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Kevin Sanders

Unusual 'Fairy Circles' Found Outside Africa for the First Time

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Kevin Sanders

Strange, circular bald spots called "fairy circles" have been found in Australia, which marks the first time the phenomenon has been seen outside of Africa. Researchers say soil and plants created the circles themselves, and the theory of these origins has been published in the Proceedings of the National Academy of Sciences.

Fairy circles are open spots of naked earth in areas otherwise covered with vegetation. When they appear, they appear in droves, and they’re typically pretty big; the circles in Namibia range from 7 to almost 50 feet in diameter apiece. From the air, they look like leopard spots on the landscape. (Their unusual appearance may even trigger trypophobia in some observers.)

Where do fairy circles come from? That depends on whom you ask. Two culprits are most commonly suggested: bugs and gas. The bug theorists say the spots are areas where the tiny bites of ants and termites have killed the grass. As evidence, they point to the fact that Africa’s fairy circles are indeed all located by termite and ant colonies. Other scientists say the spots are the product of lots of carbon monoxide leaks. The gas rises out of the Earth’s crust, they say, killing all the vegetation it touches.

But study author and fairy circle expert Stephan Getzin of the Helmholtz Centre for Environmental Research doesn’t buy either of these theories. He’s a believer in the self-organizing plants theory, which says that, under certain conditions, plants gravitate toward resources.

“Water is limited, and because water is limited it cannot sustain a continuous vegetation coverage,” he told Smithsonian. “So we have gaps and other patterns like labyrinths and stripes or even spots.” The self-organizing theory met with resistance for a long time. Some scientists said it wasn’t even possible. If such a thing could happen, they argued, why weren’t there fairy circles in places other than Africa?

In 2014, shortly after publishing a paper on Namibia’s circles, Getzin got an email and a photo from Bronwyn Bell, an environmental manager for a mining company. Bell had read Getzin’s paper and was sure she had seen something similar nearby. Getzin was astonished. “We couldn’t believe it,” he said. “The Namibia fairy circles are supposed to be the only ones in the world.”

Getzin assembled a team of colleagues and headed to Australia. They took soil samples, recorded detailed measurements, and snapped photos from the ground and in the air. They ran computer simulations and image analysis, looking all the while for some pattern or evidence.

Image Credit: Stephan Getzin

They found that the Australian fairy circles were identical in appearance to their Namibian counterparts, but there were some interesting differences.

For one, there were almost no ants or termites to be found. Cryptic sand termites, the prime Namibian termite suspects, don’t even exist in Australia, Getzin said in a press statement. “And the [insects] we did find have a completely different distribution pattern to the fairy circles." So much for the bug theory.

Getzin and his colleagues found that the Australian soil literally forced the plants out. In Western Australia’s intense sunlight, any earth not covered with vegetation is more or less cooked, and a hard crust forms on top. The baked earth is so hard, rain can’t get in—and no rain means no plants. It's a self-perpetuating cycle that Getzin says could explain the spots.

Smithsonian explains further:

Getzin and his team suggest that when it rains, water pools to the edges of any established gaps in vegetation, straight to the waiting roots of the plants on the gap’s edge. Those edge plants then grow bigger and put down more roots to collect even more water. That means these plants are pulling resources away from their neighbors, limiting their growth and driving the circular pattern of boom and bust.

"In Namibia, the sandy soils of the fairy circles are much more permeable and precipitation can drain away with ease," Getzin said. "The details of this mechanism are different to that in Australia, but it produces the same vegetation pattern because both systems of gaps are triggered by the same instability."

His theory bolstered, Getzin intends next to begin a worldwide search for other fairy circles.

[h/t Smithsonian]

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Switzerland Flushes $1.8 Million in Gold Down the Sewer Every Year
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Switzerland has some pretty valuable sewer systems. As Bloomberg reports, scientists have discovered around $1.8 million worth of gold in the country's wastewater, along with $1.7 million worth of silver.

