Back in 2017, Anna E. Braswell conducted research for her dissertation, in which she and her co-author, James B. Heffernan, examined hundreds of coastal tidal marshes along the U.S. Atlantic and Gulf coasts in order to determine the factors that prohibit wetland spread and establish their resilience to alterations.

What they found was that the estuary's depth, size, shape, latitude and surrounding geography, in conjunction with the shape and orientation of the nearby coastline and depth of near-shore waters, all play a part in indicating how well the marsh could resist change. Additionally, the amount of "replenishing sediment" being carried into the estuary was also a key indicator observed as well.

"These macro-scale coastal and watershed characteristics accentuated or limited the stabilizing impacts of the local feedbacks," Braswell said in an article found on phys.org" onclick="window.open(trackOutboundLink('https://phys.org'); return false;)" target="_blank">phys.org. "But they weren't really evident until we took a few steps back and viewed the estuaries from broader spatial perspectives."

Heffernan relates that it is important to know these characteristics because it is a crucial step in understanding which marshes are more susceptible to environmental impacts later in the future.

"Knowing what causes these tipping points to vary from location to location is an important step in identifying where we should expect marshes to be especially vulnerable to future change," he said in the aforementioned article. "It also provides a framework for understanding where wetland restoration is likely or not likely to succeed."

The researchers' dissertation appeared in a journal called Ecosystems, which is available for purchase for $39.95, and can be accessed by visiting the site linked at the bottom of the phys.org article HERE.