Scientists find record of early Māori land-burning in Antarctic ice

Smoke from last year's Australian bush fires caused this eerie scene over the cleared maunga of Maungakiekie / One Tree Hill. Photo / Greg Bowker

Researchers studying Antarctic ice have discovered evidence that early Māori land-burning caused a major rise in carbon emissions 700 years ago.

The findings, reported in the journal Nature, cast light on the significant changes made to the New Zealand landscape by human settlement, but the findings have been questioned by a Māori academic.

Scientists from the British Antarctic Survey made the discovery when examining ice-core samples taken from James Ross Island in Antarctica.

They found that levels of black carbon, or soot, began to increase dramatically about 700 years ago.

That coincides with the widespread settlement of Aotearoa by Māori.

They compared the samples to others taken from mainland Antarctica and, while soot levels began to grow on the island from 1300, samples from the mainland showed that soot levels there remained stable.

Atmospheric modelling showed the scientists that the soot could have come from either Patagonia, Tasmania or New Zealand.

But it was only here that the charcoal record showed any significant burning around 1300.

Burning forests to clear land has been used by people across the globe for millennia and continued at pace in New Zealand with colonisation, leaving our islands looking startling different between 1000 and 2005.

The scientists were reportedly surprised by the findings, given New Zealand's relatively small landmass, Science Focus reported.

"The idea that humans at this time in history caused such a significant change in atmospheric black carbon through their land clearing activities is quite surprising," said Joe McConnell, research professor of hydrology at Desert Research Institute said.

"We used to think that if you went back a few hundred years you'd be looking at a pristine, pre-industrial world, but it's clear from this study that humans have been impacting the environment over the Southern Ocean and the Antarctica Peninsula for at least the last 700 years."

"Compared to natural burning in places like the Amazon, or Southern Africa, or Australia, you wouldn't expect Māori burning in New Zealand to have a big impact, but it does over the Southern Ocean and the Antarctic Peninsula," said Nathan Chellman, postdoctoral fellow at Desert Research Institute.

At least one Māori academic has pushed back against the research.

In comments published by the Science Media Centre, University of Waikato acting dean of the Faculty of Māori and Indigenous Studies associate professor Sandy Morrison said the study was "devoid of context, devoid of cultural understandings and is yet another example of what we have grown to expect from western science".

"It relies on measurements, modelling and silo thinking and the paper whether intentional or not, posits Māori as the 'naughty' offenders.

"Moreover, it reeks of scientific arrogance with its implicit assumption that somehow Māori have a lot to account for in terms of contributing to carbon emissions and destroying the pristine environment of the Southern Oceans and Antarctica.

"Goodness knows why Māori are primarily emphasised, and for what purpose this article was written."

- Additional reporting, RNZ