Diurnal variations of carbon dioxide, methane, and nitrous oxide fluxes from invasive Spartina alterniflora dominated coastal wetland in northern Jiangsu Province

Trace gas fluxes from tidal salt marsh soils: implications for carbon–sulfur biogeochemistry

“…There are very few studies that report high temporal frequency data of CH 4 emissions, most of which include plants within their scope (via transparent chambers or eddy covariance) or focus on tidal creeks, making it difficult to ascertain whether the diel patterns seen in this study are typical of tidal salt marsh soils. Of the studies that report high temporal frequency data of plantor water-based CH 4 fluxes in coastal vegetated ecosystems, CH 4 emissions have been found to peak at various points in the day, from during the day (Yang et al, 2017(Yang et al, , 2018Tong et al, 2013), at night (Diefenderfer et al, 2018, or highly variable (Jha et al, 2014;Xu et al, 2017). At our site, CH 4 fluxes tended to peak at the confluence of peak daily temperature and low to rising tides, indicating that physical forcing may contribute to CH 4 pulses (Bahlmann et al, 2015;Middelburg et al, 1996).…”

“…N 2 O emissions and uptake loosely followed a seasonal pattern, likely driven by the canopy phenological stages. During the growing season, it has been shown that highly productive plants can compete with soil microbes for NO − 3 and NH − 4 (Cheng et al, 2007;Yu et al, 2012;Zhang et al, 2013;Granville et al, 2021;Xu et al, 2017), shifting denitrifiers into consuming N 2 O and resulting in a net uptake during G1 and M1. As the plants reach peak maturity, the system shifts into net emission of N 2 O during M2 and S1.…”