List of Figures 
298 
System Nordsee 
Fig. 4-38: Temporal evolution of herbicide concentrations at selected stations of the German 
Bight. 224 
Fig. 4-39: Median concentrations of coastal stations (S = 27.8 - 31.8) for 2004 - 2005 225 
Fig. 4-40: PFC concentrations (ng/L) in near-surface sea water (5 m) of the North Sea in August 
2007. 228 
Fig. 4-41: PFC concentrations relative to dry weight (top) and total organic carbon (bottom) in 
surface sediment of the German Bight in May 2004 229 
Fig. 4-42: PFOA and PFOS concentrations in a sediment core of the Skagerrak (57° 48'N, 8° 0' E) 
from August 2005 in comparison to CB153, pp'-DDD and HCB 230 
Fig. 4-43: Distribution statistics of the percent fraction of dissolved to total metal concentra 
tions in sea water as box and whisker plots. All boxstatistics are based on winter samples 
(JFM) from 1999 - 2005 and are separated in four figures by increasing salinity ranges (top 
left: 5 = 0 - 28, t. r.: 28 - 30, b. /.: 30 - 32, b. r.: 32 - 34) 239 
Fig. 4-44: Scatter plots of solved metal concentrations during January 2006 versus salinity. Only 
samples of salinity greater than 20 are included. Red line and equation: Linear regression 
(least squares); Black dashed line: Robust regression (weighted residuals) 241 
Fig. 4-45: Linear regression of solved metal concentration versus salinity for the period 2000 to 
2009. Distribution statistics of cruise-wise computed linear regression model parameters 
(intersect, slope, coefficient of determination R 2 ) in a box and whisker representation (me 
dian, 25 %, 75 % quantile, min, max, outliers). Each quarter of a year is represented by an 
individual box. Top row: red figures give the total number of included cruises, black figures 
the number of cruises with sufficient correlation of solved element concentration and sali 
nity (R 2 > 0.5). Intersect and slope figures aggregate only regression with R 2 > 0.5. ... 242 
Fig. 4-46: Seasonal cycle of solved element concentrations (Cd, Cu, Mn, Ni, Pb, Zn) in coastal 
surface water (salinity 30 - 32). Grey bar represents background reference concentration 
(BRC) 243 
Fig. 4-47: Spatial near surface (10 m) element concentration distributions in filtrated water in 
January 2006 245 
Fig. 4-48: Spatial near surface (10 m) element concentration distributions in filtrated water in 
January2007. 246 
Fig. 4-49: Spatial structure of solved element concentrations in near surface water during the 
summer survey 2006 247 
Fig. 4-50: Time series of yearly winter (JFM) distribution statistics in coastal (salinity 30-32) 
near surface (10 m) water as box and whisker plot. OSPAR background reference concent 
rations are displayed as grey bar. 249 
Fig. 4-51: Assessment of element burden in filtered near surface water (10m). Distribution sta 
tistics of measurements in coastal (salinity 30 - 32, upper row of figures) and open North 
Sea (salinity > 34, lower row of figures) water during the first quarter (JFM) of the years 
2006 and 2007 as box and whisker plot. The left hand colour code indicates the assess 
ment ranges. Blue: less than OSPAR-BRC; Green: greater than BRC and less than effect as 
sessment value; Red: greater than effect assessment value (cf. ch. 4.4.2.1, p. 235). The right 
hand colored dot relates to the assessment result of2007. An additional up-/downward 
arrow indicates a significant temporal trend during the recent five years 251 
Fig. 4-52: Sediment sampling sites German Bight (right), North Sea (left). 2006 sites are indica 
ted by an (o), 2007 sites by an (x). For any subsequent assessment of temporal trend and 
concentration level in sediment, the sites are combined to regional site groups, which are 
indicated by red circles 253