Iron wet deposition in the coastal zone of the Gulf of Gdansk [Poland]

The concentrations of total iron were determined in the 30 rainwater samples collected at Gdynia station, located in the coastal zone of Gulf of Gdansk. The samples were assembled from December 2002 to November 2003. Total iron concentrations were measured using a colorimetric method with bathophenanthroline. The concentrations of major rain components (Na⁺, NO₃⁻-, Cl⁻, SO₄²⁻) were also determined. Concentrations of Fetot ranged from 0.26 μg·dm⁻³ to 0.51·10⁻³ μg·dm⁻³. The total annual flux of Fetot was 11.22 mg·m⁻²yr⁻¹, which suggests that wet deposition can be one iron source for phytoplankton in the Southern Baltic. Iron in rain came from both terrestrial areas and seawater. Particularly at E&SE winds the swash zone saturated with marigenic aerosols was a significant source of iron. In these causes an anthropogenic influence on rain acidification was found to be minimal.