Scientists at the Swiss Federal Institute of Aquatic Science and Technology examined sewage sludge and effluents, or discharged liquid waste, from 64 water treatment plants and major Swiss rivers. They did this to assess the concentrations of various trace elements, which are "increasingly widely used in the high-tech and medical sectors," the scientists explained in a press statement. "While the ultimate fate of the various elements has been little studied to date, a large proportion is known to enter wastewater."

The study, which was recently published online in the journal Environmental Science & Technology, revealed that around 94 pounds of gold makes its way through Switzerland's sewage system each year, along with 6600 pounds of silver and high concentrations of rare metals like gadolinium and niobium. For the most part, these metals don't harm the environment, researchers say.

With gold and silver quite literally flowing through their sewers, is there any way that Switzerland could turn their wastewater into wealth? Scientists are skeptical: "The recovery of metals from wastewater or sludge is scarcely worthwhile at present, either financially or in terms of the amounts which could be extracted," the release explains.

However, in the southern canton of Ticino, which is home to several gold refineries, the "concentrations of gold in sewage sludge are sufficiently high for recovery to be potentially worthwhile," they conclude.

Switzerland is famous for its chocolate, watches, and mountains, but it's also home to major gold refineries. On average, around 70 percent of the world's gold passes through Switzerland every year—and judging from the looks of it, much of it goes down the drain. As for the sewer silver, it's a byproduct of the chemical and pharmaceutical industry, which is a cornerstone of Switzerland's economy.

[h/t Bloomberg]

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Grass-Fed Beef Is Actually Worse for the Planet, Report Finds
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There are plenty of reasons to reject factory farming, but in the case of beef, your carbon footprint shouldn’t be one of them. According to EcoWatch, new research shows that grazed cattle provide an outsized contribution to greenhouse gasses, as opposed to cattle kept largely indoors and fed on grain.

The report [PDF], released by Oxford’s Food Climate Research Network, aims to provide definitive answers to what has been a heavily debated topic in environmental circles. Some research has found that grazing cattle actually reduces the carbon footprints of beef operations, because all that pasture stores carbon and prevents it from being released into the atmosphere, and because all that chomping stimulates new vegetation growth. Other research has found that the benefits aren’t as great as the grass-fed boosters estimate—especially since the fields of grain used to grow cattle feed for factory farms sequester carbon, too.

The new Oxford research comes down firmly on the side of the latter camp. It finds that while grass-fed operations can help sequester carbon, it’s “only under very specific conditions,” in part since the definition of what a grassland is can vary wildly. There are natural ranges dominated by wild vegetation, there are pastures that are actively maintained and managed by farmers, and there is land that lies somewhere in between. Overgrazing, trampling, and soil conditions can all negatively impact how much carbon the grasses can sequester. And even under the best conditions, the gains can be short-lived. “This sequestering of carbon is even then small, time-limited, reversible, and substantially outweighed by the greenhouse gas emissions these grazing animals generate,” according to FCRN.

And it seems that even if the vegetation does sequester carbon, grass-fed beef is still an outsized source of greenhouse gasses.

To begin with, all cattle are a huge drain on the environment, no matter how you feed them. The report estimates that the livestock supply chain generates around 14.5 percent of global greenhouse gas emissions, and cattle create 65 percent of those livestock emissions. But even compared to cattle in general, grass-fed animals are heavy polluters. Within the global protein supply, grass-fed beef makes up around 1 gram of protein per person, per day, compared to 13 grams from all ruminants (cattle, sheep, goats, etc.). But these grazed cattle generate up to a third of all global greenhouse emissions from ruminants. In other words, grass-eating cattle create an outsized cost—emissions-wise—compared to the meat they provide.

And the carbon sequestration doesn't help enough to offset that. The report estimates that the carbon sequestration that might occur from grazing practices would only offset emissions by 20 percent.

There are other reasons to buy grass-fed beef, of course, whether it’s about ethical concerns with factory farming or just a taste preference. But if you’re going to choose grass-fed, your reason shouldn’t be concern for the environment.

[h/t EcoWatch]

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