Fróðskaparrit - 01.01.2009, Page 176

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CHEMICAL SEDIMENT VARIABLES FROM THE FAROE AREA:
ORCANIC CONTENT, NITROCEN, PHOSPHORUS, ZINC, AND COPPER
(2004).
The normal range of organic content, ni-
trogen, phosphorus, zinc and copper in
the surface layers of seabed sediments in
the Faroe area
Organic content (LOI)
The data collected by Kaldbak Marine Bio-
logical Laboratory showed a wide variance of
organic content in the sediment. The overall
lowest value found was 0.5 % and the highest
was 13.0 % (Table 1 and 2).
Bloch etal. (1986) found values between
2.4 % and 10.5 %. Gaard (1990) gave infor-
mation on organic content from two loca-
tions (SK05 and SK07) and found values be-
tween 6.2 % and 13.8 %. Hoydal and Dam
(2004) analyzed sediment samples from 13
locations and found values between 3.3 %
and 13.3 %, and Johansen (2006), who sam-
pled at eight different locations, found mean
LOI values from 2.4 % to 13.0 %.
Therefore, the overall variability of or-
ganic matter in seabed sediments from
Faroese inshore waters is between 0.5 % and
13.8%.
Josefson (2001) found LOI values be-
tween 2.7 and 4.3 % at depths from 317-
367 m.
Grøsvik et al. (2000) found LOI values
from 2.4 to 4.2 % with a mean of 3.3 % in
samples from depths between 275 and
580 m.
Mannvik and Petersen (2002) found LOI
values in the range 1.3-2.9 % with a mean
value of 2.0 %. They sampled in the Faroe-
Shetland Channel at depths between 820-
1148 m.
Kaldbak Marine Biological Laboratory
(2006) sampled just off the Faroe shelf at
depths around 470 m and found LOI values
in the range 1.9-5.6 % with a mean value of
2.7 %.
From these four reports from deeper
waters, it can be concluded that values for
organic content in the offshore sediments
were from 1.3-5.6 % and means were 3.3 %,
2.0 % and 2.7 %, respectively.
Nitrogen
Very few data on total nitrogen in marine
sediments from the Faroe Islands are avail-
able. Besides the data collected by KMBL (91
samples), there are only two reports with
further information. Hoydal and Dam (2004)
analyzed 15 samples from soft sediments in