Scientists have found the cause of mysterious stains round shape, surrounded by vegetation, which are called “witches circles”.
Such spots are found in some arid parts of the Earth, their size varies from 2 to 35 meters.
These huge, symmetrical patches of dry land has interested scientists for many years, when they were first discovered in the Namib desert, and then in the Australian deserts. The researchers suggested that the circles could be because of termites that eats the roots of plants, or from lack of water.
A recent study conducted in the Namib desert scientists from Indiana University showed that the cause of the “witch circles” is a shortage of water. The researchers took detailed measurements of the rate of water infiltration, the level of soil moisture carried out the biometrics grass of several circles. The measurements showed that inside of such circles is less than the edges causing the vegetation naturally grows along the edges of the circles.
As for the version with the termites, scientists have discovered the circles, near which there was not only termites, but even traces of their activities. Researchers believe that in other places the termites are attracted to moisture and vegetation, but to the formation of the circles themselves are not involved.
Scientists still can not exactly say, as a result of the circle are smooth, perhaps this is due to the geological characteristics of specific places, but as they with great confidence call it a shortage of water, not insect activity.
© 2017, paradox. All rights reserved.
