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Abandoned river channels may provide rich primary sources of palaeoenvironmental and cultural information elucidating landscape evolution, climate change, vegetation history and human impact, especially since the beginning of the Holocene epoch. However, although potentially an important resource, palaeochannels are not often recorded systematically and only rarely enjoy robust statutory protection (in the UK as Sites of Special Scientific Interest). In consequence, it is challenging to mitigate and manage this important geoarchaeological resource effectively within the UK planning framework. Whilst palaeochannels have long been recognised on aerial photographs and historic maps, the advent of airborne laser scanning (Lidar) and other remote-sensing technologies has provided a hitherto unforeseen opportunity to record such landforms and related features at a catchment scale. This paper provides a case study from the Nottinghamshire reach of the Trent Valley, where a desk-based methodology that is now being extended across the entire catchment has been developed for recording, geospatially locating and defining the attributes of observed palaeochannels. After outlining the methodology, we consider how this approach to resource management can aid archaeological research and future heritage management, especially in the light of predicted climate and environmental change. [ABSTRACT FROM AUTHOR]

Increasing consideration is being given as to whether and how the subsoil can be utilised as a resource to store greater quantities of organic carbon through a range of 'frontier' technologies. However, recent work suggests 'priming' effects may occur when fresh soil organic carbon (SOC) is mixed with older organic carbon (OC). Combined with increasing intensity of land use and perturbation of the surface environment there is potential for buried organic carbon (OC) to be re-incorporated into the active global C cycle. Therefore, understanding the nature of existing buried organic carbon (OC) within Soil Parent Material (SPM) and landscapes is increasingly important. A major OC burial route within landscapes is via erosion and deposition processes. This paper aims to provide a 'first order' overview of the role erosion processes have made since the UK Last Glacial Maximum (UK-LGM) in the burial of OC in Great Britain. Using collated information, Monte-Carlo simulations were used to produce 'first-order' estimates of the mass of OC buried within three deposit types; Devensian Till, Devensian Glacio-fluvial deposits and Holocene Alluvium. Combined median estimates for these three deposit types alone suggest, that 385 MT of OC has been buried in these deposits across Great Britain, demonstrating the importance of post UK-LGM erosion processes in long-term sequestration of OC. The paper provides a basis of a framework to describe where buried OC may be found within UK SPM and landscapes, whilst identifying gaps in our knowledge base. Whilst focusing on Great Britain, the processes are relevant to many countries, each of which will have experienced erosion processes unique to their own history of geology, geomorphology and climate. • Post UK-LGM erosion processes are assessed in relation to organic carbon burial. • The climate-vegetation-erosion concept was used to assess erosion processes. • Climate helped determine deposit thickness and carbon concentration. • Estimates of organic carbon burial in selected deposit types were 385 Mt C. [ABSTRACT FROM AUTHOR]

The recognition of Mesolithic impacts in mid Holocene pollen diagrams of the British Isles has led to the development of models describing sophisticated woodland management, particularly through the use of fire, by Mesolithic populations. However, the significance of human agency in creating mid Holocene woodland disturbances is unclear, with natural and human-induced clearings arguably indistinguishable in the pollen record. Analysis of non-pollen palynomorphs (NPPs) should aid the identification of events and processes occurring within these woodland disturbances and provide more precise palaeoecological data. In this paper we present pollen, charcoal and NPP analyses from a potentially critical location in the Mesolithic impacts debate. NPP types aid significantly in the reconstructions, suggesting periods of dead wood, grazing, local burning and wetter ground conditions. The results indicate that between 7700 and 6800 cal b.p., a predominantly wooded environment periodically gave way to phases of more open woodland, with inconsistent evidence for animal grazing. From 6800 cal b.p., a phase of open woodland associated with high charcoal concentrations and indicators of grazing was observed. This probably represents the deliberate firing of vegetation to improve grazing and browse resources, although it remains unclear whether fire was responsible for initially creating the woodland opening, or if it was part of an opportunistic use of naturally occurring woodland clearings. [ABSTRACT FROM AUTHOR]

River basins in Great Britain and Ireland have been characterized by periods of hillslope and valley floor instability during the Holocene, reflecting sensitivity to both climate change and anthropogenic disturbance. In contrast to climatic controls, which have been relatively well documented, human impacts on and interactions with river basins remain unclear. There is now, however, a growing impetus to elucidate more fully the impact of anthropogenic activity on sediment supply and runoff, given that land-use change is thought to have exacerbated recent flooding in the UK (eg, the 'Millennium' floods of 2000). The aim of this paper is to critically review the significance of Holocene land use on hillslope and valley floor stability in Great Britain and Ireland. The most widely reported impacts of land-use change on geomorphic activity include hillslope erosion and gully development, valley floor alluviation, river channel incision and elevated water tables. In the majority of cases, however, causal relationships are difficult to establish, due primarily to inadequate dating control. Even where geomorphic instability can be linked to land-use change, it is apparent that eroded material is often stored as colluvium, which together with evidence of diachronus hillslope and valley floor instability, raises important questions and identifies uncertainties regarding the dynamics and extent of sediment transfer within river basins. Such uncertainty has important implications for understanding how river basins will behave in response to future environmental change. [ABSTRACT FROM AUTHOR]

