"The Marsh at the End of the World"

"Wetlands are some of the world’s greatest carbon sinks, and they're starting to rot: from Maine, an investigation of an ecosystem on the brink."

"A gnarled old pine marks the entrance to the Sprague River Marsh. It is high summer, a short season of riotous green in Maine. But the tree hasn’t taken any cues from the tilting of the planet, the long hours of sunlight, or the sudden warm spike. Its branches extend, empty and bare. This pine must be at least a hundred years old, but as with so many others I saw lining the banks of tidal marshes up and down the coast, too much salt water had too regularly soaked into the ground around the tree’s root system, killing it. On the surface, a single tree might seem inconsequential. But its death is a sign of a much larger transformation—the disintegration of tidal marshes all along the coast.

Because tidal marshes sit exactly at sea level, they are one of the first landscapes to show the effects of accelerated sea-level rise. Sometime during the past half-century or so, this tree’s taproot started to occasionally suck down salt water instead of fresh. It was stunned and stunted at first. Then it stopped growing. The sea kept kneading into the aquifer, storms got stronger and dumped more standing water onto the marsh, and it and so many other elegant old trees all along the coast—from the Sacramento-San Joaquin River Delta to the Gulf of Mexico—started to die."

Elizabeth Rush reports for Guernica September 5, 2017.