The Arctic Environmental Problems - New Ecoinformatics Tools in Environmental Science: Applications and Decision-making - page 535

(solid curve 1) and the data of curves 2 and 3 (Terziev 1992) is explained by the
assumption that the trophic structures of the different Arctic Seas are described by
means of the general scheme represented in Fig. 6.3 and the discrimination between
the ecological elements in each of the Arctic Seas is not taken into consideration in
the SSMAE.
Figure 6.10 indicates that the vegetative period for the phytoplankton in the
Barents Sea equals 4.9 months as shown by the effects on the ecosystem contri-
bution to the self-clearing of the oil hydrocarbons (dashed curve.) In the case
considered, the Barents Sea ecosystem neutralizes about 25 % of oil hydrocarbons
during the vegetative period. The rest of the time, this value oscillates near 3 %. The
dispersion of these estimates with latitude reaches 53 %. For example, in the
northern part of the Barents Sea the vegetative period varies from 2.6 to 3.1 months,
while in the southern latitudes the variation is 5.3

5.8 months. Consequently, the
ecosystem role in the sea cleaning of the oil hydrocarbons is 8 and 36 % for the
northern and southern water areas, respectively. Such estimates can be calculated
for each cell

-

ʔφ × ʔʻ × ʔ z of the Arctic Basin.

6.4.6.5 The Dynamics of Pollutants in the Arctic Basin

An important problem is that of determining and understanding the role of the
various pollutant sources in forming the pollution levels for the different Arctic
Basin areas: McCauley and Meier (1991). One major function of the SSMAE is to
estimate the pollution dynamics in each of the cells Ω ij ↆ Ω as a function of time.

The in uence of the pollutant sources on the Arctic ecosystem occurs through the

boundary area

fl

X R [ X P [ X B [ X N [ X C and through the atmosphere. The total
picture of the spatial distribution of pollutants is formed from the local dynamic
processes. The incompleteness of the Arctic database leads to the need for
assumption to be made for some scenarios in the framework: Krapivin et al. (1998a)
estimated the flow of pollutants to the Kara Sea based on the experimental mea-

surements of radionuclear pollution and heavy metals in the Angara-Yenisey river
system. Therefore, the SSMAE is used to estimate the

fl

fl flow of pollutants from the

Kara Sea to the other water areas of the Arctic Basin.
The Ob and Yenisey rivers are considered to be the main sources of radio
nuclear pollution, heavy metals and oil hydrocarbons for the Kara Sea (Table 6.10 ).
Figure 6.9 shows the in

flow on the volume of pollutants
transported by the Kara Sea aquageosystem to the Central Basin. As shown by
curves 1 and 2, the transference of heavy metals and radionuclides from the Ob and
Yenisey rivers through the Kara Sea aquageosystem to the Central water areas of
the Arctic Basin amounts to 2.1 % when the river

fl uence of the river fl

flow varies from 500 to
1,000 km 3 /year and after that it begins to grow linearly up to 7.6 % for 2,000 km 3 /
year. Hence, there is a critical level of pollution for the Kara Sea ecosystem beyond
which it does not have time to dilute the

fl

flow of heavy metals and radio nuclear
pollutants. Similar estimations can be obtained for the other elements of set

fl

Ω R,

using the rivers referred to in Table 6.8 .