The layers of rock exposed in the trench date back more than a hundred million years, when England was submerged in warm, shallow seas. Kelly, a researcher at a non-profit geology consulting firm, specializes in marine fossils of that era (“Dicranodonta vagans !”He exclaims when I locate a stone riddled with prints of tiny clam-shaped shells, which he asks to preserve. That’s why he had the ditch dug with an excavator in 2015, and that’s why he’s spent countless hours since looking at his treasure. “You’re going to Simon’s hole, aren’t you?” Kelly’s wife had no emotion when I picked him up the morning of my visit.
He had come because Simon’s Hole also contained elements of more recent old importance: circular and opaque pebbles that once helped feed the UK. By the 19th century, centuries of cultivation had undermined British soils with nutrients, adding phosphorus, a detail for crops At that time, manure and bones were not unusual phosphorus resources, and when the country depleted its internal reserves, it looked elsewhere.
“Britain is like a continent ghoul,” wrote Justus von Liebig, the German chemist who first learned about the fundamental role of phosphorus in agriculture. “Already hungry for bones, she discovered the battlefields of Leipzig, Waterloo and Crimea; already from the catacombs of Sicily, it has taken the skeletons of many successive generations.
Then, in the 1840s, geologists discovered phosphorus-rich stones buried in the fields around Cambridge, the same elegant brown rocks welded into the walls of Kelly’s pit. “That’s what they were for,” he says, pointing to a layer of grouping the length of a bean into a chestnut tree.
First, these nodules were thought to be fossilized faeces and are known as copolites, meaning “manure stones”. It was discovered that most were fragments of mineralized sediment, but this did not diminish its usefulness as fertilizer.
“In the remains of an extinct animal world, England will have to find tactics to increase its wealth in agricultural products,” Liebig wrote. “May its just population redeem the most of poverty and misery!”And that was.
In the following decades, 2 million tons of coprolitos were extracted, turning the fields and marshes of south-east England into a maze of wells and trenches that eclipsed Simon’s hole. The coprolitos were classified, washed and transported through buggy, exercise and barge. channel to processing facilities, where they were crushed and treated with acid to produce superphosphate, the world’s first chemical fertilizer.
The rocks helped Britain build its food source and consume the so-called agricultural revolution of the time (the first “revolution” was the emergence of agricultural civilization). Coprolites and other geological deposits of phosphorus have also raised the attractive choice that humans have yet was freed from a centuries-old biological restriction. For billions of years, life on Earth had struggled with a lack of phosphorus. Finally, that was about to change.
Life as we know it is based on carbon, but the body also wants other details, such as the addition of nitrogen and phosphorus. Nitrogen is the basis of all proteins, from enzymes to the muscles and nucleic acids that encode our genes. Phosphorus bureaucracy, DNA scaffolding, moving membranes and our skeletons; is a key detail of tooth and bone minerals.
Too little of these nutrients will restrict the productivity of organisms and, through extension, entire ecosystems. On short timescales, nitrogen is depleted first. But this rarity never lasts long, geologically speaking: the environment, comprising about 80% nitrogen. – represents an almost infinite deposit. And at the beginning of evolution, some microbes have developed tactics to convert atmospheric nitrogen into biologically available compounds.
Unfortunately, there is no similar trick to phosphorus, which basically comes from the Earth’s crust, organisms have sometimes had to wait for geological forces to crush, dissolve or otherwise abuse the planet’s surface to ooze phosphorus, this alteration procedure can take thousands or even millions of years. And once phosphorus nevertheless enters the ocean or soil, where organisms can simply use it, much reacts in inaccessible chemical forms.
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For these reasons, editor and chemist Isaac Asimov, in a 1959 essay, called phosphorus a “bottleneck in life. “Noah Planavsky, geochemist at Yale University, says scientists have come to the same conclusion: “This is what limits the capacity of the biosphere. “
One of the persistent mysteries about the origin of life, in fact, is how the first organisms received enough phosphorus to unite their primitive cellular machinery. Some scientists may have evolved in environments with abnormally high concentrations of phosphorus, such as closed phosphorus. Others have warned that bioavailable phosphorus came to Earth in the form of comets or meteorites, a heavenly gift that helped revive life.
