Baltic fairy rings explained Strange formations in the eelgrass up to 15 metres across found in shal
Baltic fairy rings explained Strange formations in the eelgrass up to 15 metres across found in shallow clear water near the Danish isle of Mon over the last years have provoked much discussion over the last years, with fairies, world war 2 bombs and crop circles being amongst the offered explanations. New research published in Marine Biology suggests that they are due to the natural pattern that forms as the grass grows radially outwards and then dies when it encounters toxins in the chalky ooze of the seafloor. The mud contains high natural levels of sulphide minerals, which are known to be poisonous to these plants (though in other places human pollution from agriculture creates similar conditions). The ooze usually gets eroded away soon after deposition, but the roots of the eelgrass trap and stabilise it, concentrating the toxins around their roots. The younger healthy plants are more toxin resistant, and are found at the outer edge of the ring, while the older plants gradually die away in the centre as the toxins gradually overwhelm them. Loz Image credit: Jacob T. Johansenhttp://www.livescience.com/42985-underwater-fairy-rings-explained.html -- source link
#ocean#netherlands#science#geology