14
11
10
8
6
4
•
• A
o----~ B
-0 ____ _ --0 _____ _
70
60
50
40
30
10
10
0~--r__r_,r_--_,----~--------r_------------,_------------_r~~0
300
500
700
1000
1500
~1000 m
Fig. 4. In the composition of the bottom fauna the effects of sewage disposal are reflected. Until
Apri11972, the city of Kiel, Germany, discharged 50,000 m 3 of untreated sewage daily into the
Kiel Bight, containing 18 t particulate organic matter, 2.4 t phosphorus and 1.4 t nitrogen. The
outlet was located 200 m from the beach at a water depth of 2.5 m. About 15 animal species
comprise the bottom fauna in the outlet region. At a distance of 200-700 m away from the outlet sensitive sand-inhabiting species like the amphipod Bathyporeia disappear; less demanding
forms such as the polychaete Pygospio get the upper hand. Still closer to the outlet the sediment
is well enriched with organic matter. Oligochaets and the polychaet Capitella dominate at a distance of 50 -1 00 m from the outlet. In this transect the number of species hardly varies, but the
biomass of the bottom fauna near the outlet is 15, and the number of individuals 50 times higher
than further distant. Therefore the calculation of diversity results in lower values. The graph
represents a transect north of the outlet, at a water depth of 3 m. Indicated are biomass (B in g/m 2
wet weight without molluscs and echinoderms) and abundance (A in 1000 individuals/m 2 ) (Anger
1975)
Table 4. Pollution stress on the Lower Weser River, Germany, by domestic effluents and organic
industrial effluents in 1978. Treatment plants are under construction or being planned so that the
strain will be alleviated in the coming years. (Data according to Wasserwirtschaftsamt Bremen and
Brake, and Wasserbehbrde Bremerhaven)
km below
Bremen Weir
8.5
11.0
11.2
16-23
21.5
25.2
32.5
40-42
42.5
48.1
59.1
57-66
65-67
Contributors
Waste treatment plant (mechanical) Bremen-Seehausen
(construction of biological plant started 1980)
City of Delmenhorst and wool spinning-mill (treatment plant to
be ready in 1979)
Klbckner Steel Factory
Various villages and industry
Bremen Wool Factory
Waste water trreatment plant Bremen-Farge
Waste water treatment plant Elsf1eth and industry
Waste water treatment plants Brake
Fat refinery Brake (treatment plant to be ready in 1980)
Treatment plant Rodenkirchen
Treatment plant Nordenham
Various industry of Nordenham
City of Bremerhaven including fish industry and harbors (treatment
plant to be ready in 1982)
Total (corresponding to about 1.4 million Population Equivalent Units)
10
33,000
10,000
6,000
100
3,500
300
90
820
2,000
150
110
1,000
21,300
78,000
11
10
8
6
4
•
• A
o----~ B
-0 ____ _ --0 _____ _
70
60
50
40
30
10
10
0~--r__r_,r_--_,----~--------r_------------,_------------_r~~0
300
500
700
1000
1500
~1000 m
Fig. 4. In the composition of the bottom fauna the effects of sewage disposal are reflected. Until
Apri11972, the city of Kiel, Germany, discharged 50,000 m 3 of untreated sewage daily into the
Kiel Bight, containing 18 t particulate organic matter, 2.4 t phosphorus and 1.4 t nitrogen. The
outlet was located 200 m from the beach at a water depth of 2.5 m. About 15 animal species
comprise the bottom fauna in the outlet region. At a distance of 200-700 m away from the outlet sensitive sand-inhabiting species like the amphipod Bathyporeia disappear; less demanding
forms such as the polychaete Pygospio get the upper hand. Still closer to the outlet the sediment
is well enriched with organic matter. Oligochaets and the polychaet Capitella dominate at a distance of 50 -1 00 m from the outlet. In this transect the number of species hardly varies, but the
biomass of the bottom fauna near the outlet is 15, and the number of individuals 50 times higher
than further distant. Therefore the calculation of diversity results in lower values. The graph
represents a transect north of the outlet, at a water depth of 3 m. Indicated are biomass (B in g/m 2
wet weight without molluscs and echinoderms) and abundance (A in 1000 individuals/m 2 ) (Anger
1975)
Table 4. Pollution stress on the Lower Weser River, Germany, by domestic effluents and organic
industrial effluents in 1978. Treatment plants are under construction or being planned so that the
strain will be alleviated in the coming years. (Data according to Wasserwirtschaftsamt Bremen and
Brake, and Wasserbehbrde Bremerhaven)
km below
Bremen Weir
8.5
11.0
11.2
16-23
21.5
25.2
32.5
40-42
42.5
48.1
59.1
57-66
65-67
Contributors
Waste treatment plant (mechanical) Bremen-Seehausen
(construction of biological plant started 1980)
City of Delmenhorst and wool spinning-mill (treatment plant to
be ready in 1979)
Klbckner Steel Factory
Various villages and industry
Bremen Wool Factory
Waste water trreatment plant Bremen-Farge
Waste water treatment plant Elsf1eth and industry
Waste water treatment plants Brake
Fat refinery Brake (treatment plant to be ready in 1980)
Treatment plant Rodenkirchen
Treatment plant Nordenham
Various industry of Nordenham
City of Bremerhaven including fish industry and harbors (treatment
plant to be ready in 1982)
Total (corresponding to about 1.4 million Population Equivalent Units)
10
33,000
10,000
6,000
100
3,500
300
90
820
2,000
150
110
1,000
21,300
78,000