Relative sea-level changes in southwest Britain are poorly constrained because of limitations in the quality and quantity of existing geological data. As a consequence, in contrast to most other regions in the UK, it is not possible to reliably infer rates of land and sea-level change during the last few thousand years. Furthermore, geologically based sea-level reconstructions from this area display significant misfits with relative sea-level predictions based on a recent global model of the glacio-isostatic adjustment process. This paper presents a new record of relative sea-level change for the last 4000 years derived from radiocarbon-dated sea-level index points. In addition to providing information concerning the pattern and rates of late Holocene sea-level change, these data are used to evaluate the suggestion that the apparent misfits between model predictions and geological reconstructions can be satisfactorily explained as a consequence of the lowering of sea-level index points by sediment compaction. The results indicate that a simple, first-order method of decompaction based on the stratigraphic position of sea-level index points, can eliminate much of the misfit between reconstructions and predictions, and substantially reduce vertical scatter in geological data. They also suggest that the influence of compaction on sea-level data from this region may be larger than previously thought. The simple addition of reliable stratigraphic data, in combination with targeted sampling, has the potential to improve our understanding of the compaction process, and increase the utility of existing data. This is increasingly important as the partnership between geophysical modelling and geological investigation becomes more commonplace in sea-level studies around the world. [ABSTRACT FROM AUTHOR]

Species reintroductions are a core component of conservation but require critical assessment of past baselines. The Dalmatian Pelican Pelecanus crispus formerly occurred in Britain during the Holocene and there is interest in its possible reintroduction, but its regional extinction dynamics remain poorly understood. Pelican bones are known from subfossil and zooarchaeological contexts at 11 British Holocene sites in three regions (East Anglian Fens, Somerset Levels and Moors, Humber Valley). Dalmatian Pelican is positively identified from four of these sites, with other specimens only identified to genus level. Pelican populations were probably only present periodically in Britain during intervals of suitable climate and available habitat: there is little evidence for pelicans before the Bronze Age, and most sites are known or inferred to be Iron Age. There is a suggested Medieval specimen but no secure evidence of pelican presence after the Roman period. However, no specimens are directly dated, with age estimation reliant upon indirect dates or inference. Climatic niche modelling indicates that southern Britain was the northwestern limit of pelican climate tolerance under postglacial conditions, and pelicans may have been unable to persist regionally until the mid‐ or late Holocene. Considerable pelican breeding and foraging habitat might have existed until the Medieval period, but availability of suitable habitat fluctuated throughout the Holocene. Probabilistic analysis suggests possible mean extinction date estimates between ad 589 and ad 1587, highlighting uncertainty associated with indirect data, and hindering our ability to correlate pelican disappearance with putative extinction drivers (overexploitation, human modification of wetlands, or non‐anthropogenic environmental changes). Improving our understanding of conditions associated with past pelican occurrence is essential for potential reintroduction decision‐making, and direct dating of bones from all sites is needed to establish a secure chronological framework for correlating pelican presence and disappearance with regional landscape change. This review provides a robust framework for how to integrate past environmental baselines into conservation decision‐making and reintroduction feasibility assessments. [ABSTRACT FROM AUTHOR]

The Isle of Man is a large island which lies in the middle of the northern Irish Sea between Britain and Ireland and, because of its insularity and size, has an impoverished flora compared with the two main islands. This has been the case throughout the postglacial and warrants the island's description as a separate phytogeographic province. We have considered Holocene tree pollen data from seventeen sites on the island which together preserve a vegetation history that spans the six thousand years of the early and mid-postglacial from the end of the Lateglacial at 11,700 cal. BP to the mid-Holocene Ulmus decline at ca. 5800 cal. BP. Radiocarbon dating of the rational limits of the pollen curves for the main tree taxa has allowed an appraisal of the timing of each one's expansion to become a significant component of the island's woodland, and comparison with the dates of their expansion on the adjacent regions of Britain and Ireland. The radiocarbon dates show that, although some variability exists probably due to local factors, there is considerable concordance between the timings of major pollen zone boundaries in Britain and Ireland around the northern Irish Sea. On the Isle of Man the expansions of both Juniperus and Betula were delayed by several centuries compared to the British/Irish data, however the timing of the expansions of Corylus, Ulmus, Quercus, Pinus and Alnus on the Isle of Man all appear closely comparable to the ages for these pollen stratigraphic events in north Wales, northwest England, southwest Scotland and eastern Ireland, as are those for the Ulmus decline. It is likely that local pedological and edaphic factors on the island account for the differences in the first Holocene millennium, while regional climatic factors governed the timings for the rest of the expansions of tree taxa across the wider region, including the Isle of Man. Disturbance, including by human agency, was important at the site scale and perhaps triggered early tree expansion in some places, including Quercus, Ulmus and Alnus. Insularity seems not to have been a significant factor in the expansion of the major forest trees. [ABSTRACT FROM AUTHOR]

