34
3 Study Area
to 80 flm in winter and approx. 60 flm in summer (Krogel 1997». This leads to a
higher particle load in the water column during these months. This results in a
significant decrease in abundance of the finer fractions (in particular the <63 flm
fraction) in the sediments during winter.
The sediment distribution in the central part of the Swinnplate clearly reflects
the seasonal alternation between a winter situation dominated by hydrodynamical
sorting and a summer situation influenced by biodeposition (Bartholoma, Flemming unpub!. data). In the winter, the mud content of the sediments decreases to
less than 10 %. The mud is resuspended and exported in suspension. However, the
seasonal sediment distribution and/or -zonation remains largely unchanged over
longer time intervals.
With regard to the repeated observation of this seasonal alternation, the increased heterogeneity after the strong ice winter of 1995/96 had only a short term
effect. The loss of the mussel beds lead to deeper incisions in the topography.
After removal of the top sediment layer, the underlying sediments were easily
exported. As there was no biodeposition, the effect of the ice winter was even
more pronounced on the mud-poor Groninger Plate (Bartholoma, Flemming unpub!. data). Without biogenic sedimentation, the decrease in mud on the Groninger
Plate during the ice winter will have longer lasting effects than on the Swinnplate
(Chap. 3.6.1).
Acknowledgements
This chapter is based on the results and data of A. Bartholoma, B.W. Flemming
and their colleagues hom the Senckenberg Institute. Their work was published as
cited in the text and further unpublished data were kindly provided. A reviewer
gave helpful comments on the manuscript. The project was funded by the German
Bundesministerium fur Bildung, Wissenschaft, Forschung und Technologie
(BMBF) under grant number 03FO 112 A and B. The responsibility for the contents
of the publication rests with the author.
References
Bartholoma A (1993) Zeitliche Variabilitat und raumliche Inhomogenitat in den Substrateigenschaften und der Zoobenthosbesiedlung im Umfeld von Miesmuschelbanken. D. Hydrodynamik. Senckenberg am Meer Bericht 93/ I: 117-123
Bartholoma A, Flemming BW (1993) Zeitliche und raumliche Variabilittit in den Sedimentparametern und der Morphologie auf der Groninger Plate (Spiekerooger Watt). Senekenberg
am Meer Berieht 93/ I: 5-48
Ehlers J (1988) The morphodynamies of the Wadden Sea. Balkema, Rotterdam
Eitner V (1996) Morphological and sedimentological development of a tidal inlet and its catchment area (Otzumer BalJe, southern North Sea). J Coast Res 12: 271-293
Fach B (1996) Die Entwicklung del' Windverhaitnisse in der Deutschen Bueht seit 1965, als
wiehtiger Umwelteintlu13 auf die Kiistenzone. Diplomarheit, Fachhochschule Wilhelms haven
Fitzgerald OM, Penland S, Nummedal 0 (1984) Changes in tidal inlet geometry due to backbarriel' filling: East Frisian Islands, West Germany. Shore & Beach 52: 3-8
Flemming BW (1990) Zur holoz~inen Entwicklung, Morphodynamik und faziellen Gliederung
del' mesotidalen Diineninsel Spiekeroog (Siidliche Nordsee). In: Willems H, Wefer G, Rinski
3 Study Area
to 80 flm in winter and approx. 60 flm in summer (Krogel 1997». This leads to a
higher particle load in the water column during these months. This results in a
significant decrease in abundance of the finer fractions (in particular the <63 flm
fraction) in the sediments during winter.
The sediment distribution in the central part of the Swinnplate clearly reflects
the seasonal alternation between a winter situation dominated by hydrodynamical
sorting and a summer situation influenced by biodeposition (Bartholoma, Flemming unpub!. data). In the winter, the mud content of the sediments decreases to
less than 10 %. The mud is resuspended and exported in suspension. However, the
seasonal sediment distribution and/or -zonation remains largely unchanged over
longer time intervals.
With regard to the repeated observation of this seasonal alternation, the increased heterogeneity after the strong ice winter of 1995/96 had only a short term
effect. The loss of the mussel beds lead to deeper incisions in the topography.
After removal of the top sediment layer, the underlying sediments were easily
exported. As there was no biodeposition, the effect of the ice winter was even
more pronounced on the mud-poor Groninger Plate (Bartholoma, Flemming unpub!. data). Without biogenic sedimentation, the decrease in mud on the Groninger
Plate during the ice winter will have longer lasting effects than on the Swinnplate
(Chap. 3.6.1).
Acknowledgements
This chapter is based on the results and data of A. Bartholoma, B.W. Flemming
and their colleagues hom the Senckenberg Institute. Their work was published as
cited in the text and further unpublished data were kindly provided. A reviewer
gave helpful comments on the manuscript. The project was funded by the German
Bundesministerium fur Bildung, Wissenschaft, Forschung und Technologie
(BMBF) under grant number 03FO 112 A and B. The responsibility for the contents
of the publication rests with the author.
References
Bartholoma A (1993) Zeitliche Variabilitat und raumliche Inhomogenitat in den Substrateigenschaften und der Zoobenthosbesiedlung im Umfeld von Miesmuschelbanken. D. Hydrodynamik. Senckenberg am Meer Bericht 93/ I: 117-123
Bartholoma A, Flemming BW (1993) Zeitliche und raumliche Variabilittit in den Sedimentparametern und der Morphologie auf der Groninger Plate (Spiekerooger Watt). Senekenberg
am Meer Berieht 93/ I: 5-48
Ehlers J (1988) The morphodynamies of the Wadden Sea. Balkema, Rotterdam
Eitner V (1996) Morphological and sedimentological development of a tidal inlet and its catchment area (Otzumer BalJe, southern North Sea). J Coast Res 12: 271-293
Fach B (1996) Die Entwicklung del' Windverhaitnisse in der Deutschen Bueht seit 1965, als
wiehtiger Umwelteintlu13 auf die Kiistenzone. Diplomarheit, Fachhochschule Wilhelms haven
Fitzgerald OM, Penland S, Nummedal 0 (1984) Changes in tidal inlet geometry due to backbarriel' filling: East Frisian Islands, West Germany. Shore & Beach 52: 3-8
Flemming BW (1990) Zur holoz~inen Entwicklung, Morphodynamik und faziellen Gliederung
del' mesotidalen Diineninsel Spiekeroog (Siidliche Nordsee). In: Willems H, Wefer G, Rinski