Land Sparing, Water Saving, and the 2012 U.S. Drought

, scientific adviser, Climate and Energy | August 9, 2012, 1:57 pm EST
Bookmark and Share

The drought of 2012 has reminded us that water is a scarce resource, even though we pay fractions of a penny per gallon for it and expect that it’ll be there every time we turn on the tap. We depend on it not only for our drinking and washing and especially for the food we eat, but also for generating the electric power on which our economy depends.

Drought in AmericaThis is part of a series on the 2012 Drought in America.


There’s no doubt that we can use water more efficiently and that this would be socially and ecologically desirable. But this week, as I’ve being participating in the Annual Meeting of the Ecological Society of America (ESA) in Portland, I’ve started to doubt whether efficiency will really solve our drought and water problems. The reason is that for another vital resource — the land — efficiency doesn’t seem to be enough.

The hypothesis that using land to produce food more efficiently — that is, increasing agricultural yields — will “save” more land for nature, is called “land sparing” and is often associated with the famous crop breeder Norman Borlaug. It was the subject of a session of scientific presentations here at the ESA yesterday, including one by me. Although I’m by no means unbiased on this subject, I’d say that the messages of the presenters about the validity of the land sparing hypothesis mostly ranged from “It’s wrong” to “it depends.”  (I gave both answers, but with more emphasis on the first one.)

A complex landscape being simplified: a palm oil plantation replacing tropical rainforest in Borneo. SOURCE: Rhett Butler,

An example of the first was the talk by Jahi Chappell of the University of Washington-Vancouver, who showed that increasing agricultural yield seems to do much less to reduce hunger in developing countries than social changes such as improving the status of women. The second kind of answer came in the presentation of Frank Egan of Penn State, who argued that land sparing works to preserve plant biodiversity in simple environments, but that in more complex landscapes a different strategy, “land sharing,” is preferable.

Laurie Drinkwater of Cornell University made the connection between agriculture and water quality, showing how U.S. agricultural and biofuels policies that promote massive corn production in the Midwest lead to excessive applications of nitrogen fertilizer, much of which runs off and contaminates streams, rivers, and ground water.

Land that hasn’t been spared: the tallgrass prairie in Illinois. SOURCE: K.R. Robertson, Illinois Natural History Survey.

If there’s any place that land sparing ought to work, it’s in the Corn Belt, where high-input farms produce record crop yields (except in drought years like this one, likely to be increasingly common in the future). Yet the result, contrary to the land sparing hypothesis, has been a landscape with practically none of its original nature (the tallgrass prairie) remaining, and water pollution that creates an enormous “dead zone” in the Gulf of Mexico, a thousand miles away.

If high productivity doesn’t spare land, how about water? As I said in my presentation, the error of the land sparing hypothesis was first pointed out 150 years ago by the British economist William Jevons. That error is to ignore the economics, which often leads to more use of a resource whose yield increases, not less.  Jevons was talking about coal, but the same point applies to land. And if it’s true for water as well, then more efficiency won’t save us from this drought – or the next.

Posted in: Food and Agriculture, Global Warming Tags: , , ,

Support from UCS members make work like this possible. Will you join us? Help UCS advance independent science for a healthy environment and a safer world.

Show Comments

Comment Policy

UCS welcomes comments that foster civil conversation and debate. To help maintain a healthy, respectful discussion, please focus comments on the issues, topics, and facts at hand, and refrain from personal attacks. Posts that are commercial, self-promotional, obscene, rude, or disruptive will be removed.

Please note that comments are open for two weeks following each blog post. UCS respects your privacy and will not display, lend, or sell your email address for any reason.

  • Craig

    The situation in the Corn Belt is complex. From what I see, it’s true that Jevons’ paradox holds, as we’ve seen major wetland drainage for cropping since the end of World War II. At the same time, as intensification of agriculture increased, some marginal lands were abandoned for agriculture. The largest blocks of forest in southern Wisconsin (currently protected by the public agencies and The Nature Conservancy) include areas that were cleared for cropping and pasture but were abandoned beginning with the Depression and as farm sized and mechanization increased. Of course, due to to major reorganization of ecosystems that occurred during European settlement, biodiversity and ecosystem function may not recover as an alternate stable state composed primarily of non-native species becomes established. Such is the fate of much of the marginal land that has been abandoned from agriculture in Wisconsin.

    • Craig,

      Thanks for pointing out the complexity of the land-use situation in the Corn Belt due to historical factors. Somewhat further west, in the wheat belt (the Dakotas, Nebraska, etc.) there was a somewhat similar process a hundred years ago, with expansion into the drier parts of the prairies around the turn of the twentieth century during the initial wave of European settlement. (My great-grandfather, who moved from Illinois to Eureka, South Dakota, was part of this wave.) Although the dryness of the region was recognized, the theory that “rain follows the plow” reassured farmers that once the land was settled, precipitation levels would increase.

      For a while this seemed to work, with good harvests for several years in the late 1800s. But soon droughts became more frequent, crops failed, and much of the marginal land had to be abandoned. Many small towns in the region have never recovered.


  • Albert

    Inefficient use of resources is the answer,then?

    To get the ball rolling will we need to subsidize wastefulness or will the inherent value of inefficiency float to the surface to animate and enrich the professionally incompetent? When we truly master the art of inefficiency will so much land and water be spared that some will actually be created by spontaneous generation? Could inefficiency explain the birth and evolution of the universe?

    Oh, I smell a Noble prize just over the horizon!

    • It’s a simple error of logic to think that if one proposed solution to a problem doesn’t work, then the opposite solution will. Alas, reality is more complicated!