Dating initial Maori environmental impact in New Zealand
Abstract
Over the last decade there has been an intense debate as to whether New Zealand prehistory is ‘long’ (>1500 yr), ‘short’ (<600 yr) or ‘intermediate’ (c.1000 yr). Pollen and charcoal analyses have played a key role in this debate by pinpointing the transition from relatively undisturbed environments to those deforested by anthropogenic fires. We review pollen and stratigraphic studies carried out on a variety of sites, including peat bogs, swamps, estuaries and lakes, and contribute new results. Different sedimentary environments show varying susceptibilities to contamination and have resulted in a wide spread of ages for initial Maori impact. Peat and macrofossils from bogs are the least susceptible to contamination by old or young carbon, whereas lakes and swamps are subject to inwash of old carbon and hard water effects. Silty sediments appear to be particularly vulnerable to contamination. Analysis of 14C dates for the start of Maori deforestation show that ages falling in the ‘long’ prehistory period are exclusively derived from lakes and swamps. In contrast, the bulk of the ages falling in the ‘short’ prehistory period are from bogs. We conclude the first evidence of Maori environmental impact dates to 1200–1400 AD (750–550 calendar years BP). Finer age resolution is limited by the uncertainty associated with identifying the first signs of human impact and variability of the 14C calibration curve.
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