Can Coastal Habitats Rise to the Challenge? Resilience of Estuarine Habitats, Carbon Accumulation, and Economic Value to Sea-Level Rise in a Puget Sound Estuary

Abstract

Sea-level rise (SLR) and obstructions to sediment delivery pose challenges to the persistence of estuarine habitats and the ecosystem services they provide. Restoration actions and sediment management strategies may help mitigate such challenges by encouraging the vertical accretion of sediment in and horizontal migration of tidal forests and marshes. We used a process-based soil accretion model (Coastal Wetland Equilibrium Model) combined with a habitat classification model (MOSAICS) to estimate the effects of SLR, suspended sediment, and inland habitat migration on estuarine habitats, soil carbon accumulation, and economic value of climate change mitigation of carbon accumulation (social cost of carbon dioxide) in a macrotidal estuary in the northwest USA over 100 years (2011 to 2110). Under present-day sediment levels, we projected that after 100 years, most high salt marsh would remain with < 100 cm SLR, but substantial area converted to transitional (low) salt marsh and mudflat with ≥ 100 cm SLR. Increasing sediment availability increased the projected resilience of transitional salt marsh to SLR but did not prevent declines in high marsh area. Projected total carbon accumulation plateaued or declined with ≥ 100 cm SLR, yet the economic value of carbon accumulation continued to rise over time, suggesting that the value of this ecosystem service was resilient to SLR. Doubling or tripling sediment availability increased projected carbon accumulation up to 7.69 and 14.2 kg m−2 and increased total economic value up to $373,000 and $710,000, respectively. Allowing marsh migration supported conversion of upland to freshwater marsh, with slight increases in carbon accumulation. These results inform climate adaptation planning for wetland managers seeking to understand the resilience of estuarine habitats and ecosystem services to SLR under multiple management strategies.

Cap. 27: Noroeste. En: La Quinta Evaluación Nacional del Clima

“…La restauración de las llanuras aluviales que sirven de hábitat al salmón 194 también beneficia a los seres humanos al reducir la exposición actual y futura de la agricultura y las infraestructuras a las inundaciones provocadas por los efectos combinados del aumento del nivel del mar, las marejadas ciclónicas y la escorrentía de los arroyos 195,196 . Como en las décadas recientes se han eliminado varias presas y otros obstáculos a las áreas históricas de desove, en algunos casos los peces han recolonizado rápidamente los nuevos hábitats accesibles 197,198,199,200 .…”

“…Existe amplia evidencia de que la conservación de la diversidad genética y la protección y restauración ecológicas pueden beneficiar los procesos de los ecosistemas y aumentar la capacidad de adaptación de las especies 120,121,122,192,193,194,195,196 . Por ejemplo, la restauración mediante la eliminación de presas y estructuras infranqueables en todo el Noroeste ha restablecido algunos procesos ecológicos e hidrológicos naturales que permiten a los peces anádromos acceder a su hábitat histórico 194,197,198,199,200 .…”

Nisqually River Delta—Humans and nature benefiting together

“…Using a wetland elevation model, a habitat model, and many types of data collected in wetlands, scientists found that with more than 1 meter of sea level rise, most salt marsh may transition to sparsely vegetated marsh or mudflat and that the rate of carbon accumulation would decline. 5 Without management intervention, the projected loss of tidal marsh and forested habitat resulting from sea level rise could also affect the base of the salmon food web and salmon growth throughout the estuary. Because Chinook salmon are one of the most estuarine-dependent salmonids, substantial declines in estuarine habitat would imperil this native and highly prized cultural resource.…”

Physiological responses of scallops and mussels to environmental variability: Implications for future shellfish aquaculture

“…However, anthropogenic disturbances at global to watershed scales across the last two centuries have caused dramatic changes in temperature, fluctuations in the thermocline, shoaling of the aragonite saturation horizon, and reduced dissolved oxygen (DO) with depth in marginal seas (Feely et al, 2012). Rising atmospheric CO2 concentration is predicted to result in warmer ocean temperatures, hypoxia, ocean acidification (OA), and extreme weather (Gruber et al, 2012;Melzner et al, 2011;Moritsch et al, 2022;Rykaczewski and Dunne, 2010). OA is the process in which increased levels of atmospheric CO2 dissolve into the ocean resulting in a more acidic environment (Jiang et al, 2023).…”