8800 BP, confirming a Prcboreal age for dcglaciation. A need for a revised dcglaciation chronology is suggested, with evidence for active ice present comparatively close to the present glacier limits until a late stage of dcglaciation. A possible correlation of the Breiseterdalen moraines with similarly dated marginal moraines in southwest Norway is discussed. © 1990 Taylor & Francis Group, LLC.

Detailed stratigraphic, palaeobotanical (diatom and pollen) and radiometric evidence from a sequence of buried estuarine deposits, buried peat and overlying estuarine ‘carse’ deposits at Wester Rhynd, in Lower Strathearn, suggests the occurrence of two brief marine incursions between the abandonment by the sea of a buried estuarine flat, probably the Low Buried Beach, at about 8765 ± 75 BP, and c. 8500 BP. The first incursion, shortly after 8565 ± 85 BP, caused bottom‐living marine diatoms to be thrown without clastic material onto the rapidly accumulating terrestrial peat. The second, bracketed by dates of 8485 ± 80 and 8510 ± 85 BP, deposited an extremely thin (1 mm) layer of fine sand that interrupts an otherwise unbroken buried peat succession covering the period 8765 ± 75 to 7710 ± 70 BP. The marine diatom, lithostratigraphic and 14C evidence together are consistent with a storm, storm‐surge or tsunami origin for these events, which are recognised principally from the diatom evidence, having left no mark in the pollen record. Copyright © 1989 John Wiley & Sons, Ltd

Present‐day pollen assemblages from 38 sites within differing but closely juxtaposed plant communities from the Storbreen glacier foreland in southern Norway, provide evidence for the degree to which these plant communities can be characterized by distinctive pollen assemblages. Multivariate statistical analyses of the data demonstrate a broad, tripartite division in the pollen record which reflects the three major vegetation types: (i) Pioneer Poa alpina–Trisetum spicatum community; (ii) Snowbed Salix herbacea‐dominated community; (iii) Dwarf‐shrub heath community. Occasional overrepresentation of Salix, Oxyria and Cyperaceae pollen leads to assemblages that are difficult to characterize and remain outside all major groups. Four general pollen indices are derived, each of which provide maximum limiting estimates for the proportion of pollen derived from different potential source areas. Combined with isopollen mapping the indices suggest that in pioneer communities between 20–40% of pollen collected within the community could have derived locally i.e. within the 16 m2 quadrat, whereas in the dwarf‐shrub heath this figure rises to over 60%. The remaining pollen largely originates from long distance transport, i.e. < 1 km, with little movement of foreland‐derived pollen across the foreland itself. Thus the ‘extra‐local’ component appears to play a relatively insignificant role within the area of study. The ability to separate such local and long‐distance elements will prove of particular value in the reconstruction of the history of plant communities beyond the tree‐line. Copyright © 1989, Wiley Blackwell. All rights reserved

14C dating and pollen analytical evidence is presented relating to the usefulness of arctic‐alpine Brown Soils for palaeoenvironmental reconstruction. A present‐day soil has been examined together with its continuation beneath the outermost ‚Little Ice Age’ end moraine of the glacier Vestre Memurubreen at a location well above the tree‐line in the mid‐alpine belt of southern Norway. Fourteen 14C dates from chemically‐fractionated soil samples, which range in age from 495 ± 55 14C yr in the uppermost 1 cm to > 4000 14C yr within 13 cm of the buried soil surface, demonstrate near‐linear age/depth gradients in the palaeosol. Continuous development of the palaeosol over at least 5000 calendar yr prior to burial confirms that Vestre Memurubreen attained its Neoglacial maximum extent in the ‚Little Ice Age’. Pollen stratification in buried and unburied profiles indicates a single vegetation change from a low‐alpine dwarf‐shrub heath to a mid‐alpine ‚grass’ heath, reflecting an altitudinal lowering of vegetation belts and a possible climatic cooling of 2‐4°C. Surface additions of allochthonous (aeolian) mineral particles appear to have contributed to soil development, whilst mixing processes have been relatively unimportant at this site. The immobilisation of resistant organic residues and the ineffectiveness of biological and chemical activity are major reasons for the preservation of a palaeoenvironmental record in these high altitude soils. Copyright © 1987 John Wiley & Sons, Ltd

Results of lichenometry and rock-weathering studies on outer moraines in Skidadalur show a late Little Ice Age 19th century maximum for all glaciers except the Klaengsholl glacier. Retreat from these maximum positions occurred in three distinct phases: 1896-1908, 1915-1926, and post-1930. -from Author

