Smil started out by telling us how although nitrogen in a *stable* form (paired nitrogen atoms) makes up 78 % of the atmosphere, a very tiny amount of a *reactive* form of nitrogen that plants can absorb exists naturally. The splitting of the paired nitrogen into compound ammonia is performed naturally by such things as the force of lightning, or by the actions of nitrogen-fixing bacteria and cyanobacteria. This process is called nitrogen "fixation".

Since ancient times traditional farmers would raise beans and other plants (such as peas, lentils, or acacia trees) next to their cereals and other crops because they knew the nitrogen-fixing bacteria lived and created nodules on the roots of these beans and peas and would help supply the soil with nitrogen that their crops would need. These "green manure," along with the adding of human and animal wastes to the fields, provided a limited amount of nitrogen per hectare of arable land, and this limited supply of nitrogen could only support a limited amount of population on earth. Population growth up to this time (around 1900) was limited worldwide -- it was a natural limit of existing usable (reactive) nitrogen mankind could garner through natural farming techniques.

By 1890s the knowledge of a nitrogen crisis was recognized and attempts began to be made by scientists to "break the nitrogen barrier". First, in 1899 Carl Bosch, a German, came up with a breakthrough process of ammonia synthesis. Then Frisz Haber, a German jew, devised a workable technique to synthesize ammonia from nitrogen and hydrogen. Then it was Bosch again who solved Haber's design problem. The Haber-Bosch technique helped Germany during the first World War (nitrogen compounds were used in making explosives) but the agriculutral use languished through the two world wars where the global ammonia production was below 5 million tons per year.

By 1950s, nitrogen fertilizer use rose to 10 million tons per year. By the 1960s rich nations accounted for over 90% of worldwide nitrogen fertilizer use. But by 1980s their share dropped and by now developing nations accounted for more than 60% of the global nitrogen fertilizer output. This use of nitrogen fertilizer was the reason why global population rose so sharply since 1900s. Currently approximately 175 million tons of nitrogen fertilizer are dumped into the world's soil each year. The various crops we consume take about 40% of its nitrogen from nitrogen fertilizer. Because these fertitlizers provide about 75% of all nitrogen in consumed proteins, so about 1/3 of humanity's protein derived from nitrogen fertilizer.

A whole range of ill effects nitrogen wreak makes global warming pale in comparison. In addition to nitrogen fertilizer used in farms, human's burning of fossil fuels also releases nitrogen, and clearing of forests and wetlands also "liberates introgen that would otherwise be stored". The amount of atmospheric nitrogen has doubled over the past century!!!

The ill effects of the man-made increase of nitrogen range from "blue baby" disease (methemoglobinemia) in infants, to ground and surface water contamination. The latter is called "eutrophication," or the enrichment of water by nitrogen, which leads to algae overgrowth. The oversupply of nitrogen also probably caused the decreases in the number of species and the decline in fish catches in many areas.

The nitrogen that stays in the ground is also harmful. It causes the over-acidification of the soil, which can lead to loss of other soil nutrients and release of heavy metals into the water supply.

The atmosphere is also noxiously affected. More nitrous oxide is released into the atmosphere. Reaction of this gas with oxygen contributes to the destruction of ozone and promotes the greenhouse warming. Not to mention nitrous oxide has an atmospheric lifetime of more than a century.

Smil pointed out that the emission of carbon dioxide from our use of fossil fuels can potentially be reduced but THERE'S NO ALTERNATIVE FOR NITROGEN FERTILIZER! There's no substitute for the Haber-Bosch synthesis: our crops, our bodies depend on it. To Smill, perhaps one day a bacteria, or a cereal with the ability to fix nitrogen, can be genetically-engineered, but none is imminent. So humanity is left with billions of mouth to feed (global population is estimated to reach 10 billion during the next century !@#$...) and it can only be done with nitrogen fertilizer!!!!

What do we do? What do we do? We can all become vegetarian and thus eliminate the wasteful process of feeding nitrogen-filled feeds to livestocks. But the opposite is the trend: meat consumption is on the rise worldwide. Global reduction of nitrogen fertilizer is the answer. Effective governmental control of the amount used by farmers must be implemented. Ideally, organic farming is the answer. But as Smil puts it, "If all farmers attempted to return to purely organic farming, they would quickly find that traditional practices could not feed today's population. There is simply not enough recycable nitrogen to produce food for six billion people."

The last paragraph of the article Smil sums it all up as:
"Barring some surprising advances in bioengineering, virtually all the protein needed for the growth of another two billion people to be born during the next two generations will come from the same source - the Haber-Bosch synthesis of ammonia. In just one lifetime, humanity has indeed developed a profound chemical dependence."

Is it our destiny on earth to ignite the next mass extinction? So much for those special "intellectual," "linguistic," and "moral" faculties we boast of having over and above the rest of the species. Seems to me the only things we have above them are hubris, arrogance, and unearned pride -- a disease of an over-identification with our own "thoughts". But have we given any thoughts on what we've done to our fellow earthlings and to the earth itself?

But then again, if another organism already caused one mass extinction (the oxygen holocaust), why can't we humans be the next agent of mass extinction -- we're an organism!?!?!?! And mass extinction is probably just a natural thing. There's been five mass extinctions so far already. A sixth one must be in order. And why not by mankind?!?!?!?

Or this worry is for naught and extra nitrogen would just be extra nitrogen, no harm done... Who knows....

WORK CITED
"When Nutrients Turn Noxious." Environment section, page 24. Scientific American Magazine, June 1997.
Smil, Vaclav. "Global Population and the Nitrogen Cycle." Scientific American Magazine, July 1997.