Soil: The incredible story of what keeps the earth, and us, healthy

by Matthew Evans

Nauru was once a tropical paradise. Before that, it was a toilet. For an estimated 4 million years, prior to human habitation, Nauru was where a lot of seagulls emptied their guts.4 Over millennia, the birds’ poo accumulated, then calcified. After being inhabited by Polynesians and Melanesians for an estimated 3000 years, a European prospector, Albert Fuller Ellis, arrived in 1900. Ellis found what looked like calcified wood on the island, but turned out to be ancient seagull poo – and the richest source of phosphorus ever discovered. A persuasive alliance of three Commonwealth nations, Australia, New Zealand and Britain, stripped 43 million tonnes of phosphate-rich earth from Nauru5 and shipped it off to be used in garden centres, orchards and fertiliser factories the world over. Then, of course, the companies moved on. Today, Nauru’s inland is a wasteland of stalagmite-like peaks, washed of nutrients by tropical rains. To this day the land remains poisoned with the heavy metal cadmium, after subsoils and cadmium-rich rocks were exposed to the air.