Report: “Sand withdrawal: Environmental monitoring — Dangast/Jadebusen (1996-2000)»

“Summary: From 1996 to 2000, the NLÖ Coast Research Centre managed the coast on behalf of the III. Oldenburg’s dyke tape investigates evidence retention in connection with the project “Elevation and reinforcement of the main dike from Cäciliengroden to Dangast”. For this purpose, suspended matter measurements, sedimentological and macrofaunistic studies were carried out in the area of rinsing water return in the Sander Watt in front of Cäciliengroden and in the area of eulitoral sand removal at the Dangaster outer deep. [...] The faunistic investigations revealed 81 species of macrofauna, including 15 species of fish and 2 species of the Red List. In the gutter, 74 species were recorded by grab and dredge, in the wadding area 49 Taxa by means of cutting cylinders. Due to the changing sediment ratios, increasingly slimy-loving species dominated in the study area. Obvious damage to the gutter fauna caused by the sand removal could not be detected in the examined section of the Dangaster outer depth. In the Eulitoral there were deviations in the colonisation of the cotton fauna in the near range up to 300 m around the sand collection area until the end of 1997. The area of the actual sand removal was significantly disturbed even 4 years after the completion of the sand extraction work. Species numbers, individual densities and biomass were significantly reduced compared to the status quo ante or the surrounding wattage range. The regeneration of this area will probably be a long-lasting process, in line with the forecast established in the 1994 preparatory studies, the end of which is not yet foreseen.’