Creating more national parks would not only help protect Scotland's natural heritage, but would also be a cost-effective means of providing a major economic boost to fragile rural areas, new research has found.

Two charities, the Scottish Campaign for National Parks (SCNP) and the Association for the Protection of Rural Scotland (APRS), have published the joint study and argue the Scottish Government has broken its 2011 manifesto pledge to "work with communities to explore the creation of new national parks".

At present there are only two parks in Scotland in the Cairngorms and Loch Lomond &The Trossachs, leaving Scotland near the bottom of the world league, the charities say.

They claim that designating more national parks in areas such as the Cheviots or Galloway in the south or north-west Scotland and the island of Harris or Wester Ross in the north west, could generate millions of pounds in extra revenue annually from tourism and other rural industries.

They point to the success of rural areas in other countries such as New Zealand and Norway, where national parks have played a major role in stemming rural depopulation and providing a range of job opportunities.

Ross Anderson, Chairman of SCNP said: "This is the first in a series of research reports we plan to produce. It clearly demonstrates the many positive economic and social benefits that flow from the designation of national parks in fragile rural areas."

He said there was compelling evidence from other countries that national parks stimulate much-needed economic activity to help sustain remoter rural areas. "We urge the Scottish Government to sit up and take notice of our findings", he said.

John Mayhew, Director of APRS said: "National parks have traditionally been recognised as a good way of managing nationally significant landscapes, but this report brings sharply into focus the ways in which national park designation can help to transform the economies of fragile rural areas. "

However a Scottish Government spokeswoman said while the importance of the two existing national parks and the significant contribution they make to conservation, tourism and the wider Scottish economy, was recognised, "The Scottish Government is yet to be convinced that there is a compelling case for the designation of new national parks at this time."