After the fire: can our plants bounce back?

There is also division on what humans could or should do to assist ecosystems as they recover in a period of drought and climate change.

Fire is not always a negative for Australia's landscapes. Parts of Australia's bush are pyrophytic - meaning a plant specie can resist and even thrive after fire, and Indigenous land-management practices over tens of thousands of years have involved regularly burning parts of the bush to prevent bigger, more destructive fires.

But the strain put on many areas of Australia's ecosystems by prolonged drought, and repeated fires, mean experts say just how parts of the bush will regenerate are yet to be seen.

"All of them [ecosystems] will regenerate in some form after the fires," said Dan Metcalfe, deputy director of land and water at the CSIRO.

"The interesting question is what regenerates."

According to Dr Metcalfe, who is part of the expert panel advising Environment Minister Sussan Ley on how to support and assist the recovery of native plants and animals after the fires, those answers won't become clear until the end of the bushfire season.

"Some of these fires have been incredibly intense, have been very large in scale, and have burned the entire landscape. And there are other areas that have been protected or haven't burned," Dr Metcalfe said.

"They might provide refugia for seeds or for seed-dispersing animals that might help to recolonise areas that have been burned. Until we know what's left at the end of the fire season, we don't know how extensive those reserves are and whether they will be able to get back into areas that have been burned."

The intensity of the fires and the dryness of the landscape due to drought mean it is yet to be seen if plants react in the way they may have previously been expected to.

"Are we looking at fires that are more intense and hotter than we would normally see? And if they are hotter, does that mean that they're overwhelming the kind of plant defences that are normally appropriate?

"Are they penetrating the wood and killing off the buds? Are they cooking the seeds that should be the next generation because the intensity of the fire is greater? We really don't know the answer to that yet."

While many Australians are grieving over the loss of homes and wildlife, Professor David Bowman at the University of Tasmania is grieving for the loss of ecosystems, particularly for the high country, which he believes is exhausted after being burnt too soon after previous fires, starting a "downward spiral".

"What this means is that the quality of the habitat will change, there will be fewer trees. Eucalypts are a keystone species. So there'll be less blossom, so that'll have knock on effects - there'll be fewer insects which will have knock on effects for birds and other animals. It'll change the land surface. It'll change the soils. It'll change the hydrology"

Professor Bowman, who is an expert in the relationship between fire, landscapes and humans, says drought has reduced the ability of trees to bounce back after fires, and climate change will also affect the regeneration process.

"Even the plants that regenerate, because of climate change, they're going to grow slower, which means that they're storing less carbon and they're more likely to be burned again. So we're in a really precipitous situation."

These fires could be a mortal blow for some trees, he said.

"Although those amazing strategies exist and make eucalypts some of the most fire resistant plants on Earth, they do have chinks in their armour. And unfortunately, with climate change, and the fires we're seeing, we're now seeing those chinks getting widened, and those chinks are possibly so wide that unfortunately, some of the forests have been stabbed in the heart and they will die."

Radical action may be needed to preserve landscapes, Professor Bowman said, making a proposal he believes won't be accepted by many in the sector - humans becoming more interventionist when it comes to fire-proofing the landscape.

"One idea is to take seeds from one environment, electively, a drier environment, or warmer, drier environment and electively sow them to try to fireproof, by giving the right species a chance to grow more quickly and to develop greater fire resilience, that's an extremely radical proposition," Professor Bowman said.

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Action also needs to be taken to prevent invasive plants and feral animals like rabbits, goats and horses from impeding recovery, says Lucy Commander, project manager at the Australian Network for Plant Conservation.

Dr Commander has also called for the government's $50 million fund for wildlife and plant recovery to be spent strategically, instead of rushing in.

"It's really important to note, ecosystems and plant communities are really complex. They may have species and interaction with species we don't know about yet," Dr Commander said.

"Before rushing out there and having any hasty efforts, it's a good point to step back and make a proper strategic plan - what's the goals of restoration, what do you want it to look like?"

While emphasising that every ecosystem is different and that there won't be one overall solution that could be applied across Australia, Dr Commander said some areas will need to be left alone.

"In some cases it may be better to not have people walking on the soil because we don't want humans trampling, or going and riding in on bikes, to make sure the soil can stay intact to be able to regenerate."

Strategic decisions also need to be made around how species are protected and assisted, Dr Commander says, including how seeds are collected. But the universal message, is that there is no universal answer when it comes to assisting ecosystems to regenerate after fires.

"It's different in every situation: it depends on fire history, it depends of the level of degradation, whether the ecosystem is intact ... the land managers need to work on a case by case basis."