Jane Wheeler

Spheroidal carbonaceous particles are a defining stratigraphic marker for the Anthropocene

There has been recent debate over stratigraphic markers used to demarcate the Anthropocene from the Holocene Epoch. However, many of the proposed markers are found only in limited areas of the world or do not reflect human impacts on the environment. Here we show that spheroidal carbonaceous particles (SCPs), a distinct form of black carbon produced from burning fossil fuels in energy production and heavy industry, provide unambiguous stratigraphic markers of the human activities that have rapidly changed planet Earth over the last century. SCPs are found in terrestrial and marine sediments or ice cores in every continent, including remote areas such as the high Arctic and Antarctica. The rapid increase in SCPs mostly occurs in the mid-twentieth century and is contemporaneous with the ‘Great Acceleration’. It therefore reflects the intensification of fossil fuel usage and can be traced across the globe. We integrate global records of SCPs and propose that the global rapid increase in SCPs in sedimentary records can be used to inform a Global Standard Stratigraphic Age for the Anthropocene. A high-resolution SCP sequence from a lake or peatland may provide the much-needed ‘Golden Spike’ (Global Boundary Stratotype Section and Point).

Charcoal analysis of industrial fuelwood from medieval and early modern iron-working sites in Bilsdale and Rievaulx, North Yorkshire, UK: evidence for species selection and woodland management

Abstract This paper presents the results of species diversity and dendrological analyses of archaeological charcoal excavated from medieval and early modern iron production sites in Bilsdale, and at Rievaulx in the neighbouring valley of Ryedale, North Yorkshire, UK. Standard methods of quantification are used to assess species diversity, sampling sufficiency and taxa presence. The assessment of dendrological features provides additional evidence for growth trends and cutting cycles analogous with cyclical woodland management, as well as environmental and growing conditions. Analysis of archaeological charcoal from four medieval bloomery furnace sites in Bilsdale, and from the site of the hammersmithy and blast furnace at the early modern iron works at Rievaulx, provide comparable data-sets which indicate a change in cutting practise and dominant species selection for industrial fuelwood occurred between the 12th- and mid-16th centuries AD. Results show that dominant species presence changed from an admixture of predominantly birch (Betula sp.) and hazel (Corylus avellana) sourced from small calibre branchwood and stemwood used in the medieval bloomery furnaces, to a dominant oak (Quercus sp.) presence from standard sources used at the Rievaulx iron works by the mid-16th century. Whilst it is uncertain whether this change in dominant species composition and the source of industrial fuelwood is related to changes in local availability, or the result of the technological transition to blast furnace processing which occurred at this time, estate records reveal a woodland management campaign was instigated to supply and maintain fuelwood supplies to the iron works at Rievaulx which coincides with the introduction of Tudor arboricultural legislation in the 1540s.

Vegetation Changes and Woodland Management Associated with a Prehistoric to Medieval Burnt Mound Complex at Ballygawley, Northern Ireland

ABSTRACT This paper examines the impact on woodlands associated with burnt mound use from floodplain sediments and peats, using a combination of pollen, non-pollen palynomorphs, micro- and macro-charcoal and worked wood for the first time. We present this data from a multi-period burnt mound complex, dating from the Late Neolithic to the Medieval period, at Ballygawley, Co. Tyrone, Northern Ireland, to reconstruct vegetation changes from the Neolithic onwards and establish the significance of these changes, in particular on woodlands whilst the burnt mounds were in use. The findings from the macroscopic charcoal suggests the most abundant trees were commonly, but not exclusively, exploited. Local woodland was seemingly unaffected by use of burnt mounds during the Neolithic and early Bronze Age based on pollen evidence. A sustained increase in microscopic charcoal coincides with a permanent decrease in alder-carr woodland during a period of near continuous burnt mound use between 1725 and 530 BC, and a second phase of high microscopic charcoal values, c. AD 880, corresponds to the end of the penultimate phase of burnt mound use. Evidence from the worked wood suggests that some form of woodland management was used for hazel from the Neolithic onwards.