Robert Law (Photo: Laura Lynch)

Law says he uses it for almost all his crops, because his land is inherently very low in naturally-available nitrogen, which plants need to thrive.

Law is hardly alone. The invention of nitrogen based fertilizer in 1909 helped fuel a global agricultural boom, and it’s been crucial in feeding a growing population ever since.

But a growing number of scientists say that boon to our food supply has come at a big cost—massive nitrogen-based pollution.

Mark Sutton, of the Center for Ecology and Hydrology in the United Kingdom, sums up the dilemma: “We’ve known for many years that using nitrogen for fertilizer is a great thing for farming to increase productivity,” Sutton says. “But there’s a whole range of threats resulting from this nitrogen leaking into the environment.”

Nitrogen itself is an inert gas that’s necessary for life. But Sutton says we’re changing it into forms that are harmful, overloading the environment with it, and throwing the natural nitrogen cycle out of whack.

Nitrogen compounds running off farmland have led to water pollution problems around the world, while nitrogen emissions from industry, agriculture and vehicles make a big contribution to air pollution.

“Massive cost” from Nitrogen Pollution in the EU

Sutton says the cost of all of these impacts is immense. Last year he was part of a team of 200 scientists from 21 countries who studied the problem in the European Union. They calculated the dollar value of the damage of nitrogen pollution at between 90 and 400 billion dollars a year.

That’s “a massive number,” Sutton says.

The cost comes to both the environment and human health. For instance, Sutton says, particulate air pollution caused in part by nitrogen shortens the lives of many Europeans by more than a year.

Overall, the EU report estimated that the cost of nitrogen pollution in the EU is more than double the value that nitrogen fertilizers add to European farm income.

“So these are significant issues,” Sutton says.

The EU study is the first to calculate these costs in Europe. But Alan Townsend, an ecologist at the University of Colorado, says nitrogen pollution is “unquestionably” a global problem.

Townsend says the US is also a major hotspot, and that big problems are emerging in China, Southeast Asia and Latin America.

The impacts of nitrogen pollution can be hard to recognize. Big environmental disasters like oil spills tend to grab all the attention, Townsend says, but “there is essentially a nitrogen spill everyday.”

The irony is that in the right places and chemical forms, nitrogen is valuable stuff. Every ounce of fertilizer that runs off a field into a river is a waste of resources and money.

“Solutions are Right in Front of Us”

But Townsend says it’s a problem that shouldn’t be that hard to solve.

“This is not one of those problems where we sit around scratching our heads and say, ‘Man this is going to be a disaster, how are we going to deal with it, there’s nothing we can do,’” he says. “A lot of the solutions are right in front of us. It’s just about moving down that path.”

That path includes increasing the use of technology to cut nitrogen pollutants from power plants and vehicles, which is already widely used in the US and Europe.

Cutting nitrogen pollution from food production is a more complicated challenge, but Townsend says on the farm field itself, it comes down to a simple principle: use fertilizer more efficiently.

“We have to approach it as an efficiency problem,” he says. “How do we maximize the benefits that we’re going to get from this stuff and minimize the unwanted consequences?”

Farmworker Mark Moule (Photo: Laura Lynch)

His tractor now sports a small computer console with which his farmhands can ensure that each field gets only the exact amount of fertilizer it needs, depending on the crop, the season and the weather.

“We just program each individual field as we come to it,” says Law’s farmworker Mark Moule. ”Just press start and finish and one minute you’ll be putting 50 kilos on per hectare next minutes it’s a hundred and fifty.”

That kind of precision helps reduce the amount of nitrogen that runs off farm fields into nearby streams. It can also help save money on fertilizer.

Economic & Demographic Challenges

But this kind of technology is expensive, and many smaller farms can’t afford it.

For his part, Law is willing to look for even more efficient ways to use fertilizer. But he warns that Britain and the rest of the world face a growing challenge when it comes to feeding a growing population.

“The area available for farming in this country is getting smaller each year,” Law laments. “Roads are being built, towns are being built.”

It’s a global trend—less farmland and more mouths to feed. And that will only add to the challenge of getting rid of the excess nitrogen we’ve been putting into the environment.

I think the word “eclectic” would be a good way to describe this week’s podcast. Of course, “freaking cool” would also be another way to describe our stories this week. Rebecca Bray and Britta Riley, right, are a case in point. WTP’s own Cyrus Farivar ran into Britt and Rebecca at this year’s Ars Electronica 2009 festival in Linz, Austria. The theme for the festival this year is “Human Nature,” and it doesn’t get much more human or natural than, well, waste. Britt and Rebecca, you see, were in Linz to show people how to turn their urine into fertilizer. They’ve got a DIY system to do just that, and they’ll walk Cyrus, and you, through it on this week’s podcast. Oh, and if you think the urine to fertilizer story fits the Human Nature bill, wait until you hear the other story Cyrus unearths in Linz. It’s called The Earth Angel, and it’s proof that the need to go green has pushed into new territory. In this case, the erm, “adult sex toy” industry. Oh, let’s not be prudish. The Earth Angel is a wind-up vibrator. Cyrus and fellow tech reporter Sonja Bettel, an Austrian herself, give it (a very platonic) test run on the podcast.

A couple of podcasts ago, I told you about a cool project by some cyclists in San Francisco. They’re using GPS and other technologies to map out routes around San Francisco. Not just any routes, though. When they ride the route, the software draws that route on a map. The drawing, if done right, turns out to be, in this case, some well known Atari characters. In my excitement, I may have made it seem like this is something new. Not so, and long-time listener Brett Stalbaum let me know it. Brett teaches computers in the visual arts at UC-San Diego. So, I invited him on the podcast to give us the low-down on the great mash-ups between GPS and art. Brett’s done some really cool stuff himself, as you can see. Thanks to Brett for agreeing to be on the podcast, and for setting me straight.

And we end with the beginning of the podcast, actually. Reporter Akiko Fujita tells us about a student project at the University of Nagasaki. Students and their professors are collecting the memories of those who survived the U.S. atomic bomb strike in August of 1945. The idea is to recreate, in 3D, what the Urakami neighborhood of Nagasaki looked like before the war. Here’s the video I promised:

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