Atmospheric input of anthropogenic phosphorus to the northwest mediterranean under oligotrophic conditions

Phosphorus (P) concentration in the atmospheric aerosol was measured at a northwestern Mediterranean coastal site. Airborne P ranged between 25 and 85 ng m−3 (geometric mean: 51 ng m−3). Due to a significant contribution (about 90%) of anthropogenic land-based source emissions, dry deposition velocities of 0.1–0.5 cm s−1 were used to estimate a dry flux of 0.15–0.7 μmol P m−2 day−1. The theoretical impact of the dry flux on primary production (0.1–0.4 mg C m−2 day−1) is 50–200-fold lower than that of a single significant wet event. The incineration plant of the Nice district is identified as a possible major source of airborne anthropogenic P. As the implementation of waste plants is currently expanding along the western European shores, the importance of the P atmospheric source to the western Mediterranean is likely to increase with time.