Farming within Earth's limits is still possible—but it will take a Herculean effort

Gaby Clark
scientific editor

Andrew Zinin
lead editor

The way we currently produce and consume food takes a big toll on the environment.
Worldwide, farming is responsible for of greenhouse gas emissions and uses of all fresh water taken from rivers, lakes and groundwater. It's the leading driver of and , largely from fertilizer run-off. All of these pose a serious threat to ecosystems.
If this sounds serious, it's because it is. If emissions and land clearing trends continue, the world's food system alone could make it impossible to . If we continue eating and producing food in the same way we are now, we will exceed crucial environmental limits by 2050.
What can be done? In our published in One Earth, we looked for ways to keep the food system within environmental limits by 2050. We found only one approach worked: combine high-impact changes such as shifting to flexitarian (low meat) diets, improving farming practices and reducing food waste.
Why will farming take us past environmental limits?
Environmental limits are also known as . These nine boundaries are Earth's natural safety limits. They range from freshwater resources to the biosphere to the climate. Human activities have pushed past six out of nine safe boundaries through clearing too much land, overusing water for irrigation, overapplying fertilizers or emitting more than our permits.
If we cross these thresholds, we risk dangerous and irreversible changes to the conditions supporting a stable planet.
Transforming the way we farm and eat is essential if we are to keep humanity in a within environmental limits.
What does this transformation look like?
The challenge of making food production sustainable is long-running. has compared the effectiveness of different changes authorities and consumers could make. But most studies used different models, making it hard to compare changes.
To overcome this problem, we synthesized information from previous studies and built a database of thousands of future food system scenarios and possible changes. Then we performed a to combine data from multiple studies and draw more robust conclusions.
This approach allows policymakers and researchers to compare apples and apples, as well as see which combination of changes would let us stay within crucial safety limits by 2050.
We focused on four vital indicators: how much land and water is used for farming; the amount of greenhouse gases emitted; and the flows of two key nutrients, nitrogen and phosphorus.
What works best?
What stood out was the sheer variation in effectiveness. Some changes would work very well across several areas, while others would take a lot of effort for not enough result.
Two changes punch well above their weight on land, water and emissions.
The first is with fewer foods sourced from animals. This is similar to traditional regional diets such as the and diets, where meat and dairy are eaten in much smaller proportions compared to whole grains, fruits, vegetables, nuts and legumes.
Returning to this diet could shrink how much land we use for farming by almost a quarter (24%), cut water demand by 14% and slash greenhouse gas emissions by 47%.
The second is . Livestock today are much better at converting their feed into meat or milk than their precursors. But this could be better still. More productive animals could enable an 18% reduction in land use, a 10% drop in water use and a 34% cut to emissions.
Modern fertilizers have made it possible to produce many more crops and fodder. But if too much fertilizer is applied, it can wash off after rain and .
Better timed and more precise application of fertilizer is by far the best way to cut nutrient pollution. Major improvements here could cut nitrogen pollution by 39% and phosphorus pollution by 42%. As a side benefit, it could save farmers money.
Increasing crop yields, lowering agricultural emissions through better soil management and other practices, and taking up technologies such as can significantly reduce our risk of exceeding environmental limits. So too can cutting food waste and using water more wisely in farming. Our show the relative benefits of ten possible interventions and all their combinations.
There is no silver bullet
We found no single change was up to the task of making food production and consumption sustainable.
We considered over a million possible combinations of changes. Of these combinations, only a tiny fraction—0.02%—give us a fighting chance of staying within all environmental limits.
In almost all successful combinations, the world would need to make significant cuts to how many calories come from animals, make big improvements to fertilizer use and nutrient management, and focus research and development on finding ways to farm land and livestock with less resources and emissions.
Most successful combinations also rely on halving food waste and reducing overconsumption.
Is it still possible?
Farming within the limits of Earth's systems will be hard. But it is possible.
Some work is already being done. Global organizations such as the United Nations are making a to accelerate changes to food systems across many countries.
Research like ours can make people feel powerless. But individual change is . Reducing your intake of animal products benefits and the planet.
Properly addressing these very real issues will take concerted, collective work. If we don't succeed, we risk triggering —and threatening the foundation for human civilization.
The knowledge and tools are at hand. What's needed now is ambition—and a sense of what's at stake.
More information: Michalis Hadjikakou et al, Ambitious food system interventions required to mitigate the risk of exceeding Earth's environmental limits, One Earth (2025).
Journal information: One Earth
Provided by The Conversation
This article is republished from under a Creative Commons license. Read the .