In this paper we report new data on peat carbon (C), nitrogen (N) and phosphorus (P) concentrations and accumulation rates for 15 sites in the UK. Concentrations of C, N and P measured in peat from five ombrotrophic blanket mires, spanning 4000–10,000 years to present were combined with existing nutrient data from ten Scottish ombrotrophic peat bogs to provide the first UK perspective on millennial scale macronutrient concentrations in ombrotrophic peats. Long-term average C, N and P concentrations (0–1.25 m) for the UK are 54.8, 1.56 and 0.039 wt%, of similar magnitude to the few published comparable sites worldwide. The uppermost peat (0–0.2 m) is enriched in P and N (51.0, 1.86, and 0.070 wt%) relative to the deeper peat (0.5–1.25 m, 56.3, 1.39, and 0.027 wt%). Long-term average (whole core) accumulation rates of C, N and P are 25.3 ± 2.2 gC m − 2 year − 1 (mean ± SE), 0.70 ± 0.09 gN m − 2 year − 1 and 0.018 ± 0.004 gP m − 2 year − 1 , again similar to values reported elsewhere in the world. The two most significant findings are: 1) that a regression model of N concentration on P concentration and mean annual precipitation, based on global meta data for surface peat samples, can explain 54% of variance in N concentration in these UK peat profiles; and 2) budget calculations for the UK peat cores yield an estimate for long-term average N-fixation of 0.8 g m − 2 year − 1 . Our UK results, and comparison with others sites, corroborate published estimates of N storage in northern boreal peatlands through the Holocene as ranging between 8 and 15 Pg N. However, the observed correlation of N% with both mean annual precipitation and P concentration allows a potential bias in global estimates that do not take this into account. The peat sampling data set has been deposited at the NERC Data Centre ( Toberman et al., 2016 ). [ABSTRACT FROM AUTHOR]

We present and appraise a large compilation of peatland palaeoecological research in Great Britain, and discuss the value of these data for secondary analysis. We identify 475 radiocarbon-dated palaeoecological records from British peatlands published since 1970. Peatland palaeoecological research has been widespread but with some clear spatial biases reflecting factors such as accessibility and the location and interests of active researchers. We show that basic details such as stratigraphic descriptions, site coordinates and full details of radiocarbon dates are omitted from publications with surprising frequency and note the large quantity of data that only ever appears in PhD theses. To allow papers to remain concise while presenting essential background information we propose a system of standardised meta-data in online supplementary material. The extensive body of palaeoecological data for British peatlands has been relatively unexploited. The compilation we present will be a valuable aid in making better use of this data resource. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

Abstract: Lake sediments can play an important role in understanding and reconstructing temporal characteristics of the geomagnetic field, as they potentially offer near continuous high-resolution archives of magnetic information extending throughout the Holocene. To date lake sediment geomagnetic data has typically been excluded from British archaeomagnetic secular variation curves (SVC) due to uncertainties with the acquisition of magnetisation by lake sediments. This paper presents the argument that, with regards to British datasets, the real problem lies with poor chronological control and sets out to illustrate that with British archaeomagnetic data some progress has been made. The results indicate that it is not currently possible to resolve secular variation on a time scale of ∼100years from published British lake sediment data but more success has been made with data from archaeological sediments. This level of detail has been considered necessary for the incorporation of lake sediment data into the British archaeomagnetic dataset, as the ability to resolve short-term geomagnetic changes is critical for the integration of any dataset into the British SVC. As the latter is predominantly employed to date archaeological architecture and artefacts requires that it has the ability to resolve changes over timescales relevant to human lifetimes. Using currently available data this retrospective critique confirms that, in archaeological sediments, depositional and thermoremanent magnetisation can record the same direction over the same time interval. [Copyright &y& Elsevier]

