Satellite data show Georgia salt marsh health decline

Scientists at UGA's Marine Institute at Sapelo Island have found that the amount of vegetation along the Georgia coast has declined significantly in the last 30 years, spurring concerns about the overall health of marshland ecosystems in the area:

Using data collected by NASA's Landsat TM 5 satellite, which provided 28 years of nearly continuous images of the Earth's surface between 1984 and 2011, the researchers found that the amount of marsh plant biomass had dropped 35 percent. They published their findings recently in the journal Remote Sensing.

This sharp decline is largely due to changes in climate, the researchers report, with prolonged periods of drought and increased temperatures playing a major role. And scientists worry that this loss of vegetation will have a ripple effect throughout the complex marsh-based ecosystems.

"A decrease in the growth of marsh plants likely affects all of the animals that depend on the marsh, such as juvenile shrimp and crabs, which use the marsh as a nursery," said Merryl Alber, director of the Marine Institute and UGA professor of marine sciences. "These decreases in vegetation may also affect other marsh services, such as stabilizing the shoreline, filtering pollutants and protecting against storm damage."

As we mentioned recently, research facilities are allowing scientists to do very difficult work over longer periods that produce more expansive, dependable and at times, worrying results. Reckoning with the effects of climate change is likely the biggest challenge ever faced. The work that researchers are doing to inform, report and teach presents our very best options for preparing for these long-term effects.

Image: Spartina grass grows in the Sapelo Island saltmarsh. (Photo credit: Amy Ware)