Global Manure Map

But the global supply of easily mineable phosphorus is dwindling; to stave off the coming drought, scientists are exploring an alternative: recycling animal manure for its phosphorus content. To make their map (above), researchers used data on livestock density and calculated the annual amount of phosphorus excreted by cattle, pigs, chickens, sheep, and goats globally—as much as a whopping 130,000 kilograms per square kilometer, they report in an upcoming issue of . The researchers hope their map will encourage countries, including India, Brazil, China, and the United States (which together use 66% of the world’s phosphorus fertilizer), to support phosphorus recycling.

Source: www.sciencemag.org