A dramatic land-clearing surge in Queensland could turn into a “tsunami” in the coming year, say conservationists, the rate of notifications of planned clearing rising 30% in the past year compared with the previous three-year average.

If that translates to a 30% jump in land clearing, Queensland – a region already marked as a global deforestation hotspot – could experience rates of land clearing seen just twice since detailed observations began in the 1980s.

Since July last year, 1,608 properties in Queensland have notified an intention to clear a total of almost 945,755 hectares of land. Almost all of it is “remnant” forest or bushland – a term used to describe forest that hasn’t previously been cleared. There was also an additional 80,200ha of “high-value agriculture” land approved for clearing, making a total of 1.02m hectares of clearing in the pipeline.

If it goes ahead it would undo the work of more than $1bn the federal government has spent paying other landholders not to clear their land, in order to cut carbon emissions under the Coalition’s Direct Action policy.

The number of notifications over the period amounted to almost 115 a month – a roughly 30% increase from the rate of fewer than 90 per month seen in the preceding three years.

Before July 2016, the Queensland government didn’t release the area of land in each clearing notification, so the relative jump in area that is earmarked for clearing cannot be accurately compared.

The rise in planned clearing – which could be a sign of “panic clearing” before a planned crackdown if Labor is re-elected – would also cause a spike in sediment washing onto the Great Barrier Reef, which the United Nations has warned is threatening joint Queensland and federal government plans to improve water quality on the reef.

Only a small fraction of land clearing in Queensland needs to be notified, meaning the actual amount of planned clearing is much larger.

The federal government has been using the $2.55bn Emissions Reduction Fund to pay polluters – mostly potential land clearers – not to clear. In the most recent auction, the government paid $11.82 for each tonne of CO2-equivalent of greenhouse gasses that were abated.

The more than 1m ha of land earmarked for clearing would result in more than 90m tonnes of greenhouse gas emissions. That means the earmarked clearing would wipe out more than $1bn worth of carbon abatement.

“There’s a tsunami of deforestation hitting Queensland right now,” said Wilderness Society Queensland campaign manager Gemma Plesman. “It’s insane that nearly 1m hectares has been targeted for clearing from July 2016 to September 2017 or already has been cleared. That’s an annual rate of 830,000ha – that’s twice as much as the record 395,000ha cleared in 2015-16.”

The figures come amid an election campaign in which tree-clearing policy has been marked as a key point of difference between the parties. In their current term of government, Labor attempted to pass legislation to stop the surge caused by the previous LNP government, but failed to get the numbers. The premier, Annastacia Palaszczuk, has taken a policy to the election that intends to stop the runaway deforestation, a pledge that has been applauded by conservation groups.

Plesman said: “The LNP, which started this free-for-all, wants this madness to continue, while One Nation’s policy is even worse. It’s only the Labor party and the Greens that want to stop this lunacy.”

Two thirds of the proposed clearing is being done under contentious rules over “thinning”, which allow clearing of 75% of the trees on a site without approval.

The news comes a month after Queensland released its annual satellite monitoring report, showing that clearing in 2015-16 jumped 33% compared with the previous year.

At the time, the environment minister, Steven Miles, said the report was “nothing short of devastating” because of the effects on wildlife, reef waters and coral, and Australia’s carbon emissions.

WWF Australia found that clearing would have killed nearly 45m animals. According to a study published in the journal Nature in October, Australia is the second-worst country for species loss.

Plesman said: “Deforestation in Queensland is a national disgrace. Queensland now ranks alongside the Amazon, Borneo and the Congo as a world top 10 deforestation hotspot, and will likely move further up that unwanted ladder if this proposed clearing takes place.”