Mid-Holocene charcoal stratigraphy, fire history and palaeoecology at North Gill, North York Moors, UK

Abstract

Small peat mires are a favourable medium for the preservation of charcoal records that can be correlated more precisely with past fire history as part of multi-proxy palaeoecological studies. The North York Moors upland has many suitable peat deposits with a well-researched palaeoenvironmental history that offer the potential for high-precision palaeofire studies. We have examined the charcoal and pollen stratigraphy at the North Gill site at a range of spatial and temporal resolutions for the mid Holocene period between about 7k and 4.5k radiocarbon years ago. In an individual core, three size-class charcoal records, large, small and microscopic, reflect the scale and location of local fire events, although the micro-charcoal curve contains a background regional signal of about 10% of the charcoal/pollen ratio. Most micro-charcoal is generated locally and deposited close to its source. At the site scale, spatial comparison of four cores shows a variable relationship between tree pollen and micro-charcoal concentrations, which is an index of the size and intensity of local fire phases. Individual fires cannot be distinguished. Fine-resolution sampling at the millimetre scale resolves major burning phases into discrete sub-phases that may reflect the effects of individual fires at this fine temporal scale. This multi-scale research indicates that detailed charcoal stratigraphies at varying resolutions are capable of interpretation in terms of local, regional and intermediate fire history.