Agriculture is responsible for massive carbon emissions and biodiversity loss, but it doesn’t have to be. By simply moving production from certain areas to others, we could not only maximize yields, but also minimize environmental impacts. The benefits of doing so would include much lower carbon emissions, increased biodiversity and less use of fresh water.
That’s according to scientists at the University of Cambridge who have developed a mathematical model to examine where farmland for growing 25 major crops around the world should ideally be located to have the least environmental impact.
Based on their findings, they have produced a new global map of intensive agriculture in which they propose establishing new cultivation areas for important crops in the American Midwest and beneath the Sahara Desert, while simultaneously restoring large areas of agricultural land in Europe. and India to natural habitats.
This change could reduce global carbon emissions from agricultural production by 71% by allowing much of the land currently in use to return to natural forest. “This is equivalent to capturing twenty years’ worth of our current net CO2 emissions. Trees capture carbon as they grow, and they also allow the soil to capture more carbon than when crops are grown there.
Equally important, the impacts of agricultural production on biodiversity worldwide would be reduced by 87%, giving many endangered species plenty of extra room.
The dependence of agricultural production on freshwater, which currently accounts for around 70% of global freshwater use, would also be significantly reduced as crops would be grown in places where rainfall already provides all the water it needs. they need to grow without the need for irrigation.
Does it all sound too good to be true? It shouldn’t, say the scientists.
“In many places, farmland has replaced natural habitat that held a lot of carbon and biodiversity, and crops don’t even grow very well there. If we allowed these places to regenerate and move production to more suitable areas, we would see environmental benefits very quickly”, explains Robert Beyer, a former researcher in the Department of Zoology at the University of Cambridge who now works at Climate Impact Research Institute, Potsdam, Germany.
By contrast, relocating all the world’s farmland to more ideal locations is unlikely, Beyer acknowledges. “It’s currently unrealistic to implement this whole overhaul,” he says. “But even if we moved just a fraction of the world’s farmland out of the way, focusing on the least efficient places for farming, the environmental benefits would be enormous.”
One of the reasons scientists’ models could and should inform policy is that they highlight agricultural areas that are highly unproductive, but which could become hotspots for biodiversity and carbon storage. This would be the case even if only part of the farmland were moved.
“Taking a narrow approach and redistributing farmland only within national borders, rather than globally, would still bring significant benefits: the global carbon impact would be reduced by 59% and the impact on biodiversity would be 77% lower than it is today,” the experts said.
“A third, even more realistic option of moving only the 25% of the most damaging farmland nationwide would yield half the benefits of optimally moving all farmland,” they add.
Reducing the environmental footprint of agriculture
It is important to note that the optimal distribution of cultivated land will remain largely unchanged until the end of the century, even in the face of ongoing climate change. “Optimal growth locations are not a moving target. Areas with low environmental footprints and high crop yields, for today’s climate, will remain largely optimal in the future,” says University of Cambridge scientist Professor Andrea Manica.
Regarding the social, economic and human factors of the relocation of agricultural land, the scientists propose to offer financial incentives to farmers to encourage them to cultivate in places more suitable for these crops in order to reduce environmental impacts.
“The model generated alternative maps of global distribution depending on how the land is cultivated, ranging from advanced and fully mechanized production with high-yielding crop varieties and optimal application of fertilizers and pesticides, to traditional subsistence-based organic farming. Even redistributing less intensive agricultural practices to optimal locations would significantly reduce their carbon and biodiversity impacts.
Many alternative scenarios proposed by other scientists in an effort to reduce the environmental impacts of agriculture have focused on current Western diets. However, such initiatives may well fail, say the scientists behind the Cambridge University study.
“While other studies show that if we shift to more plant-based diets, we could significantly reduce the environmental impacts of agriculture,” they observe, “in reality, diets are not changing rapidly.”
That’s why we must strive to produce the same foods we eat today, but do it more optimally, they add.
By Daniel T. Cross. Articles in English