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- Moving cropland to ‘better’ locations and allowing the now-abandoned field to move back to its natural state could decrease agriculture’s carbon footprint, according to a new study.
- However, this solution doesn’t account for different intensities of agriculture and the cultural and social consequences of moving crops away.
- The ability to finance and enforce this programme would also vary between rich and poor countries, creating an “uneven sovereignty” in engaging with it.
Kochi: Crops seem like unlikely culprits – but they are one of the main causes of biodiversity decline around the world.
When croplands replace natural habitats, they deplete biodiversity and release sequestered carbon. Crops consume large amounts of freshwater, often year-round. If there are no irrigation canals, farmers often pump out precious groundwater to feed their plantations.
Scientists recently proposed a simple way out – perhaps too simple to be true. According to a study published in March 2022, we could move existing croplands to better locations, where they can be rain-fed for example, and let the now-abandoned fields regenerate back to their ‘natural’ state.
This, according to the study’s authors, could significantly mitigate agriculture’s current impact on our ability to sequester carbon, protect biodiversity and use water more rationally. These changes could in turn help restore large areas of European and Indian farmland.
There is a problem. Farming is a crucial source of livelihood for millions of people. Even if governments financially compensate farmers to move their crops to a different area, there are many complex social and cultural factors at play, anthropologists told The Wire Science.
Disrupting these relationships could impose a cost too high to pay – even to tackle climate change.
Agriculture has drastically altered the map of the wild. In the last 300 years, humans have transformed almost 40% of Earth’s total ice-free surface into agricultural land and settlements, according to one estimate.
People are also consuming more, which means more land has to be brought under agriculture. As a result, researchers have identified cropland expansion and intensification to be one of the major drivers of biodiversity decline, especially in developing countries in the tropics – like India.
In the new study, Robert Beyer, currently with the Potsdam Institute for Climate Impact Research, Germany, and his peers analysed the distribution of 25 major crops – including rice, wheat and barley – that together account for 77% of cropland worldwide. Then they calculated the impact of these farmlands on carbon sequestration, biodiversity and water use.
They developed a mathematical model to incorporate different possible ways to redistribute this cropland across the planet while maintaining the current production levels for each crop.
This model also incorporated gains of different types of agriculture in new locations – from subsistence-level organic farming to fully-mechanised high yield crops.
The result is a map that shows where the world’s major food crops should be grown to maximise yield and minimise environmental impact (including bringing agricultural use of freshwater to zero).
This reimagined crop map for the world assigns new farming areas for many major crops in the mid-western US and below the Sahara desert in particular. In return, it frees up large tracts of farmland in Europe and India.
According to the authors, assuming high-input farming at the new sites, relocating crops this way can help cut carbon sequestration loss by 71%, biodiversity loss by 87% and water loss by 100%. This is the best case scenario, which also requires some cropland to be ‘moved’ across international borders.
But they also found that even partial relocation – within national borders across smaller distances, and without fully optimised management at the new sites – could bring significant benefits.
Tim Newbold, principal research fellow at the division of biosciences, University College London, called the study a “very interesting” theoretical exercise. But one of the “key limitations,” he added, is that it doesn’t address the impact on biodiversity based on how existing farmland is managed.
Specifically, the study calculated the impact of crop production on biodiversity as the difference between the local biodiversity associated with the natural habitat and that associated with the cropland. This does not capture differences in how differently-managed croplands – low v. high intensity especially – support different levels of biodiversity.
Low-intensity croplands often support more biodiversity. Some agricultural landscapes also support more biodiversity (of certain species) than primary forests in some seasons.
For example, in the Great Himalayan National Park in Himachal Pradesh, and its surrounding agricultural fields, scientists found in 2016 that 80% of bird species seen in the primary forest area were also seen in equal or greater abundance in nearby low-intensity agricultural fields. But as agricultural intensity increased, the number of bird species as well as their numbers dropped.
“Farmland that is managed at lower intensity tends to have more biodiversity than high-intensity farmland,” Newbold wrote to The Wire Science. “Incorporating farmland intensity into future estimates of the potential biodiversity benefits of growing crops in different places will be important to get a complete picture.”
A bigger problem with the study arose when experts considered the social and economic implications of redistributing crops. “Relocating farmland has major implications” for people, Beyer, the study coauthor, told The Wire Science. The authors clearly acknowledge this in their paper too.
“The authors’ acknowledgment of the importance of financial compensation and consent is important, but we must question how both compensation and consent would be enacted,” Cornell University economic and environmental anthropologist Andrew Lehne Ofstehage said.
This is “relatively straightforward” in countries with private farmland holdings. But in many other countries, land is held by many land users together – or held by the state and leased to farmers, Ofstehage added. In the former, consent is complicated; in the latter, consent bypasses land users completely.
In addition, even if land users and land owners are compensated fairly, relocating people would be “a tremendous process,” he added. “Relocation for some is synonymous with progress, betterment and improvement, but for many it is a violent and alienating disconnection from community, memory and social life.”
According to Ofstehage, the ability of such a programme to meet different food tastes and cultures and the logistical challenges of delivering food will be questionable as well.
“Food is culturally defined in terms of optimal tastes and cultural preferences, but even discounting what might be called food preferences, differences in what is even considered edible (e.g. insects, pork, corn fungus or soybeans) limit the degree to which centralised food production can deliver something that is locally-recognized as ‘food’.”
The ability to finance and enforce this programme would also vary between rich and poor countries, creating an “uneven sovereignty” in engaging with the programme – as would differences in the degree to which citizens have a say in how they participate in it, he added.
“Authoritarian countries, for example, could more easily and perhaps efficiently implement an agricultural relocation program, without consent or input from people who live on and work the land.”
Ultimately, climate solutions will be more feasible if they find ways to reduce carbon emissions without undermining the cultural, political and social aspects of human life.