New Late Holocene Palaeoenvironmental Records from Loonan and Blythemo, Mainland, Orkney

New Late Holocene palaeoenvironmental records from Loonan and Blythemo, Mainland, Orkney A thesis submitted to the University of Manchester for the degree of Master of Philosophy in the Faculty of Humanities August 2016 Geneviève Marie Potts School of Environment, Education and Development LIST OF CONTENTS List Of Figures 5 List Of Tables 6 Abstract 7 Declaration 8 Copyright Statement 8 Acknowledgements 9 Chapter 1 – Introduction 1.1 Background 10 1.2 Importance Of This Research 11 Chapter 2 – Regional Context 2.1 Introduction 12 2.2 Physical Description of Orkney 12 2.3 Orkney Climate 13 2.4 Solid Geology 16 2.5 Quaternary Glaciations 19 2.6 Superficial deposits 22 2.7 Holocene Sea Level change 23 2.8 Modern vegetation and land use 24 2.9 Archaeological background of Orkney 26 2.10 Previous paleoecological research on Orkney 32 2.10.1 Woodland development on Orkney 32 2.10.2 Removal of the woodland 35 2.10.3 The development of the heathland communities 36 2.10.4 The impact of Iron age and later societies 36 2.10.5 Shetland 37 2.10.6 North West Scotland 38 2.11 Importance of the research and research aims 39 2 2.12 Site identification 40 2.12.1 Site 1: Loonan 43 2.12.2 Site 2: Blythemo 46 2.13 Conclusions 48 Chapter 3 – Methods 3.1 Introduction 50 3.2 Rationale 50 3.3 Modern climatic data 52 3.4 Field methods 53 3.5 Sampling and storage 55 3.6 Background of methods 56 3.6.1 Peat 56 3.7 Laboratory methods 58 3.7.1 Humification 58 3.7.2 Pollen analysis 61 3.7.3 Charcoal 65 3.7.4 Geochemistry 66 3.7.5 Dating methods 68 3.8 Conclusion 70 Chapter 4 – Results 4.1 Introduction 71 4.2 Peat stratigraphy 71 4.2.1 Loonan 71 4.2.2 Blythemo 72 4.3 Age depth curves and dates 72 4.4 Loonan pollen and geochemistry 80 4.5 Blythemo pollen and geochemistry 86 Chapter 5 –Discussion 3 5.1 Introduction 92 5.2 Interpretation of pollen and charcoal 92 5.2.1 Loonan 92 5.2.2 Blythemo 95 5.3 Interpretation of geochemistry 98 5.4 Overall interpretation 101 5.4.1 Loonan interpretation 102 5.4.2 Blythemo interpretation 103 5.5 Summary of influences to climate change 103 Chapter 6 – Conclusion 6.1 Overview 105 References 108 Word Count: 21,213 4 LIST OF FIGURES Figure 2.1 The position of Orkney and the arrangement of the archipelago 13 Figure 2.2 Ocean circulation map 15 Figure 2.3 Wind speed map around Scotland 16 Figure 2.4 Solid and drift map 18 Figure 2.5 Geology of Orkney 19 Figure 2.6 Glacial Evidence on Orkney 20 Figure 2.7 Superficial deposits 22 Figure 2.8 Holocene isobase models for Orkney 24 Figure 2.9 Neolithic timeline 28 Figure 2.10 Vegetation succession described by Bunting (1996) 34 Figure 2.11 General location map. 41 Figure 2.12 Locality of Loonan and Blythemo, North Mainland 43 Figure 2.13 Sitemap Loonan 44 Figure 2.14 View North across the site. Area where core was collected 44 Figure 2.15 Typical vegetation at Loonan with dip wells 45 Figure 2.16 Site map of Blythemo 46 Figure 2.17 View North East across the site. Area where core was collected 47 Figure 2.18 Typical vegetation at Blythemo 48 Figure 3.1 Climate Summary from 1995-2015 53 Figure 3.2 Diagram of energy flow in a mire ecosystem 56 Figure 4.1 Loonan age depth curve 73 Figure 4.2 Blythemo age depth curve 74 5 Figure 4.3 Loonan pollen profile 76 Figure 5.2 Loonan geochemistry 77 Figure 5.3 Blythemo pollen profile 78 Figure 5.4 Blythemo geochemistry 79 LIST OF TABLES Table 3.1 Elements determined by ICP-OES 66 Table 4.1 Loonan Stratigraphy 71 Table 4.2 Blythemo Stratigraphy 71 Table 4.3 Calibrated age Loonan 73 Table 4.4 Zone boundary age Loonan 73 Table 4.5 Calibrated age Blythemo 74 Table 4.6 Zone boundary age Blythemo 75 6 ABSTRACT The University of Manchester, Geneviève Marie Potts, M.phil New Late Holocene palaeoenvironmental records from Loonan and Blythemo, Mainland, Orkney. August, 2016 The Orkney Islands have been the subject of many archaeological studies but few studies have attempted to reconstruct the past environment of the Islands. Following palaeoenvironmental reconstructions previously undertaken on parts of the Orkney Mainland (Moar, 1969; Bunting, 1994, 1996). The aim of this project is to reconstruct past environment using multiproxy techniques, a study area in the critical region is required, and a technique of reconstruction known to produce replicable and accurate palaeoclimatic data. The peat cores collected from two sites on North mainland Orkney were prepared for pollen analysis, and also peat humification to add finer resolution to the results obtained. Peat geochemistry will also be used as a potential palaeoclimatic indicator (Biester, et al. 2003). Cores will be dated using radiocarbon dating. The profile from Loonan was dated from c. 2692 BP and Blythemo c.3689 BP, from this age depth models and pollen assemblages were found to show the a multiproxy analysis of these sample sets from Orkney. Some similarities were found between Bunting (1994) in relation to Bronze age and Iron age influences. More extensive work with better preservation of pollen would aid a conclusion to accurate palaeoclimate records on these site on Orkney. 