Potential methane production in oligohaline wetlands undergoing erosion and accretion in the Mississippi River Delta Plain, Louisiana, USA

Sediment Addition Leads to Variable Responses in Temperate Salt Marsh Greenhouse Gas Fluxes During the Growing Season

“…These aerenchyma tissues also serve as a conduit for CH 4 transport from the rhizosphere to atmosphere (Comer‐Warner et al., 2022) and thus it is possible that this shift in vegetation composition may play a role in increased CH 4 efflux from the TLP plots. Lastly, related studies report that degraded or disturbed vegetated coastal ecosystems were likely to have greater CH 4 fluxes than restored or pristine systems (Al‐Haj & Fulweiler, 2020; He et al., 2023; Rosentreter et al., 2021). The observed CH 4 fluxes in the TLP plots (TLP‐7 cm: 35.7 μmol m −2 hr −1 , TLP‐14 cm: 19.8 μmol m −2 hr −1 ) were on average 1.5 to 4.4 times greater than averages reported for polyhaline marshes Al‐Haj and Fulweiler (2020): 9.33 μmol m −2 hr −1 ; Poffenbarger et al.…”

“…These aerenchyma tissues also serve as a conduit for CH 4 transport from the rhizosphere to atmosphere (Comer-Warner et al, 2022) and thus it is possible that this shift in vegetation composition may play a role in increased CH 4 efflux from the TLP plots. Lastly, related studies report that degraded or disturbed vegetated coastal ecosystems were likely to have greater CH 4 fluxes than restored or pristine systems He et al, 2023;Rosentreter et al, 2021) As salt marshes are valued for their carbon sequestration function and their ability to have a net cooling impact on the atmosphere, we wanted to understand how TLP might alter this capacity. Because we only measured during the day from June-October this analysis only reflects daytime, growing season dynamics and isn't representative of annual GHG dynamics.…”