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On the edge of Namibia’s Namib Desert, so-called fairy circles, or bare land forming patterns that stretch for miles, can be found.
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Round disks of barren soil, known as “fairy circles,” look like rows of polka dots stretching for miles above the ground. The mysterious origins of this phenomenon have intrigued scientists for decades, but the phenomenon may be much more widespread than once thought.
Fairy rings had previously only been found in the arid regions of the Namib Desert in southern Africa and the outback of Western Australia. But a new study used artificial intelligence to identify vegetation patterns resembling fairy rings in hundreds of new locations across 15 countries on three continents. This could help scientists understand fairy rings and their formation on a global scale.
New research will be published Monday in the journal Proceedings of the National Academy of Sciencesresearchers analyzed a dataset containing high-resolution satellite imagery. dry land, or arid ecosystems with little precipitation, from around the world. Neural networks, a type of AI that processes information in a similar way to the brain, were used to search for patterns similar to fairy rings.
“This is the first time that the use of artificial intelligence-based models on satellite imagery has been done at scale to detect fairy ring-like patterns,” said study lead author and director of the Interdisciplinary Environmental Research Institute. said data scientist Dr. Emilio Guillard. Research at the University of Alicante, Spain, via email.
First, the study authors trained a neural network to recognize fairy rings by feeding them more than 15,000 satellite images taken over Namibia and Australia. The fairy ring was visible in half of the images and not in the remaining images. The scientists then fed the AI with a dataset containing satellite images of about 575,000 plots of land around 2.5 acres (1 hectare) around the world. Neural networks scanned the vegetation in these images, identifying repeating circular patterns similar to known fairy circle patterns, and evaluating the size, shape, and location of the circles, as well as the density and distribution of the patterns.
The output of this analysis then required human review, Gilad said. “Based on the interpretation of the photographs and the local conditions, we had to manually discard several man-made and natural structures that were not fairy circles,” he explained.
The results showed 263 dry areas in Namibia and Australia with a circular pattern resembling a fairy wheel. These arid regions were distributed throughout Africa (Sahel, Western Sahara, and Horn of Africa), and were also concentrated in Madagascar and central-western Asia, and central and southwestern Australia.
Fairy circles aren’t the only natural phenomenon where round bare spots repeatedly appear in the landscape. Dr. Stefan Getzin, a researcher in the Department of Ecosystem Modeling at the University of Göttingen in Germany, said one of the factors that distinguishes fairy circles from other types of vegetation gaps is the strong and orderly pattern between the circles. .
Getzin et al. published a paper in November 2021 fairy circle definition and what made them unique, he told CNN in an email, highlighting the details of the overall pattern structure. And Getzin, who was not involved in the latest research, says the newly discovered pattern is insufficient.
“Fairy rings, in principle, Ability to form “spatially periodic” patternsThis is “remarkably more orderly” than other patterns, Goetzin said, and none of the patterns in the study cleared that high bar.
But in reality, Gilad says, there is no universally accepted definition of a fairy ring. By referencing guidelines established in multiple published studies, he and his co-authors measured the size and shape of individual circles, and the patterns they collectively form, to identify potential fairy I have identified the circle. These spatial pattern indicators are “virtually the same” in the old and new fairy worlds, he said.
Some of the new locations identified were met by Dr Fiona Walsh, who has been researching fairy rings in the Australian outback as part of an international team. “The distribution pattern in Australia appears to be consistent with some of what we have previously reported,” Walsh said. Ethnoecologist at the University of Western Australia. Mr. Walsh is not involved in the new investigation.
The study authors also compiled environmental data from where the circles were found and collected evidence that might suggest what caused them to form. The researchers determined that fairy circle-like patterns are most likely to occur in very dry, sandy soils that are highly alkaline and low in nitrogen. Scientists also found that fairy circle-like patterns help stabilize ecosystems, making regions more resilient to disturbances such as floods and extreme droughts.
But the question, “What is the shape of a fairy circle?” is complex, and the factors that produce fairy circles may vary from site to site, the study authors reported. Getzin previously said in an email that certain climatic conditions and plant self-organization generate fairy circles in Namibia, and that while insects such as termites take advantage of dry areas, their activity does not directly create the patterns. Stated. .
But Mr Walsh said Australian fairy rings were closely linked to termite activity.of their team the studyResearch carried out in close collaboration with Indigenous peoples has shown that in Western Australia and the Northern Territory, termites are essentially involved in the functioning of fairy circles, known as ‘liniji’ in Manjirijara and ‘minkiri’ in Walpiri. She said it turned out that there were. Email from CNN.
“Aboriginal people have described these patterns since at least the 1980s and said they’ve known them for generations, perhaps thousands of years,” Mr Walsh said.
“In Australia, termites don’t just ‘play a role’,” she added. “Those are the key mechanisms, and interpretation must center on termite, grass, soil, and water dynamics.”
Many questions about fairy circles remain unanswered, and the authors of the new study are optimistic that their global atlas will open a new chapter in the study of these strange wastelands.
“We hope that the information we present in our paper will provide scientists around the world with a new area of research that will solve new puzzles in the formation of fairy ring patterns,” Gilad said.
Mindy Weisberger is a science writer and media producer whose work has appeared in Live Science, Scientific American, and How It Works magazines.