London (CNN)Up to one quarter of UK land would be left to nature if a new plan to reduce the country's carbon emissions were introduced.
The proposal comes in a report from environmental group Rewilding Britain, which recommends restoring and protecting woodlands, peatbog, heaths and grasslands as a way to naturally absorb CO2 from the atmosphere.
It targets a total of more than 6 million hectares of land for the scheme, which its says could remove 47 million tons of CO2 from the atmosphere each year -- more than a tenth of current UK emissions.
It estimates the cost at £1.9 billion ($2.4 billion) a year, and suggests a new subsidy system could pay landowners to restore ecosystems and increase carbon sequestration.
"Our report demonstrates how land use change with nature at its heart can play a major role in our efforts to meet our targets and address climate breakdown," said Rewilding Britain chief executive Rebecca Wrigley, in a statement.
"We want the government to use the increasing sense of urgency as an opportunity to radically review how land is managed in the UK."
A spokesperson for the UK Department for Environment, Food and Rural Affairs said that "climate change is one of the most urgent and pressing challenges we face today."
They added, "Paying land managers to restore natural ecosystems such as peatland and woodland will make an important contribution to climate change mitigation. It is also a key part of our long-term vision for a more productive, low-carbon farming sector."
One million urban trees
On Sunday, the UK government announced a £10 million ($12.7 million) plan to plant 130,000 trees in English towns and cities, part of a target to plant one million urban trees by 2022.
Earlier this month Lawmakers in the UK Parliament declared an environment and climate emergency, making it the first country in the world to do so.
A day later the government's chief advisory committee on climate change said the UK should aim to cut its greenhouse gas emissions to net zero by 2050.
If adopted, the target would be the most ambitious emissions reduction goal set by any large economy.
Scientists believe that restoring natural carbon-absorbing "sinks" such as forests can play an important role in limiting climate change.
Tom Crowther, a climate change ecologist at Swiss university ETH Zurich, has calculated there is enough room on the planet for 1.2 trillion new trees -- and that planting them could be the single most effective way of removing CO2 from the atmosphere.