Abstract
Sea level rise alters coastal carbon cycling by driving the rapid migration of coastal ecosystems, salinization of freshwater systems, and replacement of terrestrial forests with tidal wetlands. Wetland soils accumulate carbon (C) at faster rates than terrestrial soils, implying that sea level rise may lead to enhanced carbon accumulation. Here, we show that carbon stored in tree biomass greatly exceeds carbon stored in adjacent marsh soils so that marsh migration reduces total carbon stocks by ∼50% in less than 100 years. Continued marsh soil carbon accumulation may eventually offset forest carbon loss, but we estimate that the time for replacement is similar to estimates of marsh survival (i.e., centuries), which suggests that forest C may never be replaced. These findings reveal a critical C source not included in coastal C budgets driven by migrating ecosystems and rapidly shifting allocations between carbon stored in soils and biomass.
Keywords: marsh forest boundary,carbon storage,Chesapeake Bay,sea level rise
Authors
Associated Publication
Smith, Alexander, and Kirwan, Matthew. Sea Level-Driven Marsh Migration Results in Rapid Net Loss of Carbon. Geophysical Research Letters. 48, 13 (2021). https://doi.org/10.1029/2021GL092420
Funding
The Dominion Energy Charitable Foundation (Richmond Virginia), the U.S. National Science Foundation (LTER 1237733, CAREER 1654374), and the U.S. Department of Energy Terrestrial Ecosystem Science Program (DE-SC0021112, DE-SC0019110) funded this project. This is contribution no. 4025 of the Virginia Institute of Marine Science.
Data Publication
This data publication was assembled and published by the Coastal Carbon Research Coordination Network through the Smithsonian Institution Figshare repository. Please direct any comments or inquiries to CoastalCarbon@si.edu.
Start Date: 2019-06-01
End Date: 2019-08-31
Physical: Smith_and_Kirwan_2021_methods.csv
Physical: Smith_and_Kirwan_2021_cores.csv
Physical: Smith_and_Kirwan_2021_depthseries.csv
Intellectual Rights
This dataset is listed under a Creative Commons BY 4.0 and can be used with attribution.