HILL farming is on the brink of a "rapid, and unmanaged collapse," the National Trust warned this week.

If livestock disappeared from the uplands, the landscape and features would change dramatically, with an impact on wildlife and tourism.

In Wednesday's stark warning, the trust said the separation of support payments from agricultural production had already shown upland livestock farming was not profitable and, in many cases, made a loss.

A study of 60 of its tenanted hill farms found the majority faced a severe drop in income. Some would be in the red by next year and most would lose money from livestock by 2012 unless the Government stepped in with urgent help.

The trust looks after 150,000 hectares of land in upland areas but its report said the bleak future involved all hill farms, not just its own.

Under the new system hill farmers do not have to keep livestock to receive their CAP payments.

"There is a real risk that we will lose the grazing animals vital for the management of some of our most spectacular landscapes and wildlife," the report's authors warn. "Some farms will see their support payments halved over the next five years, which could force large numbers to go out of business before they have had the chance to adapt to the reforms."

From the Lake District to the Yorkshire Dales, uplands depended on livestock farming to maintain their character and wildlife. The loss of hill farming would have a severe impact on vast tracts of some of England's most famous landscapes.

The trust wants the Government to introduce effective transition arrangements urgently, to enable hill farmers to adapt to the daunting economic climate. Without rapid help, the tourism and environmental benefits of upland management could be permanently lost.

The report said the uplands should have benefited from CAP reforms, but these had not been accompanied by enough transitional support to enable upland farmers to diversify or to reward them sufficiently for providing environmental and access benefits.

Fiona Reynolds, National Trust director general, said: "The Government needs to recognise fully the public value of upland farming which supports wildlife, maintains a rich and varied landscape, provides access to millions of people and underpins a vibrant tourism industry. Further measures are urgently needed to put upland farming on a more sustainable footing and avoid chaotic change in some of our most cherished landscapes."

David Riddle, director of land use at the National Trust, urged the Government to speed up the introduction of transitional support measures dramatically. These include targeted support for managing the upland environment and providing public access; advice and training to help hill farm businesses adapt, and a review of the preferential support for lowland areas.

* The North-East NFU has written to the Yorkshire Dales, North York Moors and North-umberland National Parks, urging them to join the debate about the future of the Hill Farm Allowance, which NFU regional director, Richard Ellison, says is a lifeline for hill farmers.

The HFA is under review and the NFU has set up a new upland working party to look at how the scheme should be developed for the future.

"Our view is that an adequately-funded replacement HFA scheme is absolutely vital to ensure farmers continue to farm the upland areas in the way they have always done," said Mr Ellison.

"Hill farmers across Yorkshire and the North-East manage more than 1.7m hectares of land, 350,000 of which are in one of the national park areas.

"The stunning landscape that underpins our thriving regional tourism industry is not there by chance; it's there largely due to generations of farming activity. To maintain that, we need upland farming to remain viable.

"I know the national parks are concerned about the impact of any changes to the way our upland areas are managed. We now need them to voice this concern and help us develop a sustainable hill farming sector."