Nitrogen Designs

No, it’s not one of Freud’s theories of obsession, but a natural process by which nitrogen is converted into something else.

Technically, nitrogen fixation covers a range of conversions, but the most common and well-known conversion is nitrogen into ammonia. Why? Because it is absolutely fundamental to Life As We Know It.

The nitrogen released via nitrogen fixation is essential for proteins, and therefore amino acids, which are essential for life itself. There are many things that we could live without (unlike teenage girls & their (http://prom-dresses.net/)prom dresses), but fixed nitrogen is definitely NOT one of them.

Here come the technical bits: Atmospheric nitrogen is called N2 because two nitrogen molecules are bound together. I mean, really bound together (three times, to be exact). It takes an enormous amount of energy to separate them (unlike many compounds made with nitrogen, which are notably unstable!).

Some single-celled organisms (called diazotrophs) synthesize an enzyme called nitrogenase that allows them to fix nitrogen.

A symbiotic bacteria known as Rhizobia likes to hang out in the roots of certain plants (specifically, legumes), happily making nitrogen compounds for its host. When the plant dies, all of that delicious nitrogen fertilizes the soil — the main reason why crop rotation so often includes “green manure” like clover and alfalfa.

Another fun little guy is called Frankia; this bacteria forms a symbiosis with a very select group of plant species. How select? There’s only 22 total, and they represent a wide range of plant families. Trees like Birch and Alder get their nitrogen fix from Frankia, and so do about a dozen shrubs and evergreens, but so does the Datisca, an herbaceous plant that resembles hemp.

On a larger or smaller scale, depending on how you look at it, there’s also the cyanobacteria’s approach to nitrogen fixation. They say that blue-green algae is one of the single most important species in the history of Earth, and it’s the only one that can perform nitrogen fixing in aerobic conditions (i.e., with oxygen around). It does this so well, in fact, that cyanobacteria in coral reefs is about twice as efficient as on land.