Factbox - Why oceans are key to the global economy

(Reuters) - Oceans carry the bulk of the world's trade, are a major source of food and employment and help regulate the planet's climate but they are under threat from pollution, over-fishing and global warming.

Governments and businesses are increasingly aware of the value of oceans but are struggling to address the many threats that imperil seas around the globe. The World Bank is steering a new global alliance on the issue.