Spatial patterns in soil biogeochemical process rates along a Louisiana wetland salinity gradient in the Barataria Bay estuarine system, June 2014

We sampled 3 plots (0.25m x 0.25m) at each of four sites along a salinity gradient downstream of the Davis Pond Diversion in the Barataria estuarine system in June 2014. Net soil greenhouse gas (CO2, CH4, N2O) fluxes were quantified for each plot. Live and dead above-ground and below-ground biomass was quantified from each plot except at BT4 where areal extent and average height of Avicennia germinans stand was assessed and stem and pneumatophore density determined. Biogeochemical process rates (greenhouse gas production, nitrification potential, denitrification enzyme activity (DEA), iron reduction, phosphorus sorption) and microbial community abundances were determined and soil properties were characterized for surface (0-5cm) and subsurface (10-15cm) soils at each plot. Additionally, porewater salinity and dissolved inorganic nutrient concentrations were measured.