Constraints on the adjustment of tidal marshes to accelerating sea level rise

Neil Saintilan; Katya E. Kovalenko; Glenn R. Guntenspergen; Kerrylee Rogers; James C. Lynch; Donald R. Cahoon; Catherine E. Lovelock; Daniel A. Friess; Erica Ashe; Ken Krauss; Nicole Cormier; Tom Spencer; Janine Adams; Jacqueline Raw; Carles Ibanez; Francesco Scarton; Stijn Temmerman; Patrick Meire; Tom Maris; Karen M. Thorne; John Brazner; Gail L. Chmura; Tony Bowron; Vishmie Palepitiya Gamage; Kimberly Cressman; Charlie Endris; Christina Marconi; Pamela Marcum; Kari St. Laurent; William G. Reay; Kenneth B. Raposa; Jason A. Garwood; Nicole Kahn

doi:10.1126/science.abo7872

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Constraints on the adjustment of tidal marshes to accelerating sea level rise

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Abstract

Much uncertainty exists about the vulnerability of valuable tidal marsh ecosystems to relative sea level rise. Previous assessments of resilience to sea level rise, to which marshes can adjust by sediment accretion and elevation gain, revealed contrasting results, depending on contemporary or Holocene geological data. By analyzing globally distributed contemporary data, we found that marsh sediment accretion increases in parity with sea level rise, seemingly confirming previously claimed marsh resilience. However, subsidence of the substrate shows a nonlinear increase with accretion. As a result, marsh elevation gain is constrained in relation to sea level rise, and deficits emerge that are consistent with Holocene observations of tidal marsh vulnerability.

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Neil Saintilan, Katya E. Kovalenko, Glenn R. Guntenspergen, Kerrylee Rogers, James C. Lynch, Donald R. Cahoon, Catherine E. Lovelock, Daniel A. Friess, Erica Ashe, Ken Krauss, Nicole Cormier, Tom Spencer, Janine Adams, Jacqueline Raw, Carles Ibanez, Francesco Scarton, Stijn Temmerman, Patrick Meire, Tom Maris, Karen M. Thorne, John Brazner, Gail L. Chmura, Tony Bowron, Vishmie Palepitiya Gamage, Kimberly Cressman, Charlie Endris, Christina Marconi, Pamela Marcum, Kari St. Laurent, William G. Reay, Kenneth B. Raposa, Jason A. Garwood, Nicole Kahn. 2022. Constraints on the adjustment of tidal marshes to accelerating sea level rise. https://doi.org/10.1126/science.abo7872

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