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7 major threats to our planet's oceans

Mangroves in Boca Chita Key, Fla.

Photo: caitelle/Flickr

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Mangrove destruction

Mangroves, like this one located in Boca Chita Key, Fla., are often considered the "backbone" of the tropical ocean coastlines for their essential role in supporting water quality, promoting biodiversity among fish and protecting coastal areas against erosion and storms.