New map produced showing where the world’s major food crops should be grown to maximise yield and minimise environmental impact. Scientists at the University of Cambridge say adopting such a policy would capture large amount of carbon, increase biodiversity and cut agricultural use of freshwater to zero. The reimagined world map of agriculture includes large new farming areas for many major crops around the corn belt in mid-western USA, and below the Sahara. Huge areas of farmland in Europe and India would be restored to natural habitat. Assuming the farming would be mechanised and high-input, the scientists say the redesign would cut the carbon impact of global croplands by 71%, by allowing land to revert to its natural, forested state. This is the equivalent of capturing 20 years’ worth of current net CO2 emissions. In this optimised scenario the impact of crop production on the world’s biodiversity would be reduced by 87%, drastically reducing the extinction risk for many species. Croplands would quickly revert back to their natural state, often recovering their original carbon stocks and biodiversity within a few decades. The redesign would eliminate the need forirrigation altogether; by growing crops in places where rainfall provides all the water they need to grow. Agriculture is currently responsible for around 70% of global freshwater use, and this causes drinking water shortages in many drier parts of the world. The researchers used global maps of the current growing areas of 25 major crops, including wheat, barley and soybean, which together account for over ¾ of croplands worldwide. They developed a mathematical model to look at all possible ways to distribute this cropland across the globe, while maintaining overall production levels for each crop, allowing them to identify the option with the lowest environmental impact.  While a complete global relocation is a step too far, taking a paired down approach and only redistributing croplands within national borders would still result in significant benefits: global carbon impact would be reduced by 59% and biodiversity impact would be 77% lower than at present. A third, even more realistic option of only relocating the worst-offending 25% of croplands nationally would still result in half of the benefits of optimally moving all croplands. The study finds that the optimal distribution of croplands will change very little until the end of the century, irrespective of the specific ways in which the climate might change. The researchers say set-aside schemes that give farmers incentives to retire part of their land for environmental benefits and financial rewards for producers could help.