Tuesday, March 25, 2014

100 Years of Norman Borlaug

Marginal Revolution reminds us that Norman Borlaug was born 100 years ago today.

If you read the comments on that site, you'll see a good deal of triumphalism. MR is a libertarian-leaning blog, and I would guess the readers rely heavily on the ideology that human cleverness and innovation will solve any problem. There's even a tagline at the bottom, "The man who proved Malthus wrong born 100 years ago today" But did he?

I won't unpack that question in any depth here, except to point out that this sort of triumphalism seems mainly to come from economists and businesspeople rather than people who actually grow food (the lords are more certain about higher crop yields than the peasants). For a more critical view, see this article by Nafeez Ahmed: Dramatic decline in industrial agriculture could herald 'peak food' (The Guardian)
Past trends over the last five decades of perpetually increasing crop yields were "driven by rapid adoption of green revolution technologies that were largely one-time innovations" which cannot be repeated. These include major industrial innovations such as "the development of semi-dwarf wheat and rice varieties, first widespread use of commercial fertilizers and pesticides, and large investments to expand irrigation infrastructure."

Although agricultural investment in China increased threefold from 1981 to 2000, rates of increase for wheat yields have remained constant, decreased by 64% for maize and are negligible in rice. Similarly, the rate of maize yield has remained largely flat despite a 58% investment increased over the same period. The study warns:

    "A concern is that despite the increase in investment in agricultural R&D and education during this period, the relative rate of yield gain for the major food crops has decreased over time together with evidence of upper yield plateaus in some of the most productive domains."

The study criticises most other yield projection models which predict compound or exponential production increases over coming years and decades, even though these "do not occur in the real world." It notes that "such growth rates are not feasible over the long term because average farm yields eventually approach a yield potential ceiling determined by biophysical limits on crop growth rates and yield.
And from the Agroinnovations podcast: What is the Agrocollapse?

I'm reminded of something I posted a few years back: A Limit to Gains From Genetically Engineered Cotton (New York Times)
After collecting four rounds of data from more than 500 farms in total, Dr. Qaim and a graduate student, Jonas Kathage, looked at the farmers’ cotton yields profits as well as their household expenditures, a marker of the farmers’ standard of living.

They found that using the modified seeds increased the farmers’ cotton yields by 24 percent and their profits by 50 percent. Farmers’ harvests improved mainly because the genetically altered plants suffered less damage from insects, Dr. Qaim said; profits grew as a result of the larger yields.

But as genetically modified seeds take over cotton production in India — in 2010, so-called Bt cotton plants covered about 90 percent of the land used to grow the crop in India, according to a report by the Central Institute for Cotton Research — farmers may cease to reap added benefits from their use, Dr. Qaim said. Because the modified seeds are used so widely, bollworms may develop a resistance to the toxins, he explained.

Although farmers are planting more and more acres with cotton, their productivity seems to have plateaued; cotton yields have not increased since the 2007-8 growing season.

“A technology can lift yields, but once you have lifted yields, what else can that technology do?” Dr. Qaim said.
Anyway, make up your own mind. I'll just leave you with this:
A parasitic worm is becoming rapidly resistant to the corn that was genetically engineered to kill it, according to a new study.

Published Monday in the Proceedings of the National Academy of Sciences, it’s a cautionary tale of how bioengineering is only beneficial until evolution manages to catch up — and how mismanagement of biotech crops can hurry up that process.

The crop in question, known as Bt corn, was first planted in 1996. Able to resist rootworms and corn borers, it helped farmers increase their yields and reduce their use of conventional pesticides. It worked so well that it now accounts for three-quarters of the U.S. corn crop.

“Unless management practices change, it’s only going to get worse,” Aaron Gassmann, an Iowa State University entomologist and co-author of the study, told Wired. “There needs to be a fundamental change in how the technology is used.”
Evolution one-ups genetic modification (Salon) Happy birthday Dr. B!

1 comment:

  1. Thanks for the link. I think Borlaug's contribution was tremendous, but it has been a double-edged sword. Dimishing returns is like a corollary law of physics; it is one of the greatest achievements of economics to our understanding of the world. Pity few people realize or pay attention. Certainly the green revolution is at the point of diminishing returns. Interesting that we haven't even tried to discover that with sustainable agriculture.

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