One of the most interesting science news stories to catch my eye recently is research indicating that the planet may be reaching peak farmland. At first brush, it sounds like bad news, that we are running out of land suitable for growing food to feed our growing global population. Like peak oil refers to when we max out oil production- the point when we start running out.
However, as I dug into this story, I realized that the “peak farmland” the scholars think we are approaching is the maximum peak of our farmed land use, not because we are running out of available land, but because our need for more land is decreasing. Really? The graphs say yes.
The graph above is from “Peak Farmland and the Prospect for Land Sparing,” a chapter in Population and Development Review, by Jesse H. Ausubel, Iddo K. WernicK, and Paul E. Waggoner. This graph pretty much sums up their argument. The amount of farmland needed to produce enough food to feed the planet’s growing population is not increasing in step with the increasing demand. In fact, as this chart, and others in the report, show that food production is rising without the need for more land resources. The authors see this as a positive opportunity for natural landscapes to remain natural-
Expecting that more and richer people will demand more from the land, cultivating wider fields, logging more forests, and pressing nature, comes naturally. The past half-century of disciplined and dematerializing demand and more intense and efficient land use encourage a rational hope that humanity’s pressure will not overwhelm nature.
I came across this paper in a post on Andy Revkin’s Dot Earth Blog at the NYTimes. It caught my eye once I discovered it was a potential bit of good news amidst usual doom and gloom about global food security, especially in the face of changing climate. Global demand for food is projected to continue to increase for some time, even if the rate of population growth continues to slow because increasing affluence also increases caloric consumption. Basically, rich people tend to eat more meat, and it takes a lot more grain to feed a cow to feed a person than it would just take to feed that person. But increasing affluence in countries with a strong vegetarian tradition, like India, don’t exact the same demand on the food supply as increased affluence in a country that eats more meat, like China or the U.S. However, despite still growing population and increasing wealth, the amount of land in agricultural production globally does not appear to be increasing significantly. Ausubel et al argue that agricultural yield began to increase, independent from farmed acreage decades ago thanks to advances in technology.
Between the 1860s and 2010, the population of the United States grew nine times. Income, as measured by GDP, grew 130 times. Corn production in the united States rose 17-fold from 1866 to 2010 (US Bureau of the Census 1975 and 2012). Yet, more land was planted with corn in 1925 than in 2010.
The bright side of this research suggests that deforestation should slow if we have enough agricultural land available, and more natural landscapes can be preserved. However, their work also raises all kinds of what ifs. Will changes in climate or water availability reduce the productivity of our current agricultural acreage? Will technological advances that have increased yields over recent decades continue to improve, or will we reach a limit of land productivity? A big concern the authors raise is biofuels. Pulling agricultural land away from food production to biofuel production could lead to significant increased need for more farmland or pressure against food production.
Ausubel also tells Revkin that this pattern of increased yields reducing the land required to meet population needs are not playing out evenly across the globe. India and China are feeding more people, and more rich people, on fairly consistent acreage, but in Indonesia, deforestation is still proceeding rapidly. Increased agricultural efficiency is not making land conservation obsolete yet, but it’s interesting to think about how it could help. The planet continue to face significant problems with food distribution, considering that the FAO reports that 870 million people, 1 of every 8 humans, is chronically undernourished. Feeding the world remains a challenge. But this research suggests that meeting the world’s food needs doesn’t have to be entirely at odds with the goals of land conservation too.