To her fans, DJ and music producer Jayda Guy is the Grammy-nominated artist spinning propulsive dance beats at some of the world’s biggest festivals.

But in a new documentary, Guy returns to her “nerdy” roots as a marine scientist — bringing viewers on a journey to explore one of nature's most potent climate allies: blue carbon.

That’s the planet-warming carbon trapped in the soil and silt of mangroves, salt marshes and seagrass meadows that fringe nearly every continent on Earth. These ecosystems cover just 2 percent of the ocean’s surface, yet they account for half of all the carbon buried in it .

The film, “Blue Carbon: Nature’s Hidden Power,” executive-produced by Conservation International, explores the threats facing blue carbon ecosystems and the people working to protect them.…