Hi, this is Alex, from MinuteEarth. Russia
is the biggest country in the world, China is the most populated, and the US is the richest.
And then there’s Morocco… which isn’t exactly a global superpower. But it is one
of the most important places in the world, because of phosphorus. The element phosphorus is critical for civilization
– plants need it to grow, and we need plants to eat. Soil naturally contains some phosphorus
that’s available to plants, but every year, some of it leaves our fields through erosion
and some of it leaves when we harvest the plants that absorbed it. So we need to add
more phosphorus. We add some in the form of poop from plant-munching farm animals, but
there’s not enough animal poop to replenish all the phosphorus we need to keep growing
food for our growing population. Luckily, some rocks are really rich in phosphorus.
And Morocco is home to most of them – at least the ones we can reach. The vast majority are
actually sitting at the bottom of the ocean. That’s because these so-called phosphate
rocks formed over millions of years as ocean-dwelling microorganisms died and their phosphorus-rich
bodies sank to the seafloor. This happened throughout the ocean, but the phosphorus only
concentrated on the seafloor in a few special places. In these places, there were tons of
microorganisms, there were no rivers (which would have diluted the phosphorus with other
sediments), and there were occasional ocean currents that carried away any lighter non-phosphorus
sediments. This rare combination of conditions allowed the phosphorus-rich sediment to concentrate
into phosphate rocks, and it just so happened to occur throughout the ancient ocean that
covered what is now Morocco. As a result, modern Morocco has almost ¾
of the world’s accessible reserves of phosphate rock. That’s an unheard of concentration
of a single major resource in one country. I mean, China has more rare earth metals than
any other country, but that’s only around a third of the world’s reserves. And Saudi
Arabia and Venezuela have more oil than anyone else, but they each have less than 20% of
the world’s reserves. Morocco has so much of the world’s accessible
phosphate rock that without its reserves, humanity doesn’t even have enough to last
100 years. But even if Morocco shares nicely with everyone else, humanity will only have
around 300 years. Sure, 300 years is a long time from now, but
we’ve been relying on farming to feed towns, cities, and civilizations for 10,000 years.
Even if we discover another huge supply of phosphate rock or figure out how to mine it
from the seafloor, that too will eventually run out. At that point, we could wait until
the phosphorus running off our fields flows into the ocean, reaches one of those special
places, concentrates again into phosphate rock, and ends up above water. But that would
take a few million years, and we’d go hungry long before then. So if we plan to be a food-eating
civilization into the distant future, we need to use and recycle phosphorus more effectively.
In other words, we’ve got a problem to solve — a problem with a capital P.
This video was sponsored by the University of Minnesota, where students, faculty and
staff across all fields of study are working to solve the Grand Challenges facing society.
One of these challenges is feeding the world sustainably, and part of the solution is to
ensure we have enough phosphorus to grow crops. In the Department of Soil, Water, and Climate,
professor Carl Rosen and graduate student Persephone Ma are researching whether it’s
possible to get useful amounts of phosphorus from unexpected places – like burnt sewage
– as a way to reclaim phosphorus from our own waste and put it back on our fields. Thanks,
University of Minnesota!