Released on 24/12/12

After decades of rapidly  growing global agricultural output, production of four of the world's  most important crops could be stagnating or even slowing in some  regions, according to a new study published in Nature, a top scientific  journal. The study, by the University of Minnesota's Deepak Ray and four  others, examined millions of census reports from the last half century  to gather their data.

The authors are careful  to point out that crop production is still increasing in parts of the  world; it is by no means a categorical decline. The report's abstract  reads summarizes, "Although yields continue to increase in many areas,  we find that across 24 39% of maize-, rice-, wheat- and soybean-growing  areas, yields either never improve, stagnate or collapse." That's about a  quarter to a third of global production of four of our most important  crops.

This is potentially a  very big deal. World populations are still growing. So is the global  middle class, members of which tend to consume more meat and dairy per  person, which means more crops per person. That's been happening for a  while, and it's been fine as long as food production has kept pace. But  the pace of crop production growth appears to be slowing in some really  important regions, particularly in parts of India and China and, yes,  the U.S.

How did this happen?  Study co-author Jonathan Foley, talking to Science Daily, suggests one  possible explanation. "This finding is particularly troubling because it  suggests that we have preferentially focused our crop improvement  efforts on feeding animals and cars, as we have largely ignored  investments in wheat and rice, crops that feed people and are the basis  of food security in much of the world," he said. Yikes.

What do the data show us?  The authors kindly shared some charts and maps illustrating their data.  As Ray told Science Daily, it "both sounds the alert for where we must  shift our course if we are to feed a growing population in the decades  to come, and points to positive examples to emulate."

Here, first, is what the  data look like for changes in wheat production. The green indicates  rising production (and, again, keep in mind that some growth is  necessary to keep pace with population increases), orange for stagnating  production, and red for a decrease. You'll notice lots of orange (as  well as some green splotches) in Asia.

Here are similar maps for  rice and soybeans. The map for maize (corn) appears at the top of the  page. Again, look closely at quick-growing Asia, where you'll see both  good and bad news, although ideally they would be all green:

And here are some sample  findings from the study's data, showing what it looks when a crop  stagnates growth, collapses, never improved, or is still growing. Take a  look at the sample locations places like Argentina and Morocco are in  there, but so are Arkansas, Texas, and Minnesota and you'll remember  that sustainable crop production really is a global problem.

America's population  might not be growing as quickly as India's or China's, but it is  growing, and its consumption habits tend to require more crops per  person. That's because we need crops not just to feed ourselves but to  fuel our cars and to support our enormous demand for meat and dairy,  which require substantial crop outputs. As Asian societies become not  just larger but increasingly wealthy, the stress on the world's food  supply is expected to increase. If crops are to keep pace, we'll need  more of the world following the examples of places like Big Stone  County, Minnesota, which has seen consistent growth in wheat production.

People have been  predicting a Malthusian crisis, in which population growth outstrips the  world's ability to feed and house everyone, for centuries. The  predictions have all been wrong. Let's hope it stays that way.

Source Washington Post