Fróðskaparrit - 01.01.2009, Side 173

EVNAFRØÐILIGAR BLEYTBOTNSDÁTUR Á FØROYSKUM HAVØKI:
LÍVRUNNIÐ TILFAR, NITROGEN, FOSFOR, SINK OG KOPAR
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Station Depth m Sediment LOI % Z inc fng/tø C opper mg/kg
l.a 453 Fine Sand 4.0 28.6 13.1
1.b 458 Fine Sand 3.5 29.8 13.7
l.c 464 Coarse sand 2.6 33.8 18.9
l.d 486 Fine Sand 3.3 19.4 7.6
2 459 Medium sand 3.3 35.8 17.8
4 440 Coarse sand 2.7 36.7 16.7
5 461 Fine Sand 3.8 24.3 10.5
6 580 Coarse sand 2.7 42.7 27.0
7 470 Fine Sand 3.3 38.5 17.1
8 487 Fine Sand 3.4 28.6 12.7
9 .a 463 Fine Sand 4.2 33.0 15.7
9.b 480 Fine Sand 4.0 30.1 13.6
9.c 469 Fine Sand 4.1 30.0 13.2
9.d 341 Medium sand 2.9 35.1 28.7
lO.a 517 Medium sand 3.1 23.6 17.3
lO.b 424 Medium sand 3.3 22.1 16.3
10.C 389 Medium sand 3.1 24.8 20.8
lO.d 354 Medium sand 3.3 20.8 17.1
lO.e 275 Medium sand 2.5 11.2 9.1
lO.f 494 Medium sand 2.4 15.9 12.0
Min 2.4 11.2 7.6
Max 4.2 42.7 28.7
Mean 3.3 28.2 15.9
Std. dev. 0.5 8.0 5.3
Table 9. Sediment values of LOI, copper and zinc from south of the Faroe Islands on the northem slope of the
Faroe Shetland Channel. Data from Grøsvik et al. (2000).
analyzed for LOI, copper and zinc. Samples
were taken from the top 2 cm of undis-
turbed seabed sediment and samples were
obtained by 0.1 m2 van-Veen-type grab.
Samples were analyzed at ALcontrol Labora-
tories, Sweden. Positioning accuracy of the
sample sites was within ± 5 meters.
The stations are all within a distance of
1250 m and vary between 460-489 m in
depth (Table 11). The sediments were de-
scribed as gravelly sands to silt/clay sands.
Comparability ofdata.
When comparing data from different
sources it is important to consider the com-
parability. Differences could be found in the
way samples were taken, in treatment after
sampling or prior to analysis, and in the
method of analysis. The most important sin-
gle source factor of error is without a doubt
the uncertainty of precise localization of a
sample site when comparing samples from
the same site. This may particularly be the
case for the oldest samples, when the accu-
racy of positioning systems was less precise.
Approximately all samples in Table 1 and
2 were sieved (0.5 mm) before analysis. There
is no doubt that in some cases this has an ef-