Geoscience Reference
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Aibulatov (2000) has pointed out that judging from the
137
Cs-distribution pat-
terns in the Kara Sea, it becomes evident that the Yenisey and Ob rivers (less
evident, however, in the latter case) should be considered as transport channels for
inputs of technogenic radionuclides to the Arctic Ocean waters. There are radio-
active sources in the ocean as well. The
137
Cs activity level reached its maximum in
1984 and was equal to 245 Bq/kg (in open sea); during the 1990s (1993) this level
was found to be equal to 100 Bq/kg (in the Yenisei estuary).
Arctic fjords have been classi
ed into categories of comparatively clean, con-
taminated, heavily contaminated, and potentially contaminated. Contaminated areas
include, for instance, Kola Gulf and, probably, all the fjords of the northern Kola
Peninsula west of Murmansk. The content of radionuclides in phytobenthos, in the
coastal zone east of Murmansk, is low. Evidently, there has not been recently any
serious radionuclide penetration into this area. A rather low gamma-nuclide level
(1
3 Bq/kg) is typical for the zoobenthos of the Barents Sea. This is also true for the
Kara Sea.
An impact of all the sources of radioactivity in the zone of the Arctic coast on the
local population has not been assessed reliably enough. It was particularly dif
-
cult
to separately identify natural and anthropogenic components of such an impact.
Aibulatov (2000) has discussed future research of the Russian Arctic radioactive
pollution, including:
Development of a coordinated program Russian Arctic Sea Radioactivity Eco-
logical Monitoring.
Assessments of impacts of different radioactive sources on the contamination of
the Arctic marine environment including water basins, land, and atmosphere.
Studies of detailed space and time variability of various long-lived technogenic
radionuclides in bottom sediments.
A detailed examination of all Novaya Zemlya fjords in connection with
dumping radioactive waste.
Research of the impact of radioactive pollution on the Arctic marine ecosystem
dynamics.
Studying medical aspects of environmental pollution in the Arctic.
The fundamental study of radioactivity of the Arctic and sub-Arctic marine
ecosystems have been undertaken by Matishov and Matishov (2001), which resulted
in the substantiation of a new branch of science
radiational ecological oceanology.
Investigations have been conducted of the level of arti
—
cial radionuclide concen-
tration in both environment and biota of the bays and inlets (the Kola, the Chernaya,
the West Litsa), where radioactively dangerous objects are located. In this context, a
classi
cation has been suggested for coastal areas (bays, gulfs, fjords) in accordance
with contamination levels for bottom sediments. The discovery of a bio
filter of
pelagic and coastal zone during the processes of self-puri
cation of water reservoirs
and transport of radionuclides from water to bottom sediments, is of great impor-
tance. For the
first time the levels of
137
Cs,
90
Sr,
239,240
Pu concentrations for different
types and populations of sea organisms were measured. Migrations of radioisotopes
along the trophic chains (from macrophytes and plankton to zoobenthos,
fish, birds,
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