7 DECLARATION No portion of the work referred to in the thesis has been submitted in support of an application for another degree or qualification of this or any other university or other institute of learning. COPYRIGHT STATEMENT i. The author of this thesis (including any appendices and/or schedules to this thesis) owns certain copyright or related rights in it (the “Copyright”) and s/he has given The University of Manchester certain rights to use such Copyright, including for administrative purposes. ii. Copies of this thesis, either in full or in extracts and whether in hard or electronic copy, may be made only in accordance with the Copyright, Designs and Patents Act 1988 (as amended) and regulations issued under it or, where appropriate, in accordance with licensing agreements which the University has from time to time. This page must form part of any such copies made. iii. The ownership of certain Copyright, patents, designs, trade marks and other intellectual property (the “Intellectual Property”) and any reproductions of copyright works in the thesis, for example graphs and tables (“Reproductions”), which may be described in this thesis, may not be owned by the author and may be owned by third parties. Such Intellectual Property and Reproductions cannot and must not be made available for use without the prior written permission of the owner(s) of the relevant Intellectual Property and/or Reproductions. 8 iv. Further information on the conditions under which disclosure, publication and commercialisation of this thesis, the Copyright and any Intellectual Property and/or Reproductions described in it may take place is available in the University IP Policy (see http://documents.manchester.ac.uk/DocuInfo.aspx?DocID=487), in any relevant Thesis restriction declarations deposited in the University Library, The University Library’s regulations (see http://www.manchester.ac.uk/library/aboutus/regulations) and in The University’s policy on Presentation of Theses. ACKNOWLEDGEMENTS I would firstly like to thank the SEED for a grant in my second year and NERC for awarding funding for the radiocarbon dates both were essential to helping me finance the fieldwork and analysis. Secondly, many thanks to Jeff Blackford and Pete Ryan for their guidance, humour and understanding and help with fieldwork visits. Also thanks to the invaluable laboratory staff John and JY for assistance during preps. Rosie Wilkinson also provided support and encouragement during this work, so thank you also. Finally, many thanks to my husband Lee and also my best friend Lisa for supporting me throughout. And I couldn’t have funded it without Nantwich Swimming Pool being flexible with my working hours allowing me to work around the research, which was greatly appreciated. 9 Chapter 1 - Introduction 1.1 General overview Environments change for a variety of reasons, for example external forces, such as climate change or cosmic bombardment and internal forces, such as human activities, edaphic change, geomorphic change, and tectonic activity. This thesis is concerned with environmental change on Orkney; in particular the significance of climatic change and the impact of past human populations on the Orcadian environment. The response of human populations to the changing environment is also considered. ‘Palaeoecology is the investigation of individuals, populations, and communities of ancient organisms and their interactions with and dynamic responses to changing environments’ (Gastaldo et al., 1996, pp.10). Palaeoecology uses proxy measures of past ecosystem processes. As such it does not directly measure past ecosystem change but the indirect effect of these changes on the organisms and inorganic components of that system. There are therefore an additional assortment of difficulties in interpreting the palaeoecological data in terms of past ecosystems. However, palaeoecology remains one of the most reliable methods to do this. Increasingly in palaeoecological studies, a multi-proxy approach is adopted. When a number of methods are used in isolation and then combined to show a multi-proxy set of results, more secure palaeoenvironmental interpretations are possible. When reconstructing changes in the environment via proxy records, the degree to which the response and adaptation is caused by variations in one or more of the forces of environmental change outlined above is a subjective assessment (Mortitz and 10 Agudo, 2013).

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