Kelp

New research shows we’ve long underestimated the environmental benefits from kelp forests. Now these important ecosystems are threatened. Floridians are bracing for an unwanted visitor this summer: sargassum. A 5,000-mile-long island of this rootless seaweed is floating around the Atlantic, and large swathes of it are expected to wash ashore in Florida and other states in the coming months. Smaller amounts have already arrived, and the rotting clumps of algae on the beach release hydrogen sulfide, giving off the smell of rotten eggs. A large landfall will be a health hazard — and a deterrent for tourists and nesting sea turtles alike.