The steady-state median floc size ( d
μm) of untreated flocs (green circles) and H
-treated OM-free samples (pink circles) as a function of salinity. The floc samples were collected near Atchafalaya Bay (A3 and A5) and in the Mississippi Sound near Horn Island (H1) before subjected to the laboratory experiments. The solid lines represent the linear fit to the data. The size is normalized for the OM-free steady-state median size at zero salinity. There is a clear separation between untreated and OM-free flocs for the Atchafalaya Bay samples while there is no discernible difference between untreated and OM-free floc sizes for the Horn Island sample.