Chronic phosphorus scarcity may also be the reason why oxygen has taken so long to build up in the Earth’s atmosphere. Phytoplankton began to fuel about 2. 5 billion years ago, with the advent of photosynthesis, but they may not have had enough phosphorus to boost production, according to studies through Planavsky and others, because the detail continued to be connected to iron ores in the ocean, helping to trap the global in a low state of oxygen for more than a billion years later.
That we are breathing oxygen today, and that we exist at all, may be due only to a series of climate cataclysmos that have temporarily liberated the planet from phosphorus limitation. About 700 million years ago, the oceans froze several times and the glaciers swallowed up. continents, chewing the rock beneath them. When the ice nevertheless melted, giant amounts of glacial sediments poured into the seas, offering unprecedented amounts of phosphorus to the undeniable bureaucracy of marine life that then populated the planet.
Planavsky and his colleagues recommend that this influx of nutrients has opened a door to evolution. Over the next hundred million years, the first multicellular animals gave the impression and oxygen concentrations eventually began to rise to fashion levels. Scientists are still debating what happened. however, phosphorus probably played a role (for Planavsky, this is “one of the most desirable unresolved questions about the history of our planet”).
Another organization of scientists, led through Jim Elser of Arizona State University, hypothesized that such a pulse of phosphorus may also have had other evolutionary consequences: since too much phosphorus can be harmful, animals could possibly have started building bones to bind excess nutrients together. “Awesome, isn’t it?” says Elser, so true. “
What is clear is that after this explosion of life, the phosphorus knot tightened, geological aging has continued to distribute mea few rations of nutrients and ecosystems have developed tactics to conserve and recycle it (in lakes, for example, a phosphorus atom can be used). thousands of times before sediments are achieved, Elser says. ) Together, these geological and biological cycles of phosphorus were the rhythm and productivity of life. Until fashionable humans arrived.
However, long before the discovery of phosphorus, humans had invented wise tactics to manage their local supplies, says Dana Cordell, who heads the food systems studies organization at the University of Technology in Sydney, Australia. Indigenous peoples controlled hunting and feeding grounds with fire, fertilizing the landscape well with biological phosphorus in ash, among other benefits. In agricultural societies, farmers have learned to use compost and manure to maintain the fertility of their fields. played a vital role in biblical times; its nutrients, which contain nutrients, helped help the orchards and gardens of desert cities.
But human waste was perhaps the most precious fertilizer of all. Although we also want phosphorus (represents about 1% of our body mass), the maximum phosphorus we consume passes without touching us. According to the diet, approximately two-thirds end. In the urine and the rest in the stool. For millennia, others have collected these valuable ingredients in the early hours of the morning, giving rise to the term nocturnal soil, and used them to grow food.
The wastewater of the Aztec Empire fed its famous floating gardens. Faeces have become so valuable that the government in Edo, Japan, banned baths that flowed into watercourses in the 17th century. In Shanghai, 1908, a visiting American pedologist named Franklin Hiram King reported that the “privilege” of collecting 78,000 tons of human by-products charged the equivalent of $31,000.
King, an ancestor of the biological agriculture movement who worked briefly at the U. S. Department of Agriculture, admired this prudent reuse of waste and lamented that he saw nothing like it at home. This, King writes, was an unfortunate-looking effect of fashion sanitation, which “we are going to be one of the wonderful achievements of our civilization. “
The so-called sanitation revolution closely followed the trade revolution. In the 1700s and 1800s, Europeans and Americans moved to cities in unprecedented quantities, depriving the land of their waste and phosphorus. He forced leaders from countries like London to locate tactics to get rid of the abundant excretions of its inhabitants.
Liebig and other Victorian thinkers argued that these wastewater deserves to be transported to the field and sold to farmers as fertilizer, but the volumes in question raised logistical problems and critics raised considerations about the protection of remedy plants and their smell. The waste was eventually sent to rudimentary treatment centers for disposal or, more often, dumped into rivers, lakes and oceans.
This created what Karl Marx described as the “metabolic division,” a damaging disconnect between humans and the soils they were in, and broke the human phosphorus cycle, reconfiguring their circuit into a one-way pipe.
