Carbon storage potential in a recently created brackish marsh in eastern North Carolina, USA

Yo-Jin Shiau; Michael R. Burchell; Ken W. Krauss; Stephen W. Broome; Francois Birgand

doi:10.1016/j.ecoleng.2018.09.007

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Carbon storage potential in a recently created brackish marsh in eastern North Carolina, USA

Yo-Jin Shiau·Michael R. Burchell·Ken W. Krauss·Stephen W. Broome·Francois Birgand

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Abstract

Carbon (C) sequestration through accumulated plant biomass and storage in soils can potentially make wetland ecosystems net C sinks. Here, we collected GHG flux, plant biomass, and litter decomposition data from three distinct vegetation zones ( Spartina alterniflora , Juncus roemerianus and Spartina patens ) on a 7-year-old created brackish marsh in North Carolina, USA, and integrate these data into an overall C mass balance budget. The marsh fixed an average of 1.85 g C m −2 day −1 through plant photosynthesis. About 41–46% of the fixed C remained in plants, while 18.4% of the C was decomposed and released back to the atmosphere as CO 2 and CH 4 , and 8.6–13.2% of the decomposed C was stored as soil C. In all, this created marsh sequestered 28.7–44.7 Mg CO 2 year −1 across the 14 ha marsh. Because the brackish marsh emitted only small amounts of CH 4 and N 2 O, the CO 2 equivalent emission of the marsh was −0.87 to −0.56 g CO 2-eq m −2 day −1 , indicating the marsh has a net effect in reducing GHGs to the atmosphere and contributes to cooling. However, resultant CO 2 credit (through the increment of soil C) would be worth only $30.76–$47.90 USD per hectare annually, or $431–$671 per year for the project, which, coupled with other enhanced ecosystem services, could provide landowners with some additional economic incentive for future creation projects. Nevertheless, C mass balance determinations and radiative cooling metrics showed promise in demonstrating the potential of a young created brackish marsh to act as a net carbon sink.

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Ecological Engineering Article

Source-reported bounding extent: 34.56764471968292° to 35.0906979730151° latitude; -76.937255859375° to -76.146240234375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Yo-Jin Shiau, Michael R. Burchell, Ken W. Krauss, Stephen W. Broome, Francois Birgand. 2019. Carbon storage potential in a recently created brackish marsh in eastern North Carolina, USA. https://doi.org/10.1016/j.ecoleng.2018.09.007

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