300 
List of Figures 
Figure 4-11: pH in bottom sea water of the German Bight in February 2008, January 
2009, 2010 and 2011 164 
Figure 4-12: Geographical distributions (pmol/L) of DIN and total-nitrogen in bottom sea 
water of the German Bight in February 2008 to January 2011 165 
Figure 4-13: Geographical distributions (pmol/L) of DIP (dissolved anorganic phosphate) 
and total-phosphorus in bottom sea water of the German Bight in February 2008 to 
January 2011 167 
Figure 4-14: Geographical distributions (pmol/L) of silicate in bottom sea water of the 
German Bight in February 2008 to January 2011 168 
Figure 4-15: Redfield ratio (pmol/pmol) in the bottom water of the German Bight in Fe 
bruary 2008 to January 2011 169 
Figure 4-16: DIN concentration (pmol/L) in bottom water of the North Sea in summer 
2008 and 2010 170 
Figure 4-17: Phosphate concentration (pmol/L) in bottom water of the North Sea in sum 
mer 2008 and 2010 170 
Figure 4-18: Silicate concentration (pmol/L) in near-bottom water of the North Sea in 
summer 2008 and 2010 171 
Figure 4-19: High-resolution time series of nutrients at the BSH network station UFS 
German Bight in 2011 173 
Figure 4-20: Time series of wintry DIN and TN concentrations. Prediction limits are de 
picted as 95 % bars 176 
Figure 4-21: Time series of wintry DIP and TP concentrations. Prediction limits are de 
picted as 95 % bars. Reference concentrations from 1936 177 
Figure 4-22: Time series of wintry silicate concentrations. Prediction limits are depicted 
as 95 % bars. Reference concentrations from 1936 178 
Figure 4-23: Seasonal pH-data in the German Bight from January 1990 to August 
2011 180 
Figure 4-24: Mean pH-concentrations from 1990 to 2011 in seawater of the German 
Bight. The black dotted line shows the declining trend. 181 
Figure 4-25: Oxygen saturation (%) in near-bottom water of the North Sea in summer 
2008 and 2009 182 
Figure 4-26: Oxygen saturation (%) in near-bottom water of the North Sea in summer 
2010 and 2011 182 
Figure 4-27: Annual chlorophyll-a concentration at the station HELGO from 2008-2011; 
satellite data evaluation (green) in comparison to in situ data (red) 184 
Figure 4-28: Chlorophyll-a concentration in sea-surface water of the North Sea in sum 
mer 2008 and 2009 185 
Figure 4-29: Chlorophyll-a concentration in sea-surface water of the North Sea in sum 
mer 2010 and 2011 186 
Figure 4-30: Geographical distribution of TOC contents of surface sediments in the Ger 
man Bight (mean values of May 2008 and May 2011) 188 
Figure 4-31: Concentration of chlorinated hydrocarbons (CKW) in the river Elbe at Stade 
and Cuxhaven from 2008 to 2011; (Box plot: the box represents the middle 50 % of 
the data; the horizontal line shows the median; the vertical lines represent the 1.5 
interquartil ranges of the lower and upper quartils) 190 
Figure: 4-32: Concentrations of HCH isomers in the German Bight from 2008-2011. . . 191