SCOTTISH scientists believe they have come up with a game-changing farming model which both boosts food output and protects the planet.

World experts have been at loggerheads for years as they try to square conflicting needs to both feed a growing population and stave off catastrophic climate change or species collapse.

Now researchers, in a potentially globally important breakthrough, have modelled a dairy system that produces more milk but still manages to ensure biodiversity.

Scientists, Napier University in Edinburgh and Scotland’s Rural College and the Royal Botanic Gardens at Kew in London, made the breakthrough by tweaking the diets of milking cows.

They found they could grow an optimal diet for cows on farms - using British crops such as rapeseed or oats - in such a way that life-giving and life-sustaining bugs thrived on farmed land.

This marks a dramatic switch from a policy over recent years that saw farmers encouraged to set aside potentially productive land as wild to protect wildlife, especially insects.

Good farming has always meant protecting wildlife, since food production depends on pollinators, such as bees, as well as natural predators and de-composers.

One of the researchers, Patrick White, of Napier University, said: “Until recently a lot of agricultural research has related to an agri-environment type of approach where you are sparing up land to target towards bio-diversity.

“If we are to meet growing consumption we have either got to produce more food on the land we have already got or develop virgin land. So people are starting to look for sustainable development of the land we already farm.”

Scientists found tweaking cow diets from crops grown on farm delivered increases in output - but also that crops they farmed encouraged wildlife, including spiders and specific plants they modelled.

Dr Mark Lee, Research Fellow at Royal Botanic Gardens Kew, added: “With increasing pressure on our finite agricultural land, Sustainable Intensification is important both for local and wider scale biodiversity. Our results highlight a potential route to Sustainable Intensification.”

In recent decades intensification has traditionally been done with the help of chemicals, including those with a high carbon footprint and those which harm wildlife.

In the models developed by the scientists, biodiversity was greatest when spare land was devoted to species-rich grassland.

However, there were also biodiversity gains when the spare land generated in these efficient systems was used for additional crop production.

The greatest gains were achieved when these additional crops supported different species of wildlife, reversing typical trends seen as farms have been intensified around the world.

Dr Lorna Cole, from Scotland’s Rural College, said: “Many agri-environment schemes focus on enhancing biodiversity at a cost to production. Clearly these goals are disparate from those of Sustainable Intensification. Agri-environmental policy needs to take a more holistic approach and there should be greater focus on increasing the efficiency of current agricultural land use and maximising the quality of land taken out of production for biodiversity.”

Dr White said the next step would be to carry out real trials of their system, which is based on data from the Rural College’s Chrichton Royal Farm.

There remains strong support for land to be set aside by farmers for wild biodiversity.

Scottish Greens MSP Mark Ruskell MSP said: “The need to increase biodiversity on our farms is an urgent challenge, and I welcome any research that supports this. However, it’s only part of the problem with our food system right now, and intensification needs to be balanced with addressing climate emissions from land use and livestock, and ensuring the highest possible animal welfare standards.

“We should all be eating less, but better quality, meat and dairy, for both our own health and the health of the planet.

Shifting diets could be just as effective a tool in tackling the environmental impacts of our farming system as ‘sustainable’ intensification.”