Fróðskaparrit - 01.01.2009, Page 175

EVNAFRØÐILIGAR BLEYTBOTNSDÁTUR Á FØROYSKUM HAVØKI:
LÍVRUNNIÐ TILFAR, NITROGEN, FOSFOR, SINK OG KOPAR
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SK07 these were respectively 9.7 % and 12.6
%. The LOI mean value for all samples was
10.0 % for SK05 and 10.9 % for SK07.
From the data in Table 12 it is not possi-
ble to recognize any pattern of change. The
LOI values of SK05 were highly variable, while
LOI values at SK07 seem to be more con-
stant. There is no obvious reason for the vari-
ability of the LOI values at SK05, but patchi-
ness and imprecise positioning could explain
the differences. It is, however, difhcult to ex-
plain why SK07 has more constant LOI val-
ues compared to SK05.
In Table 13, data from four sites at dif-
ferent localities are shown. These are data
from sieved samples (0.5 mm). One of the lo-
calities (Gøtuvík) has been sampled for nine
consecutive years, the others for four to five
years. All four localities show variable values
of organic content in the sediment. Miðvág-
ur seems to be less variable than the other
localities and a possible explanation could be
that this is an exposed site with sandy sedi-
ments. Gøtuvík, which has been sampled for
nine consecutive years, varied between 3.2
and 9.5 %.
The data in Table 13 are from sieved
samples and are, therefore, not directly com-
parable to SK05 and SK07 in Table 12.
Station Depth m Sediment LOI g/Lg Zinc mg/kg Copper mg/kg
1 TT00 Fine Sand 1.5 18.5 7.8
2 1148 Medium sand 1.5 21.7 6.1
3 1090 Fine Sand 1.3 13.4 5.3
6 1180 Coarse sand 1.5 21.5 9.3
8 820 Fine Sand 2.9 20.5 10.8
9 930 Fine Sand 2.2 17.3 9.3
T T 970 Fine Sand 1.7 13.9 7.1
T2 990 Medium sand 1.6 13.6 5.7
T3 1020 Fine Sand 2.0 16.1 8.2
14 990 Fine Sand 1.7 13.9 6.3
TS 1050 Fine Sand 2.6 9.1 21.8
T6 1050 Fine Sand 1.9 16.0 7.8
T7 1060 Fine Sand 2.2 17.2 8.0
18 1080 Fine Sand 2.0 15.0 7.3
19 1070 Fine Sand 2.7 16.3 8.5
20 1100 Fine Sand 2.9 17.2 8.9
Min 1.3 13.4 5.3
Max 2.9 21.8 10.8
Mean 2.0 17.1 7.8
Std. dev. 0.5 2.9 1.5
Table 10. Values of LOI, copperand zincfrom the deep slope of the Faroe Shetland channel. Data from Mannvik
and Petersen (2002).