What ecological effects does a foreshore suppletion, and a beach suppletion, have on the marine ecosystem in the intertidal and shallow surf zone (<6 m depth)? The foreshore suppletion (400.000m³) was by means of an experimental set-up in the shallow coastal zone (-1 to -2m TAW) of Mariakerke. Beside it, a beach nourishment was conducted at Mariakerke (681243m³) and Middelkerke (968754m³). For the Mariakerke area, we collect biological and sedimentological samples in the impact area and in a control area (Bredene), before as after the suppletion, whereas for Middelkerke only the data after suppletion was part of the study. We monitor the marine ecosystem with a focus on the fauna within the sediment (macrofauna) and on the sediment (hyperbenthos, epi- and demersal fish fauna) in the intertidal zone and subtidal zone.