“This unmarried disturbance caused global chaos, you could say,” Cordell says. On the one hand, this has forced farmers to locate new phosphorus resources to update nutrients lost each year in urban sewers. To make matters worse, agricultural studies in the past 19th century warned that plants needed even more phosphorus than previously thought, and thus began a frantic race for fertilizers.
Spain and the United States claimed uninhabited islands in the Pacific Ocean, where staff collected impressive accumulations of bird droppings (including Midway Atoll, later an American naval station). and remodeled the bones of countless bison sacrificed through fur hunters in the Great Plains.
During these exploits, humans traveled long distances to find safe phosphorus. The discovery of coprolites in British fields has also allowed them to go back in time, capturing nutrients from another era and completely avoiding the geological cycle of phosphorus. the tenacious network in a torrent, and that’s exactly what we did.
Until the last 19th century, the “hedioned stones” doting south Carolina fields were a nuisance, but as the imported guano charge soared and the civil war reformed South agriculture, scientists discovered that these herbal phosphate nodules can become decent fertilizers In 1870, the first American phosphate mines opened near Charleston and along the coast , traversing fields, forests and swamps to succeed in the rocky bed below.
A decade later, geologists discovered even larger deposits in Florida (to date, most phosphorus in US fields and plates) was found. But it’s not the first time It comes from the southeastern United States). , the Middle East and North Africa.
These deposits have become increasingly vital in the twentieth century, the Green Revolution (the third revolution of agriculture, if you keep a trail). Plant breeders have developed more productive crops to feed the world and farmers have fed them nitrogen fertilizers, which now the main obstacle to crop expansion was phosphorus, and as long as phosphate mines were buzzing, that was not a limit at all. 1950 and 2000, global herbal phosphate production increased sixfold and helped the human population more than double.
But while scientists perceive the importance of phosphorus, other people are afraid to run out of it. These fears triggered 19th-century fertilizer races, as well as a series of troubling reports in the 20th century, which added one as early as 1939. , after President Franklin D. Roosevelt asked Congress to compare the country’s phosphate resources so that the materials need to be insured. “
There were also warning stories: large phosphate deposits on the small Pacific island of Nauru supported agricultural advances in Australia and New Zealand during the 20th century. But during the 1990s, Nauru’s mines sold out, leaving its 10,000 inhabitants in destitution and the island in ecological ruins. (In recent years, Nauru has housed a debatable immigrant detention centre for Australia. )
These occasions posed a frightening possibility: what if the phosphorus valves were suddenly closed, relegating humanity once to the ends of its parish phosphorus loops, what if our release from the geological cycle of phosphorus was only temporary?
In recent years, Cordell has expressed fear that we will be consuming our richest and highest reserves available. Phosphate production has fallen by 50% since 1980 and the country, once the world’s largest exporter, has become a net importer. By some estimates, China, now the largest producer, would possibly have only a few decades of supply. According to existing projections, global production of herbal phosphate may also begin to decline well before the end of the century. This poses an existential threat,” Cordell says, “We now have a large population that depends on those phosphorus supplies. “
Many experts dispute those horrible expectations. They argue that the peak of phosphorus, like the peak of oil, is a spectrum that turns back just before its prophecy becomes a reality. Humans will never extract all phosphorus from the Earth’s crust, they say, and whenever we’ve needed more in the world. In the past, mining corporations have discovered this. ” I don’t think anyone really knows how many there are,” says Achim Dobermann, a leading scientist at the International Fertilizer Association, an industrial group. But Dobermann, whose task is to ask for phosphorus, is convinced that “in any case, it will last several hundred years. “
Simply extracting more phosphate from herbs might not solve all of our problems, says Cordell. Already, one in six farmers in the world cannot buy fertilizers and phosphate costs have started to rise. Due to a tragic geological rarity, many tropical soils also trap phosphorus well, forcing farmers to apply more fertilizers than their counterparts in other parts of the world.
The incredibly asymmetrical distribution of phosphate and rock resources adds an additional layer of geopolitical complexity. Morocco and its disputed territory, Western Sahara, involve approximately three-quarters of known global stocks of herbal phosphate, while India, European Union countries and many other countries rely heavily on phosphorus imports. (In 2014, the EU added herbal phosphate to its list of critical raw tissues of greatest threat and economic importance. )
We’ve already figured out how the phosphorus source chain can go wrong. In 2008, at the height of a global food crisis, the load of phosphoric rock rose by almost 800% before falling again in the following months. The reasons were many: a collapse of the global economy, a build-up of India’s phosphorus imports, and a minimisation of China’s exports. But the lesson is clear: in practice, phosphorus is an undeniably limited resource.
