Environmental controls, emergent scaling, and predictions of greenhouse gas (GHG) fluxes in coastal salt marshes
Abdul-Aziz, Omar I.
Ishtiaq, Khandker S.
Moseman-Valtierra, Serena M.
Kroeger, Kevin D.
Gonneea, Meagan E.
MetadataShow full item record
KeywordCoastal salt marshes; GHG fluxes; Environmental controls; Emergent scaling; Modeling and predictions
Coastal salt marshes play an important role in mitigating global warming by removing atmospheric carbon at a high rate. We investigated the environmental controls and emergent scaling of major greenhouse gas (GHG) fluxes such as carbon dioxide (CO2) and methane (CH4) in coastal salt marshes by conducting data analytics and empirical modeling. The underlying hypothesis is that the salt marsh GHG fluxes follow emergent scaling relationships with their environmental drivers, leading to parsimonious predictive models. CO2 and CH4 fluxes, photosynthetically active radiation (PAR), air and soil temperatures, well water level, soil moisture, and porewater pH and salinity were measured during May–October 2013 from four marshes in Waquoit Bay and adjacent estuaries, MA, USA. The salt marshes exhibited high CO2 uptake and low CH4 emission, which did not significantly vary with the nitrogen loading gradient (5–126 kg · ha−1 · year−1) among the salt marshes. Soil temperature was the strongest driver of both fluxes, representing 2 and 4–5 times higher influence than PAR and salinity, respectively. Well water level, soil moisture, and pH did not have a predictive control on the GHG fluxes, although both fluxes were significantly higher during high tides than low tides. The results were leveraged to develop emergent power law‐based parsimonious scaling models to accurately predict the salt marsh GHG fluxes from PAR, soil temperature, and salinity (Nash‐Sutcliffe Efficiency = 0.80–0.91). The scaling models are available as a user‐friendly Excel spreadsheet named Coastal Wetland GHG Model to explore scenarios of GHG fluxes in tidal marshes under a changing climate and environment.
Author Posting. © American Geophysical Union, 2018. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Biogeosciences 123 (2018): 2234-2256, doi:10.1029/2018JG004556.
Suggested CitationJournal of Geophysical Research: Biogeosciences 123 (2018): 2234-2256
Showing items related by title, author, creator and subject.
Gilbert, Jack A.; Henry, Chris (2014-09)Biological phenomena at the microbial community level encode information about the subpopulation of cells and taxa at a specific time in the succession and biogeochemical evolution of that assemblage. To capture and ...
Nowacki, Daniel J.; Ganju, Neil K. (American Geophysical Union, 2019-11-09)The growth (or decay) of salt marshes depends on suspended‐sediment flux into and out of the marsh. Suspended‐sediment concentration (SSC) is a key element of the flux, and SSC‐based metrics reflect the long‐term sediment‐flux ...
Time of Emergence of surface ocean carbon dioxide trends in the North American coastal margins in support of ocean acidification observing system design. Turk, Daniela; Wang, Hongjie; Hu, Xinping; Gledhill, Dwight K.; Wang, Zhaohui Aleck; Jiang, Liqing; Cai, Wei-Jun (Frontiers Media, 2019-03-08)Time of Emergence (ToE) is the time when a signal emerges from the noise of natural variability. Commonly used in climate science for the detection of anthropogenic forcing, this concept has recently been applied to ...