Sep 02

“Beyond Carbon: Scientists Worry About Nitrogen’s Effect” (Richard Morgan, NYTimes)

Australia's 470 men's crew negotiates its way through the algae during training on June 24. (Source: ABC News / AAP: Australian Sailing Team)

Remember those huge algae blooms in China that mucked up the water for the Olympic sailing events? The culprit was nitrogen.

An article in the Sept. 2 New York Times looks at concerns about nitrogen, and it’s a good reminder that climate change is complicated — yes, reducing carbon is critical, but that many other things need to be in balance for our world to be healthy.

Here are a few paragraphs that set up the issue:

Public discussion of complicated climate change is largely reduced to carbon: carbon emissions, carbon footprints, carbon trading. But other chemicals have large roles in the planet’s health, and the one Dr. Giblin is looking for in Arctic mud, one that a growing number of other researchers are also concentrating on, is nitrogen.

In addition to having a role in climate change, nitrogen has a huge, probably more important biological impact through its presence in fertilizer. Peter Vitousek, a Stanford ecologist whose 1994 essay put nitrogen on the environmental map, co-authored a study this summer in the journal Nature that put greater attention on the nitrogen cycle and warned against ignoring it in favor of carbon benefits.

For example, Dr. Vitousek said in an interview, “There’s a great danger in doing something like, oh, overfertilizing a cornfield to boost biofuel consumption, where the carbon benefits are far outweighed by the nitrogen damage.”

And here are some troubling numbers that show how agribusiness contributes to nitrogen imbalances:

Fertilizer use is largely inefficient. With beef, only about 6 percent of nitrogen used in raising cows ends up in their meat; the rest leeches out into air or water supplies. With pork, it is 12 percent; chicken, 25 percent. Milk, eggs and grain have the highest efficiency, about 35 percent, or half of what, in the metric of report cards, is a C-minus.

Finally, a good analogy:

Reactive nitrogen competes with greenhouse gases that have greater public awareness. “But it’s like looking at malaria and AIDS in Africa,” Dr. Rabalais said. “They’re both problems. And they both need vigilant attention.”

Read the full article here: Beyond Carbon — Scientists Worry About Nitrogen’s Effect