An Australian engineer is hoping to use drones to plant 1 billion trees every year to fight an unfolding global catastrophe.

Key points: The drone system fires germinated seeds into soil

The drone system fires germinated seeds into soil Drones can plant in areas previously impossible to reach, like steep hills

Drones can plant in areas previously impossible to reach, like steep hills The technology could also help rehabilitate land once used by mines

Deforestation and forest degradation make up 17 per cent of the world's carbon emissions — more than the entire world's transportation sector, according to the United Nations.

Burned or cleared forests release their stored carbon dioxide into the atmosphere, and land restoration experts say technology must play a big part in addressing the problem.

Dr Susan Graham has helped build a drone system that can scan the land, identify ideal places to grow trees, and then fire germinated seeds into the soil.

Drones can plant in areas previously impossible to reach, like steep hills.

The planet loses 15 billion trees every year and much of it is cleared for farmland to feed the world's booming population, but it's feared this could be exacerbating climate change.

"Although we plant about 9 billion trees every year, that leaves a net loss of 6 billion trees," Dr Graham said. "The rate of replanting is just too slow."

Now based in Oxford in the United Kingdom, she is working with an international team including an ex-NASA engineer who worked on the search for life on Mars.

Their company, BioCarbon Engineering, is backed by one of the world's largest drone makers.

The team hopes their technology can help with land restoration around the world. ( ABC News: Dave Maguire )

Industrial-scale reforestation

Bulldozers and tractors can clear land rapidly — and replanting efforts haven't caught up.

Dr Graham is hoping to change that with a system that plants at "10 times the rate of hand planting and at 20 per cent of the cost", she said.

BioCarbon Engineering's CEO Lauren Fletcher said the drone could currently carry 150 seed pods at a time.

"We're firing at one a second, which means a pair of operators will be able to plant nearly 100,000 trees per day — 60 teams like this will get us to a billion trees a year," he said.

Mr Fletcher worked at NASA for two decades on projects including the International Space Station and with robotic technologies used in the exploration of Mars.

"I worked specifically on the intersection between biology and engineering on the life-sciences programs on the Space Station, so this has given me a lot of knowledge of how you take smart, cutting-edge engineering systems and apply it to a biological system," he said.

The firing drone follows a pre-set planting pattern determined from an algorithm, which uses information from a separate scanning drone.

The scanning drone can map an area within minutes. ( ABC News: Jake Sturmer )

To work out the best possible place to plant, the team uses the drone to map the area, looking to create a 3D model of the land.

"The data gets downloaded and we've developed the algorithms that use that data to make smart decisions about exactly where to plant and how to manage that ecosystem," Dr Graham said.

The seed-firing drone follows the team's planting pattern. ( ABC News: Jake Sturmer )

Opportunities to rehabilitate abandoned mines

The team has tested its drone technology around the world and was recently in Dungog, in the New South Wales Hunter region.

This involved trialling their seed-spreading drone to rehabilitate land once used by coal mines.

This drone — while not as efficient as the firing drone — spreads seeds over a far wider area.

"Coal mines have an enormous amount of land that they need to restore, both on the active mine site, once they've recreated a land form, as well as their offset areas ... around the mines," Dr Graham said.

The seed-spreading drone could be used to help restore mine sites. ( ABC News: Giulio Saggin )

"We've had quite a lot of interest in Australia and they see such a benefit in terms of saving cost, saving time, and being able to do a better job of restoring their ecosystems, and getting data to actually show what they've done."

In Dungog, it was tested to see how it performed on a steep hillside.

"Tractors find it very difficult over steep and undulating land," Dr Graham said. "It becomes very dangerous to get a tractor onto a steep hillside.

"However, a drone doesn't matter, it's already in the air, it's already flying the shape of the land."

Finding solutions for depleting farmland

Global research organisation World Resources Institute (WRI) has warned that the amount of arable land is declining.

WRI's Sofia Faruqi said this needed to be turned around in order to produce enough food for everyone on the planet.

"The way we plant trees today is very similar to how we planted them hundreds of years ago," she said.

"So there's major room for innovation in increasing the success rate of tree planting and also in improving the maintenance and monitoring of the restored land."

Seed-planting drones could play a big part in restoring land in a cost-effective way. ( ABC Far North: Mark Rigby, file photo )

Ms Faruqi said around the world there was an area the size of Latin America waiting to be restored — unlocking potentially "massive" benefits.

"People often see planting trees as a feel-good activity but in fact restoration of degraded land has very tangible benefits for all humans," she said.

"Restoring land can provide food for 200 million people. This is because planting trees adds vital nutrients and organic matter into the soil.

"Many of the world's biggest cities rely on forests for their water supply; for example in the US, more than half of drinking water originates in forests, which act like giant sponges.

"Finally ... trees are essential to fight climate change [because] half of a tree's weight is carbon and essentially the trees will dig carbon out of the atmosphere where it's dangerous, and they'll bring it into the soil where it promotes life and vitality."

She added it was important to experiment with technologies such as seed-planting drones to work out the best way to restore land in a cost-effective way.