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Investigations at Pepper Arden Bottoms, a lake basin site on the interfluve between the rivers Tees and Swale in northeast England, have recovered lithostratigraphical, pollen and plant macrofossil sequences which have allowed the reconstruction of sedimentary and vegetation history from the Lateglacial Interstadial to the post- Ulmus Decline mid-Holocene. Although the calcareous nature of the sediment and lack of terrestrial plant macrofossils precluded radiocarbon dating of sediments pre-dating the Ulmus Decline, pollen analyses showed sediment accumulation from the middle of the Lateglacial Interstadial, with the lake catchment remaining poorly vegetated until the Holocene, with low values for woody taxa, and grasses and sedges dominant. The late Interstadial cold phase GI-1b is present in the pollen stratigraphy, with a major reduction in Betula frequencies, replaced by Juniperus , and an increase in cold-tolerant herbs, mainly grasses and sedges. Microcharcoal frequencies are consistently substantial throughout the Lateglacial levels, probably indicating a natural fire regime, but are absent from the Holocene, suggesting little Mesolithic or Neolithic activity nearby, which is confirmed by a lack of pollen indicators of disturbance. The Lateglacial (Loch Lomond) Stadial is entirely dominated by Cyperaceae and Poaceae pollen, with very few trees and shrubs. The successive migration of postglacial thermophilous trees is recorded in the Holocene and possible effects of the Preboreal Oscillation and the 8.2 ka BP cold events are recognised. An Ulmus Decline occurs near the top of the profile, after which the assemblage is dominated by Alnus as the lake became terrestrialised and was occupied by fen and then alder carr. The very open Lateglacial vegetation adds this site to a northern group in northeast England with poor Lateglacial woodland development, in contrast to sites to the south, in North Yorkshire, where Lateglacial Betula woodland was much better established. [ABSTRACT FROM AUTHOR]

Holocene relative sea-level reconstructions reveal spatial and temporal patterns, indicating the importance of regional- to local-scale processes for understanding coastal evolution. We reconstruct the Holocene sea-level history and coastal evolution of the north-western Fenland using detailed analyses of lithostratigraphy, microfossil (foraminifera and pollen) assemblages and a suite of 18 radiocarbon dates. We illustrate the balance between sea-level change, sedimentary palaeoenvironment and coastline movements. An initial transgression occurred c . 7700 cal. BP as sea level rose around 8 mm/yr, reaching its maximum inland extent c . 4150 cal. BP. As the rate of sea-level rise reduced to less than 2 mm/yr, a series of local regressive and transgressive phases followed. A regional transgressive event inundated much of the area after c . 2600 cal. BP. Salt marsh peat and intertidal mud dominate inland sequences whereas further seawards, intertidal and subtidal nearshore sand occur, comparable with modern sediments of the adjacent Wash embayment. The north-western Fenland sequence shows similarities with sequences in southern Fenland and The Wash, indicating some regional sea-level control. [ABSTRACT FROM AUTHOR]

The transition to the Late Holocene/Neoglacial occurred as a worldwide process of climatic deterioration from the optimum thermal conditions of the mid-Holocene, culminating in an abrupt decline around 4200 cal yr ago, in a period of severe climatic deterioration that lasted for two or three centuries. This sudden climatic event has been recorded in many proxy data archives from around the world, and its effects were manifest in different ways depending on the reaction of regional weather systems and conditions, but often as greatly increased aridity and/or cold temperatures. It has been regarded as causing or contributing to the sudden collapse of several well-established human societies at that time, including advanced agricultural Late Neolithic cultures in eastern China. We have used high-resolution pollen and non-pollen palynomorph analysis to examine the nature of this climatic transition through its impacts on the vegetation and hydrology at Pingwang, a site in the Yangtze coastal lowlands which has no evidence of complicating environmental influences such as sea-level rise or significant human land-use activity, factors previously suggested as alternative reasons for changes in forest composition. Our results show two phases of forest alteration, one gradual from about 5500 cal BP and one sudden at about 4200 cal BP., in which the frequencies of subtropical forest elements fall and are replaced by those of conifers and cold-tolerant trees. Total arboreal pollen frequencies do not decline and the proportion of temperate forest trees, tolerant of a wide range of temperatures, remains unchanged throughout, both ruling out human land clearance as a cause of the change in forest composition. As these dates accord very well with the known timings of climate deterioration established from other proxy archives in the region, we conclude that climate was the main driver of vegetation change in eastern China at the mid- to Late Holocene transition. Our hydrological results support the view that a combination of rising local water level and climatic cooling during the 4200 cal BP event was the probable cause of societal collapse in the lower Yangtze valley. [ABSTRACT FROM AUTHOR]

Abstract: The transition in north-west Europe from the hunter–gatherer societies of the Late Mesolithic to the pioneer farming societies of the early Neolithic is not well understood, either culturally or palaeoecologically. In Britain the final transition was rapid but it is unclear whether novel Neolithic attributes were introduced by immigrants who supplanted the native hunter–gatherers, or whether the latest Mesolithic foragers gradually adopted elements of the Neolithic economic package. In this study, relatively coarse- (10 mm interval) and fine-resolution (2 mm), multi-proxy palaeoecological data including pollen, charcoal and NPPs including fungi, have been used to investigate two phases of vegetation disturbance of (a) distinctly Late Mesolithic and (b) early Neolithic age, at an upland site in northern England in a region with both a Neolithic and a Late Mesolithic archaeological presence. We identify and define the palaeoecological characteristics of these two disturbance phases, about a millennium apart, in order to investigate whether differing land-use techniques can be identified and categorised as of either foraging or early farming cultures. The Late Mesolithic phase is defined by the repetitive application of fire to the woodland to encourage a mosaic of productive vegetation regeneration patches, consistent with the promotion of Corylus and to aid hunting. In this phase, weed species including Plantago lanceolata, Rumex and Chenopodiaceae are frequent, taxa which are normally associated with the first farmers. The early Neolithic phase, including an Ulmus decline, has characteristics consistent with ‘forest farming’, possibly mainly for domestic livestock, with an inferred succession of tree girdling, fire-prepared cultivation, and coppice-woodland management. Such fine-resolution, potentially diagnostic land-use signatures may in future be used to recognise the cultural complexion of otherwise enigmatic woodland disturbance phases during the centuries of the Mesolithic–Neolithic transition. [Copyright &y& Elsevier]

Abstract: The date and location of the adoption of rice cultivation by foraging cultures in China are of considerable current interest but its understanding is hampered by lack of information regarding its palaeoenvironmental context. We present detailed multi-proxy palaeoecological research at the earliest-dated site of rice cultivation in the coastal littoral of east China which has revealed the precise environmental setting of this early Neolithic settlement and its incipient cultivation at ca 7750calBP. Regional and local environmental changes governed the character of the site and the duration of human activity. After an episode of marine conditions, natural hydrological succession and terrestrialisation of the site preceded fire clearance of marsh fen-carr alder scrub that prepared the ground for cultivation and then maintained a reedswamp-type wet grassland in which rice was grown. Cropping of Typha stands may have formed part of the subsistence base before the site was overwhelmed by marine inundation ca 7200calBP, after which rice cultivation spread to Neolithic sites of Hemudu type elsewhere in the coastal lowlands. We suggest that integrated multi-proxy palaeoecological studies are vitally important for the full understanding of such key wetland archaeological sites. [Copyright &y& Elsevier]

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]