I don't have enough insight and authority to write a comprehensive statement about the message of the concert on Saturday. (The crux is that large areas of Icelandic countryside are being demolished to build dams to run new Aluminium plants to export. With other knock-on implications to the countries economy......... )
For the best explanation, follow this link to a Reykjavik publication to download and read an article and interview with Bjork who initiated this event.
(illustration from front cover by Bobby Breidholt)