Environmental variability in response to abrupt climatic change during the Last Glacial- Interglacial Transition (16–8 cal. ka BP): evidence from Mainland, Orkney

The Last Glacial-Interglacial Transition (LGIT) is a period of climatic complexity where millennial-scale climatic reorganisation led to changes in ecosystems. Alongside millennial scale changes, centennial-scale climatic events have been observed within records from Greenland and continental Europe. The effects of these abrupt events on landscapes and environments are at present difficult to discern. This in part relates to low temporal resolutions attained by many studies and the sensitivity of palaeoenvironmental proxies to abrupt change. We present a high-resolution palynological and charcoal study of Quoyloo Meadow, Orkney and use the Principal Curve statistical method to assist in revealing biostratigraphic change. The LGIT vegetation succession on Orkney is presented as open grassland and Empetrum heath during the Windermere Interstadial and early Holocene, and open grassland with Artemisia during the Loch Lomond Stadial. However, a further three phases of ecological change, characterised by expansions of open ground flora, are dated to 14.05-13.63, 10.94- 10.8 and 10.2 cal. ka BP. The timing of these changes is constrained by cryptotephra of known age. The paper concludes by comparing Quoyloo Meadow with Crudale Meadow, Orkney, and suggests that both Windermere Interstadial records are incomplete, and that fire is an important landscape control during the early Holocene.