Multi-Profile Palynology of Mid-Holocene Peat at Cat Stones
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Durham Research Online Deposited in DRO: 03 September 2021 Version of attached le: Accepted Version Peer-review status of attached le: Peer-reviewed Citation for published item: Albert, Bruce M. and Innes, James B. and Blackford, Je J. (2021) 'Multi-prole ne-resolution palynology of Late Mesolithic to Bronze Age peat at Cat Stones, Rishworth Moor, Central Pennines, UK.', The Holocene, 31 (3). pp. 483-501. Further information on publisher's website: https://doi.org/10.1177/0959683620972768 Publisher's copyright statement: Albert, Bruce M., Innes, James B. Blackford, Je J. (2021). Multi-prole ne-resolution palynology of Late Mesolithic to Bronze Age peat at Cat Stones, Rishworth Moor, Central Pennines, UK. The Holocene 31(3): 483-501. Copyright c 2020 The Authors. DOI: 10.1177/0959683620972768 Additional information: Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full DRO policy for further details. Durham University Library, Stockton Road, Durham DH1 3LY, United Kingdom Tel : +44 (0)191 334 3042 | Fax : +44 (0)191 334 2971 https://dro.dur.ac.uk Multi-profile fine-resolution palynology of Late Mesolithic to Bronze Age peat at Cat Stones, Rishworth Moor, Central Pennines, UK. Bruce M. Albert1, James B. Innes2 and Jeff J. Blackford3 Abstract Palynological data from three radiocarbon dated peat profiles at Rishworth Moor in the Pennine hills of northern England provide a record of vegetation change and human impacts in the Late Mesolithic, Neolithic and Bronze Age periods. All three cultures have archaeological sites present in the vicinity, with Late Mesolithic sites by far the most abundant, comprising mainly very late assemblages dominated by ‘rod’-shaped microliths. Pollen evidence of vegetation disturbance occurs during all three archaeological periods, and is attributed to the results of human activity. Microscopic charcoal and non-pollen palynomorph analyses support the pollen evidence. Sites at Cat Stones 2 and Cat Stones 3 record evidence of Neolithic and Bronze Age date only. Cat Stones 1 extends into the Late Mesolithic period, and fine-resolution pollen analyses have been applied in this profile to the Mesolithic-Neolithic transition leading up to the mid-Holocene Elm (Ulmus) Decline, which starts here at c.4940 14C BP (5670 cal. BP), a typical date for it in the central Pennines. Bayesian age-depth modelling provides precise ages for the vegetation changes and their spatial correlation. The plateau was dominated by scrub and grassy Calluna heath from the Late Mesolithic onwards. Elevated microscopic charcoal levels and ruderal herb pollen record phases of fire disturbance below the Elm Decline, including a grain of Hordeum cereal-type. Whether this grain represents early cultivation requires further research. Bronze Age impacts are of greater intensity, but disturbances of all three cultural periods are low scale, agreeing with the results of previous research in the Pennines. 1Archaeology Department, Durham University, Science Labs, South Road, Durham, UK 2Geography Department, Durham University, Science Labs, South Road Durham DH1 3LE, UK 3School of Environmental Sciences, University of Liverpool, and University of Liverpool in London, 33 Finsbury Square, London EC1A 2AG. Corresponding author: James B.Innes, e-mail: [email protected] Keywords: High-Resolution Palynology, Mesolithic-Neolithic Transition, Bronze Age, Central Pennines, Hordeum pollen, fire disturbance 1 Introduction In Britain the later mid-Holocene, between about 5500 and 3700 radiocarbon years ago (c. 6300–c. 4000 cal. BP), contained important environmental and cultural transitions. Deciduous woodland was the natural vegetation, its composition varying with environmental factors (Bradshaw and Hannon, 2004). In the central Pennines hills of northern England the mid-Holocene woodland’s upper limit was at c.500 m above sea level, based on macrofossil tree remains (Tallis and Switsur, 1983, 1990), above which was scrub, bog and moorland, the ‘hyper-forest zone’ of Simmons (1975). As well as naturally open areas (Brown, 1997; Fyfe, 2007), mainly wetlands, millennia of disturbance by Mesolithic hunter-gatherers’ use of fire might have affected woodland density and composition, encouraging heliophyte trees and shrubs and creating an open woodland with temporary clearings (Caseldine and Hatton, 1993; Jacobi et al, 1976; Simmons and Innes, 1987). Long-term burning by foragers might have changed the woodland’s nature and sometimes even converted it to