The world must find new ways to feed its booming global population, or face crippling supply shortages that could lead to suffering and severe price spikes, scientists warn.
A global study has found the health and environmental benefits of transforming farming would outweigh the cost of doing so.
The authors of the international report also urge governments to do more to support sustainable agriculture.
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A global study has found the health and environmental benefits of transforming farming would outweigh the cost of doing so and could present a long-term solution to the issue of feeding a world with a swelling population whilst in the grip of a climate crisis (stock)
'A small disruption in supply really can do a lot of damage and leads to huge price increases,' said Per Pharo of the Food and Land Use Coalition, the global alliance of economists and scientists behind the study.
'That creates suffering and social unrest. And it will highly likely also lead to hunger and instability,' he told the Thomson Reuters Foundation.
It found that only one per cent of the $700bn (£560bn) a year given to farmers is used to benefit the environment.
Much of the total instead promotes high-emission cattle production, forest destruction and pollution from the overuse of fertiliser.
Global over-dependence on a relatively small number of staple foods leaves populations vulnerable to crop failures, it revealed.
And climate change is adding to the strain and making the current situation untenable.
'Four different crops provide 60 per cent of our calories - wheat, rice, maize and potatoes.
'That increases our vulnerability,' said Mr Pharo, the director of the International Climate and Forest Initiative for the Norwegian Government.
The report is being hailed as the first of its kind to assess the benefits of transforming global food systems as well as the cost of inaction.
The damage the modern food industry does to human health, development and the environment costs the world $12 trillion a year - equivalent to China's GDP - the study found.
The report proposes a series of solutions, from encouraging more diverse diets to improve health and reduce dependency on specific crops, to giving more support to the types of farming that can restore forests, a key tool in fighting climate change
It proposes a series of solutions, from encouraging more diverse diets to improve health and reduce dependency on specific crops, to giving more support to the types of farming that can restore forests, a key tool in fighting climate change.
In Costa Rica, for example, the government has reversed deforestation by eliminating cattle subsidies and introducing payments to farmers who manage their land sustainably.
As a result, the amount of forest cover has risen from a quarter of the country's land in 1983 to more than half today, the report said.
The cost of the reforms it lays out are estimated to be up to $350 billion a year. But that would create business opportunities worth up to $4.5 trillion - a 15-fold return.
The study said the reforms could also free up 1.2 billion hectares of agricultural land for restoration, an integral part of efforts to curb climate change and halt biodiversity loss.
That is more than twice the size of the Amazon rainforest, which spans seven nations.
'What we're saying is realistic if the reform agenda is implemented,' said Pharo, adding that under the proposed changes, consumers would actually get 'slightly more affordable food'.
'The excuse that we cannot prioritise environment at the same time because we've got to focus on development, on human welfare, is simply false. We can deliver both.'
WHAT DO EXPERTS PREDICT FOR THE FATE OF THE PLANET'S PLANTS AND ANIMALS?
Nature is in more trouble now than at any time in human history with extinction looming over one million species of plants and animals, experts say.
That's the key finding of the United Nations' (UN) first comprehensive report on biodiversity - the variety of plant and animal life in the world or in a particular habitat.
Many of the worst effects can be prevented by changing the way we grow food, produce energy, deal with climate change and dispose of waste, the report said.
The report's 39-page summary highlighted five ways people are reducing biodiversity:
- Turning forests, grasslands and other areas into farms, cities and other developments. The habitat loss leaves plants and animals homeless. About three-quarters of Earth's land, two-thirds of its oceans and 85% of crucial wetlands have been severely altered or lost, making it harder for species to survive, the report said.
- Overfishing the world's oceans. A third of the world's fish stocks are overfished.
- Permitting climate change from the burning of fossil fuels to make it too hot, wet or dry for some species to survive. Almost half of the world's land mammals - not including bats - and nearly a quarter of the birds have already had their habitats hit hard by global warming.
- Polluting land and water. Every year, 300 to 400 million tons of heavy metals, solvents and toxic sludge are dumped into the world's waters.
- Allowing invasive species to crowd out native plants and animals. The number of invasive alien species per country has risen 70 per cent since 1970, with one species of bacteria threatening nearly 400 amphibian species.