Phosphorus is an old parable of herbal resources: humans struggle with a kind of scarcity for centuries, then, despite everything, we find a way to succeed over it. We are extracting more and more than we want, in the call to improve. the human condition, rarely through the transformation of society through remarkable revolutions, but despite everything, and regularly too late, we notice the burden of overexertion. pollution. ” We have too small a problem, too big,” says Genevieve Metson, an environmental specialist at Linking University in Sweden, “which makes this verbal exchange very difficult.
After every step of your journey, from the mine to the box and toilet, the phosphorus leaks into the environment. This leak has more than doubled the speed of the global phosphorus cycle, devastating water quality in the world. A 2017 study estimated that maximum phosphorus grades altered watersheds covering about 40% of the Earth’s surface and home to approximately 90% of its population. More specifically, these contaminants tend to fill water bodies with viscous, smelly foam.
Too much phosphorus, or nitrogen, shakes the aquatic ecosystems that have long been accustomed to modest supplies, Elser says, triggering the proliferation of algae that cause water to turn green, cloudy and fragrant. “they like to see their toes,” Elser observes, but they can also produce toxins that damage and disrupt drinking water supply. And when algae die, decomposition absorbs oxygen from the water, killing fish and creating devastating dead zones.
In fact, pollutants would possibly be the most productive argument for reducing our dependence on extracted phosphorus. “If we take all the phosphorus from the ground and move it into the system, we’re done,” Elser says. Some researchers have estimated that out-of-control human phosphorus inputs, combined with climate change, can also eventually push much of the ocean into a persistent antoxic state for millennia. “I’m pretty sure we don’t need to do that,” Elser says, laughing. Such occasions have occurred many times in Earth’s history and are believed to have caused several mass extinctions, for example, when terrestrial plants evolved and sent a newly altered pulse of phosphorus to the ocean.
The transparent consensus among phosphorus experts is that humans want to start repairing the phosphorus cycle to reduce environmental damage caused by pollutants and waste less of a scarce resource or, like a button I once saw Elser use, save p (ee).
Even the industry has recovered: Yara, one of the world’s largest fertilizer suppliers, recently announced a partnership with European waste giant Veolia to recycle phosphorus from agricultural and food waste. Dobermann says that for many companies, sustainability “is a priority. “
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Human waste recycling is the maximum direct way to close the phosphorus cycle. A Canadian company called Ostara has installed systems to extract phosphorus from wastewater at municipal treatment plants in more than 20 cities around the world, adding Chicago and Atlanta. Switzerland and Germany have even passed legislation requiring the recovery of phosphorus from wastewater that will come into force over the next decade.
The chance of phosphorus recovery from animal manure is even greater. If you get 40 PhDs in a room, we end up talking about cows, Elser says. That’s because there are so many of them. And because the last primary alteration of the phosphorus cycle was in cattle.
Throughout much of human history, farmers have grown crops and animals look-to-look, making it easier for them to recycle manure as fertilizer. However, during the twentieth century, agricultural specialization separated cattle farms and grain producers, over too giant distances to send manure.
This geographic division broke well the last remaining strand of the human phosphorus cycle, and this has led to excess phosphorus in spaces of intense animal agriculture, exacerbating pollutant disorders in places like Chesapeake Bay, Wisconsin Dairy Rivers and Lake Erie. examined through Metson et al. , 55 pounds of phosphorus are released in the vicinity for every pound of phosphorus that is fed in beef raised in the US. U. S. , more than comes from manure (for wheat, the ratio is about 2 to 1. )
In theory, recapturing this match can make a big difference. Metson and others said U. S. cattle waste has been in the middle of the world. But it’s not the first time They contain more than enough phosphorus to help the entire U. S. maize crop. Other research found that recycling all manure can halve global demand for herbal phosphate. We want to replace our minds,” says Graham MacDonald, Metson’s collaborator and agricultural geographer at McGill University. “These are not waste streams,” he says. These are resource flows. “
On a cold December day, Joe Harrison and I finished six feet away, dressed in masks, in a fenced gravel box at Washington State University’s Puyallup Research and Extension Center. Harrison is a nutrient control expert at WSU, and we met at a phosphorus convention in 2018, where he told me about the cell recycling unit that would come to extract phosphorus from manure.
