Atlantic including an area of the Middle Atlantic Ridge, of the Biscay, of the Iberian Sea,
of the upwelling zone off NW-Africa, of the Laguna de Terminos, Gulf of Mexico, and of
the Antarctic Sea.
In table 1, some of these areas are quoted as illustrations of the amount of actinomycetes
in relation to the total viable bacterial counts. Apart from the Antarctic Sea actinomycetes could be proved in the sediments of the majority of the stations of all areas. But in the
open sea viable counts of the actinomycetes are usually low ranging about 100 cfu per ml
wet sediment. They are indicated per thousand of the total viable counts. The mangroves
exhibited the highest density of actinomycetes amongst the areas investigated also within
their high salinity regions. In the sediments off NW-Africa the absolute numbers of
actinomycetes per ml sediment are comparatively low in spite of the fact that this area is
situated in a dust zone coming from the Sahara. Up till now actinomycetes could not be
detected in the sediments of the Antarctic Sea. This may be due on the one hand to the
absence of soil covered land and on the other hand to the Antarctic Ring Ocean which is
seperated from the neighboured oceans.
depth
m
sampling sites
total
Act pos.
cfu/ml s
(mean
Bacteria
ediment
values)
Act.
Act. V %
Norwegian Sea
0-200
16
14
918000
169
0.18
200-1000
41
40
394 000
298
0.8
1000-2000
14
14
106 000
164
1.54
> 2000
16
16
4 600
63
13.69
Antartic Sea
0-200
2
0
18 743 000
0
0.0
200-1000
7
0
347 000
0
0.0
1000-2000
4
0
279000
0
0.0
> 2000
12
0
162000
0
0.0
North Sea
0-200
38
34
1637 000
480
0.29
200-1000
5
4
665 000
790
11.88
1000-2000
5
4
665000
790
11.88
>2000
5
4
665 000
790
11.88
Off NW-Africa
0-200
10
6
246000
46
0.19
200-1000
8
8
203 000
85
0.41
1000-2000
7
7
13 800
85
6.16
> 20008
8
8
4 800
46
9.58
Mangrove, Mexico
0-10
10
10
10
16651000
397 000
Table 1 : Viable counts of bacteria and actinomycetes in the bottom sediments of different depth ranges.
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