Recent Acceleration of Wetland Accretion and Carbon Accumulation Along the U.S. East Coast

Abstract

The long‐term stability of coastal wetlands is determined by interactions among sea level, plant primary production, sediment supply, and wetland vertical accretion. Human activities in watersheds have significantly altered sediment delivery from the landscape to the coastal ocean, with declines along much of the U.S. East Coast. Tidal wetlands in coastal systems with low sediment supply may have limited ability to keep pace with accelerating rates of sea‐level rise (SLR). Here, we show that rates of vertical accretion and carbon accumulation in nine tidal wetland systems along the U.S. East Coast from Maine to Georgia can be explained by differences in the rate of relative SLR (RSLR), the concentration of suspended sediments in the rivers draining to the coast, and temperature in the coastal region. Further, we show that rates of vertical accretion have accelerated over the past century by between 0.010 and 0.083 mm yr−2, at roughly the same pace as the acceleration of global SLR. We estimate that rates of carbon sequestration in these wetland soils have accelerated (more than doubling at several sites) along with accelerating accretion. Wetland accretion and carbon accumulation have accelerated more rapidly in coastal systems with greater relative RSLR, higher watershed sediment availability, and lower temperatures. These findings suggest that the biogeomorphic feedback processes that control accretion and carbon accumulation in these tidal wetlands have responded to accelerating RSLR, and that changes to RSLR, watershed sediment supply, and temperature interact to determine wetland vulnerability across broad geographic scales.

Responses of Coastal Wetlands to Rising Sea-Level Revisited: The Importance of Organic Production

“…4), resulting in a new equilibrium. Rates of elevation gains in U.S. East Coast marshes have risen during the past century as SLR has accelerated (Weston et al 2023), which suggests that these marshes have been on the positive side of the growth curve or the side of suboptimal depth. If the depth below MHW of the marsh surface is greater than optimal, an increase in the rate of SLR will depress primary production and raise the inorganic sediment input, decreasing sediment LOI.…”

The Coastal Carbon Library and Atlas: Open source soil data and tools supporting blue carbon research and policy

“…Data releases included a title, abstract, keywords, authors, associated publications, acknowledgment of funding sources, data files, and ecological meta‐data language (EML)‐style metadata, an HTML version of the metadata, and a citable digital object identifier (DOI). We published 27 datasets in this way (Abbott, Quirk, & Delaune, 2019; Allen et al., 2022; Arias‐Ortiz, Masqué, et al., 2021; Belshe et al., 2019b; Boyd et al., 2019; Breithaupt et al., 2019, 2020; Buffington et al., 2020; Callaway et al., 2019; Carlin et al., 2021; Doughty et al., 2019; Ensign et al., 2021; Fell et al., 2021; Kauffman et al., 2020b; Kemp et al., 2020; Keshta et al., 2020; Lagomasino et al., 2020; McTigue et al., 2020; Messerschmidt & Kirwan, 2020; Nolte, 2020; Peck et al., 2020a; Poppe & Rybczyk, 2019; Sanbor & Darwyn, 2020; St. Laurent et al., 2020b; Thom, 2019; Vaughn et al., 2021; Weston et al., 2022).…”

“…We published 27 datasets in this way Allen et al, 2022;Belshe et al, 2019b;Boyd et al, 2019;Breithaupt et al, 2019Breithaupt et al, , 2020Buffington et al, 2020;Callaway et al, 2019;Carlin et al, 2021;Doughty et al, 2019;Ensign et al, 2021;Fell et al, 2021;Kauffman et al, 2020b;Kemp et al, 2020;Keshta et al, 2020;Lagomasino et al, 2020;McTigue et al, 2020;Messerschmidt & Kirwan, 2020;Nolte, 2020;Peck et al, 2020a;Poppe & Rybczyk, 2019;Sanbor & Darwyn, 2020;St. Laurent et al, 2020b;Thom, 2019;Vaughn et al, 2021;Weston et al, 2022).…”

Combating Climate Change and Global Warming for a Sustainable Living in Harmony with Nature

“…The rise in sea level not only encroaches on territories of coastal communities but also contributes to seawater intrusion on freshwater systems in coastal areas. Coastal wetlands are critical to Earth's ecosystem which is becoming increasingly vulnerable in the face of rising sea levels [6] . Recently, at the COP26 meeting in Glasgow, representatives of some 1.2 billion people, from the Climate Vulnerable Forum (CVF) consisting of countries from Latin America, Africa, Asia, the Caribbean, and the Pacific were pushing the rest of the world to accept the idea of keeping the rise in global temperatures to under 1.5 ºC.…”

“…Human activities such as industries, electric power generation by coal, agriculture, and transportation are the four top sources of GHGs which are responsible for almost all of the increase in greenhouse gases in the atmosphere over the last 150 years [5] . More pieces of evidence are seen in recent times about human-induced climate change [6] . Deforestation, agriculture, and the use of fossil fuels are the primary sources of CO 2 .…”