Now the ship is in front of me: an 18-foot-long steel funnel folded into a tray trailer surrounded by green scaffolding, electrical panels and a collection of tubes. In recent years, Harrison and his colleagues have towed the unit to dozens of first, a pump sucks liquid manure into massive plastic tanks, where it is treated with acid, then the powder flows through a thick pipe to the base of the funnel, where it is mixed with other chemicals and begins to form estruvite, a pearly white mineral containing phosphorus (researchers load crystal germs previously to announce the reaction). As manure is treated, the struvite is deposited at the back for collection.
The task is intelligent and pragmatic. Humans are unlikely to start developing all our food on small-scale varied farms where manure can be recycled in the ancient world (it’s work, Dobermann observes). But technologies like this offer an opportunity to close the phosphorus circuit even over long distances. For example, Harrison needs to return the harvested estruvite from the dairy to the farms in East Washington that provide them with food. “Why not capture some of that phosphorus in western Washington and send it back east, where the alfalfa grows?”He says.
Harrison’s unit eliminates up to 62% of phosphorus if manure has been digested in the past through microbes, an increasingly common practice that also reduces greenhouse fuel emissions, and 39% otherwise. struvitate every day, which means that in one year, 8 animals can supply enough phosphorus to fertilize an acre of crops.
Estruvite is one of the many promising phosphorus fertilizers for recycling human and animal waste. And it has many advantages: it’s portable; It involves pathogens or other contaminants that are not unusual in waste; and, according to Harrison, it works very well as fertilizer. “Manufacturers of alfalfa, they need it,” he says.
Ostara has been testing his struvite, announced crystal green, for 15 years, with encouraging results. His trials found that when combined with traditional fertilizers, estruvite increases yields in many crops, adding canola and potatoes, says Ahren Britton, Ostara’s leading generation officer and manufacturers have noticed. “Frankly, the order for the product has exceeded the amount we can recover,” he says. (Harrison’s cellular assignment partner Keith Bowers has since joined the company as a component in growing its agricultural business. . )
Ostara’s good luck and Harrison’s pilot assignment turn out that, at least on a small scale, it is imaginable to reconnect the phosphor cycle. And for wastewater treatment plants, it is economical; under white water regulations, they will already have to eliminate excess phosphorus before discarding the effluent, but for farmers, most of whom are not subject to similar rules, phosphorus recovery is only an additional cost, according to Jay Gordon, Washington’s chief policy director. State Dairy Federation. ” There’s anything there,” says Gordon, who joined Harrison and me at the study center. But it’s a Rubik’s cube.
Gordon tried to negotiate water quality industry agreements in which cities would pay local farmers to reduce runoff, with little success. Earlier this year, he took another approach: while organizing a stopover in state dairy for Starbucks executives, Gordon recommended adding phosphorus to the company’s new sustainable progression program. “It’s a global and national food security problem,” Gordon told them. And farmers can be a component of the solution. “I’d like to see each and every dairy grower as a small miniature fertilizer plant,” he says. (When contacted, a Starbucks representative was unable to provide any information about the effect of Gordon’s speech. )
For now, however, the cellular recycling unit remains inactive. Harrison said farmers in other states had expressed interest in reviewing the system, but the pandemic stopped operations and he will retire in the spring.
In his box lab, Harrison shows me a pile of giant cardboard cylinders filled with sand, each with the squeeze of a single dairy. The allocation did not generate enough to supply Harrison’s alfalfa advertising manufacturers in mind; however, it estimates that there is approximately one ton of fertilizer stored in this shed.
“To be a smart guy, I’d have to locate a house for that,” he says, but admits he’s already started throwing some away. Gordon, who runs a 600-acre farm, should let go of a cry of surprise. He sold his dairy herd a few years ago and now grows corn, melon and alfalfa, among other crops. And he rejoices at the mention of loose phosphorus: “I know exactly where you can go. “
The UK report is supported by a scientific research and journalism grant from the European Geosciences Union.