By the 1800s, intensive agriculture had seriously depleted soil fertility along the East Coast of the United States. Guano mined from Pacific islands offshore from Peru became a prized imported fertilizer. Competition for that resource led to an 1856 law directing the country to secure access to guano by claiming sovereignty over unclaimed territories.
Bright blue ponds looming out of the red desert landscape near Moab, Utah, recently prompted my interest in the potash harvested from the pools. The potassium-bearing contents of the ponds will become a key ingredient of synthetic fertilizers. These are essential to feed the growing population on our planet, but fertilizer components are not in infinite supply, plus are causing many environmental problems.
In the past century, manufacturing nitrogen fertilizers with ammonia has been explosive (even literally...). Increases in crop production from manufactured fertilizers have benefited tens of millions of people. Unfortunately, this fertilizer produces tremendous waste in an inefficient process that is highly polluting; we could lower global use with alternative methods. Over 500 years ago, the Incas implemented laws to conserve their valuable guano fertilizer.