Interglacial fluvial sediment sequences are common in lowland Britain where their palaeontology has been considerably studied but their sedimentology is poorly known. By contrast, Holocene (Flandrian) sequences have yielded important insights into river, and thus, environmental evolution. This paper examines the nature of the interglacial fluvial sedimentary record in southern Britain, showing similarities and differences in the sedimentary record. A four-phase pattern of fluvial behaviour through an interglacial cycle is presented. The utility of using Holocene sequences as analogues for previous interglacial sedimentation is discussed and an attempt is made to explain the proposed four-phase pattern in terms of predictable fluvial responses to an interglacial climate cycle. Finally, the implications of the pattern for alluvial unit preservation and the stratigraphical interpretation of Pleistocene temperate events from river sediments are highlighted. It is shown that British lowland rivers normally adopt three major behavioural modes in the Pleistocene: braided or wandering gravel-dominated mode, fine-sediment-dominated stable meandering to anastomosing mode, and incision or non-depositional mode. [Copyright &y& Elsevier]

The geochemistry of Arctica islandica shells provides an opportunity to reconstruct intra-annual resolution climate records in temperate latitudes, and the annual banding allows close temporal constraint. Stable isotope analyses of carbon and oxygen from an Arctica islandica live-collected at 6 m depth from Irvine Bay, UK are presented. Seawater temperature ranges reconstructed from shell δ18O agree, within error, with instrumental sea surface temperature measurements. The saw-tooth profile of the seasonal δ18O signal (compared with the sinusoidal seawater temperature) indicates that shell accretion rate is not constant throughout the year. Modelling the expected δ18O profile from water temperature, salinity and shell growth rate suggest that A. islandica at this site has significant variation in the shell extension rate during the year. Material deposited during shell damage shows a positive shift in δ18O. A strong ontogenetic effect is seen in δ18C and damage to the shell is associated with a significant (>0.5‰) and sustained shift of δ18C. [ABSTRACT FROM AUTHOR]

To reconstruct Lateglacial and Holocene environmental changes in the British uplands, two c. 5.8 m long sediment cores from Crummock Water (NW England), together with several hundred soil samples from the Crummock Water catchment, were studied using magnetic techniques. Optically stimulated luminescence (OSL) dating using fine silt quartz and 14C dating of terrestrial plant macrofossils were used to establish a chronology for the lake sediments. A good agreement between optical and 14C ages indicates first, that the OSL dating method can be used to date lake sediments in the British Isles; second that macrofossil-based 14C dating can be used to avoid the problem of 'old carbon' error associated with bulk sample 14C dating of lake sediments and third, that the established chronology is robust. The lake sediment magnetic properties indicate a series of changes in sediment composition during the Holocene, which correlate well with sediment lithology, water content and weight-loss-on-ignition. The first change corresponds to the Lateglacial/Postglacial climatic shift at around 11 400 years ago; the subsequent suite of changes corresponds to a probable regional onset of human activity at 2000 BC, and particularly to the intensification of human activity at around AD 900. A comparison of the lake sediment magnetic properties and those of the catchment soils shows a clear linkage for the Lateglacial period, and for the period after AD 900. In contrast, detailed magnetic measurements of the early- through mid-Holocene sediments suggest that their magnetic properties are dominated by bacterial magnetosomes. [ABSTRACT FROM AUTHOR]

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]

A high-resolution textural study has been made of laminated and banded estuarine silts exposed intertidally at representative localities and horizons in the Holocene deposits of the Severn Estuary Levels. The laminae, on a submillimetre to millimetre scale, are sharp-based, graded couplets formed of a lower silty part overlain by a finer-textured clayey element. The centimetre- to decimetre-scale banding is formed of laminae in alternating, gradually intergrading sets of relatively coarse and relative fine-grained examples. At outcrop in the field, the banding is recognizable because the coarse sets prove to be recessive to varying degrees under the influence of weathering and current action. Independent evidence at two localities points toward an annual origin for the banding; at a third it arose during part of what appears to have been a relatively short period. Quantified physical arguments suggest that the textural banding is a response of suspended fine sediment to marked seasonal changes in sea temperature and windiness. The banded silts occur in four distinct stratigraphical contexts and record high deposition rates (order 0.01 À 0.1 m = yr). Because physical factors determine their textures, the silts potentially afford insights in all contexts into aspects of changing Holocene climatic conditions. In one context, the thickness of the bands points to high (order 0.01 À 0.1 m = yr) but comparatively short-lived (order 10s À 100s yrs) rates of relative water-level rise. In the others, however, the banding has no implications for sea-level behaviour, and simply records gross environmental disequilibrium, for example, the recovery of mudflats = marshes after an erosional episode. Similarly, because on account of their rapid accumulation the banded silts preserve animal and human tracks and trackways especially well, they provide an archive of animal and human behaviour in the area during the Holocene. [ABSTRACT FROM AUTHOR]