World - Drowning Salt Marshes Threaten Coastal Communities
Climate change and rising sea levels are breaking down the ecosystems that protect coastal communities and their threshold for recovery is lower than previously thought, report researchers.
Salt marshes and other ecosystems act as barriers against storm surges and natural disasters for coastal communities around the world. The resiliency of these natural barriers normally allows them to continue to function and protect the communities they separate from the sea.
Now, engineers are taking a deeper look into the fundamentals of coastal ecosystems and how Engineering With Nature elements can fortify and, in some cases, recreate these vital protections.
“For these coastal ecosystems to be more useful in engineering applications, we need to know how they respond, how they adapt, how easy they are restored, and, in case they fail, how easy it is to create them,” says Orencio Duran Vinent, assistant professor in the ocean engineering department at Texas A&M University.
Salt marshes are some of the most valuable and vulnerable ecosystems in the world. Using a simplified formulation for sediment transport, the new research identified that the marshes don’t need to completely fall beneath rising sea levels to begin degrading, but instead begin to fragment and drown piece by piece at a lower water level.
“Every ecosystem that adapts to external conditions has a limit of adaptation, a threshold above which they don’t really adapt anymore, and they drown or disappear,” says Duran Vinent. “In the case of ecosystems that are adapting to rising sea levels, the threshold is dependent on how fast the sea level is rising. If they’re able to keep above the water, then they restore themselves and stay healthy.”