grassland, heathland or bog (Moore, 1975; Moore et al., 1984; Simmons and Innes, 1985, 1987; Simmons 1996). Climate fluctuations during this time were important, with dry conditions before 6000 cal BP, then wet phases at c.5900, c.5300 and after 4400 cal. BP, with intervening dry periods (Tipping, 1995, 2010; Hughes et al., 2000; Stolze et al., 2012). Climatic fluctuations were influential in regulating vegetation patterns and affecting human responses (Bonsall et al., 2002; Schulting, 2010; Tipping, 1996, 2010; Tipping and Tisdall, 2004). Burning during dry phases could have had a natural cause, and not all woodland disturbances need have had an anthropogenic origin (Grant et al., 2014). During this period major cultural transitions took place. One was the change from foraging (Mesolithic) to farming (Neolithic) economies and culture, occurring in the centuries leading up to and including the major decline in Ulmus (Elm) pollen frequencies that forms a key biostratigraphic marker dated to broadly 5100 radiocarbon years ago (c. 5800 cal. BP, Parker et al., 2002) in pollen diagrams. The range of radiocarbon dates for the Elm Decline in northern England is considerable (Griffiths, 2014a), from 5468±80 BP (6410-6004 cal. BP) at Neasham Fen in southeast Durham (Bartley et al., 1976) to 4644±43 BP at Bonfield Gill on the North York Moors (Innes et al., 2013; Innes and Blackford, 2017). It was multi-causal (Parker et al., 2002), with disease, Neolithic farming and climate change all contributory factors. It coincided with an early stage in the Neolithic, with significant elements of Neolithic culture and economy present. However, with a dating variability of several centuries over short distances, it is unlikely that it can be interpreted as marking the first introduction of the Neolithic to a particular location. While the ‘full’ post-Elm Decline Neolithic was 2 established by immigrant farmers (Sheridan, 2010), there might have been an ‘initial Neolithic’ before the Elm Decline, with Neolithic elements added to the Mesolithic culture. When that occurred would have varied from place to place (Noble, 2010). The second major cultural transition was the change from Neolithic to Bronze Age, taking place around 4000 radiocarbon years ago (c. 4500 cal. BP), and marking the introduction of a more technologically advanced farming society. The replacement of Neolithic populations by immigrating groups accompanied this change (Olalde et al., 2018), after which Bronze Age agriculture and land use expanded under a congenial climate (Tipping, 2005). While the Mesolithic-Neolithic and Neolithic-Early Bronze Age transitions are clearly visible in material culture changes, transformations that occurred in human relations with the land and environment are less so. We present palynological evidence for land-use and environmental changes through the later Mesolithic, Neolithic and Bronze Age on the high-altitude watershed of the Central Pennine hills, probably marginal for early agriculture in terms of climate, soils and vegetation in the mid- to late Holocene (Young, 2000; Young and Simmonds, 1995; Tipping, 2002). The research aims are (a) to investigate the mid- to later Holocene vegetation of this upland, and to establish whether and to what degree its natural vegetation successions were disturbed, and (b) were any disturbances caused by human land use and if so, was early agriculture involved. Three pollen profiles are analysed, providing spatially comparable data for a better understanding of the transitions into and out of the Neolithic. Fine-resolution palynology is used through the pre-Elm Decline levels to study the Mesolithic- Neolithic Transition in detail. Materials and Methods The study area Rishworth Moor is a flat plateau over 400 m above sea level on the watershed of the Central Pennines to the northeast of Manchester (Figure 1). The plateau is covered by shallow blanket peat, with deeper peat in depressions and in channels at spring heads, where older sediments are preserved. Rishworth Moor has been the subject of previous palynological research (Bartley, 1964, 1975). Current vegetation comprises heath plants Calluna vulgaris and other Ericaceae, with Eriophorum vaginatum, Molinia caerulea and Sphagnum spp. in wetter areas. Rarely, wood fragments are present at the base of the peat. The Central Pennines (Figure 1B) contains many archaeological sites (Manby, 1986; Manby et al., 2003; Petch, 1924) and was well exploited by prehistoric communities. Neolithic and 3 Bronze Age sites are mainly located (Figure 1B) on the lower moors although some occur on the