Rice makes up one out of every five calories eaten around the world. It’s a major food staple for billions of people, and as populations grow, yields of major crops like rice will need to increase in order to feed everyone without further expansion of agricultural land. A recent report released by World Resources Institute estimates the global food supply will have to increase by 56% between 2010 and 2050 to meet projected demand.
But are crop yields growing enough to sustainably feed nearly 10 billion people by 2050?
My colleagues and I at the University of Minnesota calculated how crops performed between 1989 to 2008.
We found that on average, rice yields around the world increased by 1% per year during this period. At this rate, rice production would only increase by about 42% between 2005 and 2050. In many places, this rate of yield improvement would not be enough to meet growing demands without clearing more land for agriculture. But more problematically, there are a few places in the world where rice yields have stagnated or declined.
Where Did Rice Yields Decline?
During the study period (1989 to 2008), yields stopped improving on about a third of rice-producing farms. And on about 1% of farms, yields actually declined. Here are three notable places where rice makes up a substantial portion of people’s diets, but yields declined:
In the Dominican Republic, rice provides about 20% of calories people consume, but yields declined by 0.15% per year between 1989 and 2008.
Nigeria consumed almost 8 million metric tons of rice in 2013, making it the world’s 12th largest consumer of the grain. About 8% of the Nigerian diet comes from rice, but yields in the country decreased more than 3% per year.
About 30% of calories eaten in India are supplied from rice; the country is the second-largest consumer of rice in the world. Overall rice yields in India increased by about 1%, but there are regions within the country that experienced significant declines. In some parts of Maharashtra in central India, yields declined by 7% per year. And to the south in Tamil Nadu, farms saw yield declines of 2% per year.
Without changing course on these historical yield trends, the world may need to clear more land for rice production or risk a shortage. These risks may be higher in areas where yields have stagnated or declined. However, the regions highlighted above may not experience shortages, because trade balances for different countries could change based on fluctuations in crop production.
Yield declines could be due to a number of factors. In a previous study, we noted that stagnating and declining yields could be due to water shortages, declining soil quality, changing temperatures, or a combination of these factors and various socio-economic issues.
You can see the full suite of the maps we developed including maize, wheat, rice, and soybean yield trends from the University of Minnesota’s EarthStat on Resource Watch.