Origin of giant bloom discovered

Scientists have discovered the source of the gigantic green tide of algae that almost derailed the Beijing Olympics sailing regatta.

The huge algal bloom was triggered by a rapid expansion of farmed seaweed almost 200km down the coast, satellite images reveal.

The green tide then grew and grew as it moved closer to the regatta city of Qingdao.

At one point, it became the largest ever recorded anywhere in the world.

Initially, the international media and many scientists suggested that excess nutrients (eutrophication) in coastal waters caused the algal bloom.

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