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Fairy Circles (Round Patches Of Bare Earth In Desert / Scrubland)

Have to see if I noted down the areas, honestly thought it was common in most places.
 
An update, and perhaps a breakthrough ... Field research in western Australia has finally provided empirical evidence supporting the notion that desert fairy circles are the result of a Turing pattern.


FULL STORY: https://www.sciencealert.com/myster...ained-by-alan-turing-theory-from-70-years-ago

More on Oz fairy Circles.

A small study published last month in the Australian Journal of Botany suggests that microbes living in the soil may contribute to the rings’ formation in Australia, rendering the dirt within the ring hostile to new seedlings and the dirt beyond the ring hospitable.

Spinifex grasses start out as small round hummocks, said Angela Moles, an ecologist at the University of New South Wales and an author of the new paper. Then, as new seedlings sprout outward, the plants in the middle die, leading to the ring shape. Researchers have explored whether the bare inner soil becomes depleted of nutrients; whether it is too dry or compacted for new growth; and whether insects might be destroying the spinifex. But a consensus on what is driving the formation of rings has yet to emerge.

Dr. Moles had heard of a small European swamp grass that grew in a ring pattern, a result of a buildup of soil pathogens in the middle. She and Neil Ross, a graduate student in her lab, were curious whether sterilizing the soil from inside rings, thus killing any microbial organisms there, would make it easier for plants to grow in it. If so, that would imply that microbes were involved. ...

https://www.nytimes.com/2021/04/12/science/fairy-circles-australia.html
 
More on Oz fairy Circles.

A small study published last month in the Australian Journal of Botany suggests that microbes living in the soil may contribute to the rings’ formation in Australia, rendering the dirt within the ring hostile to new seedlings and the dirt beyond the ring hospitable.

Spinifex grasses start out as small round hummocks, said Angela Moles, an ecologist at the University of New South Wales and an author of the new paper. Then, as new seedlings sprout outward, the plants in the middle die, leading to the ring shape. Researchers have explored whether the bare inner soil becomes depleted of nutrients; whether it is too dry or compacted for new growth; and whether insects might be destroying the spinifex. But a consensus on what is driving the formation of rings has yet to emerge.

Dr. Moles had heard of a small European swamp grass that grew in a ring pattern, a result of a buildup of soil pathogens in the middle. She and Neil Ross, a graduate student in her lab, were curious whether sterilizing the soil from inside rings, thus killing any microbial organisms there, would make it easier for plants to grow in it. If so, that would imply that microbes were involved. ...

https://www.nytimes.com/2021/04/12/science/fairy-circles-australia.html

My teenage years were spent living on a property that had it's own croquet court which developed a fairy ring almost overnight. It was (looking back) probably 2 metres in diameter with blotches of dead grass in a not quite perfect circle, the size of your fist. The grass never really grew back to what it had been once it's time had passed (do Fairy Rings have seasons?) and a faint outine of the circle could always be seen.
We had a gardener at the time who put it down to either a type of fungal spore in the soil or a grub that lived in the dirt.
 
An update, and perhaps a breakthrough ... Field research in western Australia has finally provided empirical evidence supporting the notion that desert fairy circles are the result of a Turing pattern.
FULL STORY: https://www.sciencealert.com/myster...ained-by-alan-turing-theory-from-70-years-ago

As of the time I posted earlier, the basis for creating a Turing pattern was related to water rather than termites:

Alternatively, scientists have proposed that fairy circles are the result of plants arranging themselves to make the most of limited water resources in a harsh, arid environment.

It sounds plausible, and if true, would also happen to be another naturally occurring example of a Turing pattern. But there's not a lot of empirical evidence to actually support the hypothesis, researchers say, because the kinds of physicists who tend to model the Turing dynamics of these systems rarely end up also conducting field work in the desert in support of their ideas.

"There is a strong imbalance between the theoretical vegetation models, their a priori assumptions and the scarcity of empirical proof that the modelled processes are correct from an ecological point of view," a team led by ecologist Stephan Getzin from the University of Göttingen in Germany explains in a new paper.

Newly reported results obtained by University of Göttingen researchers over the last two rainy seasons seem to confirm their hypothesis.

Secrets of Namibia's fairy circles demystified: Plants self-organize
Researchers show that plant water stress not termites causes mysterious circles

Date: October 20, 2022
Source: University of Göttingen

Summary:
Scientists have puzzled over the origin of Namibia's fairy circles for nearly half a century. It boiled down to two main theories: either termites were responsible, or plants were somehow self-organizing. Now, researchers benefiting from two exceptionally good rainfall seasons in the Namib Desert, show that the grasses within the fairy circles died immediately after rainfall, but termite activity did not cause the bare patches. Instead, continuous soil-moisture measurements demonstrate that the grasses around the circles strongly depleted the water within the circles and thereby likely induced the death of the grasses inside the circles. ...

FULL STORY: https://www.sciencedaily.com/releases/2022/10/221020122948.htm
 
Fairy Circles May Now Exist in 15 Countries. We Still Don't Understand Them.

Travel to certain arid landscapes throughout the world, and you’ll be greeted by a strange natural phenomenon — nearly circular patches of barren ground, otherwise surrounded by vegetation, that vary in size from seven to 40 feet in diameter.

fairy-circles-in-the-namibian-desert-royalty-free-image-1695913250.jpg


These strange formations are known as “fairy circles,” and while scientists don’t know for certain what causes them (termites is a leading theory), it was generally thought that they were only endemic to Western Australia and Namibia. Now, a new study suggests that the phenomenon is more widespread than previously believed.

The researchers trained a pattern-recognition model to recognize fairy circles across 575,000 two-and-a-half acre plots of dryland habitat worldwide. Although drylands cover 41 percent of the Earth’s surface, the model was able to pinpoint only a small percentage of that area capable of containing fairy circles. The results displayed a total of 263 sites across 15 countries and three continents, including places like Madagascar and Kazakhstan.

https://www.popularmechanics.com/science/environment/a45344919/what-are-fairy-circles/

maximus otter
 
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