14C dating and pollen analysis of the surface organic (LFH) horizons of several humo‐ferric podzol profiles forming a soil catena close to the ‘Little Ice Agc’ outer moraine ridge of Haugabreen, southern Norway, are used to examine the timing and nature of podzol development at the low‐/sub‐alpine margin of the Jostedalsbreen area. Comparison with results from a palaeosol buried beneath the outer moraine shows that FH horizon development began as early as 5,265 ± 65 B.P. but that it was not synehronous across the profiles, the latest profile having a date of 3,590 ± 65 B.P. It is argued that surface organic horizons developed as a response to a deterioration of climate and possibly the recrudescence of the Myklebustbreen ice cap at c. 5,000 B.P. and that the dates for horizon initiation vary according to local topographic and soil‐hydrologic conditions. It is still uncertain whether the hump‐ferric podzols were preceded by brown earths or weakly podzolised sub‐alpine podzolic soils, but at all sites where pollen evidence is available it appears that FH initiation took place beneath Betula woodland. Copyright © 1987, Wiley Blackwell. All rights reserved

Results of chemical, palynological and 14C analysis of a palaeosol buried by proglacial lake sediments are presented. The palaeosol resembled a thin Arctic Brown Soil. Chemical analyses and 14C dates indicated that the soil was relatively young and immature at its time of burial. Soil pollen showed a sparsely vegetated surface dominated by Graminaceae and Ranunculaceae during soil development. It is concluded that burial of the soil occurred as result of ‘Little Ice Age’ expansion of Leirbreen, probably around 200 years ago. The palaeosol is not considered to represent a Preboreal soil, but rather a phase of pedogenesis initiated sometime after 1400 Calendar years B.P. © 1987, Taylor & Francis Group, LLC. All rights reserved.

Moss and grass remains associated with a well‐developed in situ palaeosol buried beneath a moraine ridge in front of Nigardsbreen (Jostedalsbreen ice cap, southern Norway) have been 14C‐dated. Pollen preserved with the plant remains suggests the existence of an agricultural landscape prior to the deposition of the moraine. The calibrated dates and the pollen spectra are in close accord with historically‐documented evidence for the timing and palaeoenvironment of the ‘Little Ice Age’ advance of the glacier. Considerable potential is indicated for estimating the maximum ages of moraine ridges and for palaeoenvironmental reconstruction where such documentary evidence does not exist. Copyright © 1986 John Wiley & Sons, Ltd

Pollen analysis and radiocarbon dating of a 2.12 m blanket peat profile from Black Ridge Brook, northern Dartmoor, reveals the presence of deposits of Lateglacial/early Flandrian age. Sites of this period are rare in the South West and central southern England as a whole. Pollen assemblages show the persistence of open ground plant communities into the Flandrian and the radiocarbon dating implies a significant delay in woodland development. This delay was caused by a combination of edaphic and climatic factors, but there is evidence for the early influence of fire, Birch-hazel woodland spread onto the higher areas of Dartmoor by c8000 BP but treelines began to fall by c7700-7600 BP. From this time charcoal is continually present in the profile and woodland recession and blanket peat development were, at last in part, due to the activities of Mesolithic communities.-Authors

Forest probably covered nearly all of Dartmoor during the earlier and middle Flandrian (9500-5000 bp) although there remains a possibility that the highest elevations carried moorland. -from Authors

Survey of the marginal area of Gljufurarjokull in 1983 has showed the glacier to have advanced 25 m between 1981 and 1983. Detailed surveying and sampling of a largely depositional feature found at the ice margin suggested that it was formed very rapidly due to a 'burst' of water in the ice-marginal zone during the 1982-83 winter season. -from Author

Lichenometric studies from four glaciers are used to determine the dates of their Little Ice Age maxima. In all cases these date to the last half of the nineteenth century and probably marked the maximum Neoglacial extent of the glaciers. -from Author

Shows the substitution of a low-alpine lichen heath dominated by Empetrum and Vaccinium by a mid-alpine Salix herbacea-dominated community, reflecting an altitudinal depression of the local vegetation belts. This depression is related to climatic deterioration either at the onset of the Little Ice Age, possibly 12th century AD/13th century AD, or at an earlier period. -from Author

