Decode the fairy circles in Danish waters

Researchers found the cause of forming a series of fairy circles scattered across the seabed off Denmark.

Circles shaped like bright oval ovals in the Mediterranean and Baltic seabed are the result of uninhabited bare land between the seagrass, Science Advances on 2 August. . According to the researchers, bare circles caused by foreign organisms are a sign of an endangered ecosystem.

Picture 1 of Decode the fairy circles in Danish waters
Fairy circle under the Danish sea.(Photo: Science Advances).

Circles are found around the Danish coast as well as the Balearic Islands, including Mallorca. Invasive species are pushed to these areas due to pollution and climate change, according to the research team at the University of Baleares Islands in Palma, Mallorca.

"The spatial arrangement of plant populations is an important factor in assessing the healthy development and functioning of ecosystems," said Daniel Ruiz-Reynés, the team leader. "This factor acts as a guiding sign of climate impacts or people on ecosystems."

"The fairy circles indicate the seagrass with scientific name Posidonia oceanica in the affected area is at risk. Decreasing seagrass populations can significantly change larger ecosystems , " the research team said. save sharing.

According to Ruiz-Reynés, the number of circles is much larger than scientists know because they hide under the sea."Satellite images and geomorphologic images reveal complex seascape including many pastures Posidonia oceanica, proving that circles can be popular but still mostly hidden under the sea," Ruiz-Reynés said.

Although seagrass around Mallorca is a highly prolific species, their slow growth of several centimeters per year means it is impossible to restore the amount of lost grass. The team used a mathematical model based on the growth rate of seagrass and interacting at a distance between aquatic plants. They concluded that competition for source resources was a key factor leading to the creation of the fairy circle.

Picture 2 of Decode the fairy circles in Danish waters
The fairy circles are up to 15m wide formed from eel.(Photo: Jacob T. Johansen).

A study in 2014 explored the origin of similar fairy circles found in the distribution area of ​​another aquatic plant also located off Denmark. The strange circles of water formed by eel , up to 15 meters wide, are the result of poisoning.

Danish biologists have confirmed that circles are not related to bomb craters and are not traces of alien landing. They thought that the fairy circle formed from naturally occurring eels in a circle and poison that killed weak old algae roots.

The study results of mud around the circles indicate that the amount of highly toxic sulphide with eel accumulates gradually in the seabed. This poison can be made from agricultural pollutants that leak into the water, according to NBC News.


The fairy circle in Namibia.(Video: New Scientist).

The name of the underwater fairy circle was set by the team according to the scattered circular spaces in the Namibia grassland. In January, a group of scientists at Princeton University discovered the cause of forming millions of these rings. They are caused by a combination of behavior of plant and insect populations.