Tackling wildfires key to avoiding mass extinction, UCC study shows

By examining the past, it looks at whether we are currently on a path to a similar mass extinction and whether there are steps that can be taken to avoid another devastating extinction.

The team from UCC, along with the Swedish Museum of Natural History, examined the worst mass extinction on Earth, the end-Permian mass extinction.

The event, which took place 252m years ago, eliminated almost every species and saw entire ecosystems collapse.

Research found there was a sharp spike in wildfire activity due to rapid greenhouse gas emissions from volcanoes, extreme warming and drying.

Vast regions that had previously been permanently wet were experiencing wildfires.

Where these wetlands had been capturing carbon from the atmosphere, they became major sources of atmospheric carbon.

Known as 'carbon sinks', these areas naturally and continuously capture carbon from the atmosphere. As the Earth warms, carbon sinks are becoming ever more important as they work to keep heat-trapping gas out of the atmosphere.

As part of the study, which is published in PALAIOS on Thursday, the team studied fossil plant and charcoal records of the Sydney & Bowen in eastern Australia and Antarctica.

Here, they discovered the wetlands has been regularly disturbed by fires in the lead-up to the mass extinction. Over time, the plants evolved a range of fire-coping mechanisms.

However, even with these adapted mechanisms, the severe climate change and peak of fire activity appears to have pushed even these plants over a tipping point.

According to the study, the entire ecosystem was unable to recover for millions of years after this.

"Sifting through the fossil plant records of eastern Australia and Antarctica, we found high abundances of burnt, or charcoalified, plants throughout the late Permian Period," explained Dr Chris Mays, lecturer in palaeontology at UCC and lead author of the study.

"From this high baseline, charcoal abundances reached a prominent peak right at the top of the last Permian coal beds, indicating a major but short-lived increase in wildfires."

Following this end-Permian burnout, Dr Mays said there was low charcoal for the next 3m years during an Early Triassic depression.

In recent years, the increase in large-scale wildfires has resulted in shocking mass animal die-offs in several regions such as California in 2018 and 2020 as well during the Australian wildfires in 2019-2020.

In Ireland, there were 50 large wildfires, each of which damaged at least 30 hectares of land.

At the same time, the warming global climate has led to prolonged droughts and increased wildfire activity in wet habitats including the peat forests of Indonesia and the vast Pantanal wetlands of South America.

Highlighting these recent events, the researchers said these major carbon sinks are crucial in the current fight against climate change.

The records examined by the study show that without the carbon sinks, the world can potentially stay intolerably warm for hundreds of millennia.