Environmental impacts around the time of Norse landnam in the Qorlortoq valley, Eastern Settlement, Greenland

Palynology, radiocarbon dating, and open-section stratigraphies from archaeological trenches are used to examine the impact of human activity around the time of Norse landnam on vegetation and landscape associated with a small farm (emptyset 34) in the Qorlortoq valley, Eastern Settlement, Greenland (61 degrees N 45 degrees W). Peat deposits from a mire abutting the Norse ruins revealed a discontinuous palaeoenvironmental record containing a possible hiatus from ca. AD 410-1020. Palaeovegetational data were recovered either side of this period. Pollen assemblages suggest that open Salix scrub dominated the landscape during the pre-settlement phase. The later phases of landnam resulted in the creation of hay fields and heavily-grazed grassy heath. Site abandonment is reflected by a re-expansion of Salix. This occurs shortly before the onset of deposition of a Sphagnum peat, dated to cal AD 1420-1630 (2 sigma) and reflecting an increase in mire surface wetness, probably in response to a deteriorating climate. Radiocarbon dates were obtained on peat and plant macrofossils sampled from either side of the proposed hiatus at two different but closely-spaced (<20 m) locations across the mire. These produced significantly different dates for the cessation of peat formation in the pre-landnam period (cal BC 2130-1770 and cal AD 240-410 respectively), but near-synchronous dates for the recommencement of peat growth (cal AD 890-1150 for peat and a probably more reliable interval of cal AD 1020-1190 based on plant macrofossils). It is suggested that this hiatus may represent the first direct evidence for peat cutting in Norse Greenland. (C) 2007 Elsevier Ltd. All rights reserved.