|Benthic re-colonization in post-dredging pits in the Puck Bay (Southern Baltic Sea)|
|Szymelfenig, M.; Kotwicki, L.; Graca, B. (2006). Benthic re-colonization in post-dredging pits in the Puck Bay (Southern Baltic Sea). Est., Coast. and Shelf Sci. 68(3-4): 489-498. dx.doi.org/10.1016/j.ecss.2006.02.018|
|In: Estuarine, Coastal and Shelf Science. Academic Press: New York. ISSN 0272-7714, more|
The stage of benthic re-colonization at a site formed by sand extraction was investigated some 10 years after the cessation of dredging. The examined post-dredging pit is one of five deep (up to 14 m) pits created with a static suction hopper on the sandy, flat and shallow (1-2 m) part of the inner Puck Bay (the southern Baltic Sea). The topography of the dredged area makes a specific trap for different kinds of organic matter. It is created by the small areas of post-dredging pits as compared to their depths. As a result, organic matter accumulation leads to anaerobic conditions and hydrogen sulfide formation. Macrofauna was not found to occur permanently in the deepest part (11 m) of the cup-shaped depression, which was characterized by its small area (0.2 km2) and steep walls. However, permanent occurrence of meiofauna (max. 180 ind. 10 cm-2, mainly Nematoda) was noted. Undoubtedly, re-colonization of benthic fauna assemblages, typical of shallow and sandy seabed of the Puck Bay, will not follow in a natural way in the area of post-dredging pits. Also, it could not be expected that the re-colonization sequence would result in the formation of a structure similar to that of the natural depression (the Kuznica Hollow).