Pollen analysis of the organic surface (FH) horizon of a radiocarbon‐dated palaeopodzol buried beneath the ‘Little Ice Age’ outer moraine of Haugabreen west of the Jostedalsbrecn ice‐cap, southern Norway, provided evidence for environmental change in the area between ca. 4,000 B. P. and the 13th century A. D. Radiocarbon dating of the profile, apart from providing a chronology for the changes interpreted, also allowed estimation of pollen incorporation rates into the soil which can be compared with pollen influx rates established elsewhere. Two periods of local woodland recession were identified, the first between ca. 3,300 B. P. and ca. 3,600 B. P. after the initiation of the FH horizon, and the second in the 13th century A. D. at the onset of the Little Ice Age. Copyright © 1983, Wiley Blackwell. All rights reserved

Two of the principal aims of the 1981 Joint Universities (Exeter and St. Andrews) North Iceland Expedition were to resurvey the margins of Gljufurarjokull and to test the chronology proposed for the recent deglaciation of Gljufurardalur. Outlines a history of recent deglaciation based on a lichenometric survey of the sequence of morainic ridges mapped and described in 1979. -from Author

A section of the recent paper on ‘The last Scottish ice‐sheet: facts and speculative discussion’ by J. Brian Sissons (Boreas, Vol. 10, pp. 1–17) is commented upon. New dating and stratigraphic evidence from northeast Scotland is also presented. Copyright © 1982, Wiley Blackwell. All rights reserved

Archaeological excavation of barrows in the St Neot Valley on the southern flanks of Bodmin Moor revealed buried soils developed in the gravelly granitic head typical of the upland block. By comparing these soil profiles with adjacent soils we have obtained evidence for and now describe dramatic prehistoric changes in upland soils and vegetation attributed previously to various combinations of human influences and climatic events. Direct pedological and palaeoecological evidence supports the theory that brown soils existed in pre-Bronze Age times in southwestern England at a site subsequently developing an iron pan (Bf) and accumulating a strongly acid peaty surface. © 1982 Nature Publishing Group.

A review of the palaeoenvironmental evidence for the extent and form of woodland cover, soil development and role of man shows that much of Simmons' work of the 1960s is being confirmed. His plea for many more 14C dated profiles remains largely unanswered, and it is doubtful whether a very detailed regional picture can ever be obtained. -from British Archaeological Abstracts

The following sequence is proposed 1) a 'Little Ice Age' maximum marked by a clear end moraine which occurred at the end of the 19th century. 2) Retreat from this outer margin took place quite rapidly before a period of relative stillstand, tentatively dated to between 1930 and the early 1940s. 3) More recent retreat stopped between 1972 and 1977. 4) Between 1977 and 1979 the terminus of Gljufurarjokull advanced by between 30 and 50 m. The mean horizontal ice surface velocity for 1977-1979 was c.26 m/year. -from Authors

The analysis of two adjacent profiles from Stormont Loch near Blairgowrie on the southern fringe of the eastern Grampian Highlands demonstrates the existence of a comparable sequence of local pollen assemblage zones covering the Lateglacial period. The sequence of local pollen assemblage zones is dissimilar to that found at most other sites in the Grampians for there are two zones dominated by woody species, Juniperus - Empetrum and Betula - Juniperus respectively, which are separated by a Rumex - Cyperaceae zone. The sequence may represent the Bolling - Older Dryas - Allerod chronozones. -from Author

The morphological and stratigraphic studies reported here relate to early Flandrian relative sea-level changes in the carselands, or Postglacial raised estuarine flats, of Lower Strathearn. These data coupled with the study and dating of associated environmental changes by pollen and diatom analysis and radiocarbon assay, have enabled graphs of relative sea-level changes and land uplift to be constructed. © 1980 Nature Publishing Group.

Review of the available evidence, which is particularly fragmented and hard to interpret, but includes pollen, coleoptera, land mollusca, and some archaeological sites with environmental evidence. Lack of deep basins with accumulated peat is the main difficulty. -from British Archaeological Abstracts

THIS paper reports new investigations carried out on the Teindland soil profile first described by E. A. FitzPatrick1. The section (grid ref. NJ 3297 8570) lies at an altitude of about 101 m OD in a disused quarry within Teindland Forest, 5 km south-west of Fochabers in Grampian Region, Scotland. The present study presents evidence which suggests that a fossil microflora contained within the soil can be assigned to two distinct phases of geological time, the Middle Devensian interstadial and the Ipswichian stage. This is augmented by stratigraphic analyses which suggest that the site is of wider significance for the Quaternary chronology of the area than has been appreciated. © 1976 Nature Publishing Group.