The effects of crude oil on nitrogen cycling in northern Gulf of Mexico salt marshes, 2018-01-10 to 2018-06-13

This dataset was generated from a study to test the effects of crude oil on N cycling processes. We conducted a lab incubation study on salt marsh sediments from three sites subjected to differing amounts of hydrocarbon contamination following the 2010 Deepwater Horizon (DWH) oil spill. Of the three sites, the Chandeleur Islands were moderately oiled, while Dauphin Island and Dog River were not impacted by the DWH spill. Sediments were incubated with and without water accommodated fraction (WAF) of oil for 6 days, then potential rates of nitrification, denitrification, and DNRA were measured to determine if the addition of WAF impacted these pathways. The addition of WAF only impacted DNRA at Dauphin Island, in which potential rates were two-fold higher in 100% WAF than control samples (p < 0.05). In control samples, denitrification was four-fold higher at the Chandeleur Islands than Dauphin Island or Dog River (p < 0.05). There were no site differences or treatment effect on nitrification potential (p > 0.05).