Deciphering As and Cu cycling in sediment pore waters in a large marina (Port Camargue, southern France) using a multi-tracer (Fe, Mn, U, Mo) approach

In the sandy layer, Fe, Mn, Mo and As were released into solution and diffused toward the top of the profile. They precipitated at the boundary between the muddy and sandy layers. This precipitation accounts for the high (75 μg g−1) As concentrations measured in the sediments at a depth of 24 cm.