Interpreting charcoal in New Zealand's palaeoenvironment - What do those charcoal fragments really tell us?

The role of charcoal as a palaeoenvironmental indicator has never been fully or adequately explained. Charcoal fragments are often interpreted as evidence for natural fires caused by lightning strike during drought or dry climatic conditions. Generally, no evidence is presented to show this to be the case. The frequency of lightning strike in New Zealand is not high and the extent to which it is a causal factor in generating forest fire is questioned. The assumption is often made that charcoal fragments found in sedimentary deposits are local, or at least reasonably local, in origin. This assumption is being challenged. Fine charcoal fragments appear to be transported regionally within New Zealand. It is highly likely that fine charcoal fragments are being transported from Australia, both by thermal convection during fires and during dust storm events, to be deposited into New Zealand sediments. The consequences of this in interpreting New Zealand's palaeo-history requires researchers to, at the very least, provide charcoal counts within size parameters. This is particularly so for archaeologists who would definitely need to show the presence of large charcoal fragments before interpreting the possibility of people in the landscape. (c) 2008 Elsevier Ltd and INQUA. All rights reserved.