3 The Influence of Environmental Properties Variability
on Contaminants Distribution in Marine Arctic
Ecosystem
3.1 Temperature Raise
Increased temperature will have direct effect on contaminants cycling. The most
important direct effect may be more rapid degradation of organic contaminants
(Macdonald et al. 2005). Contaminant degradation processes are less efficient in the
Arctic due to low temperature and low solar radiation input. That is why most of
contaminants (POPs) persist in the Arctic for longer time than in warm and temperate regions (Bard 1999). More efficient degradation would be generally positive
process but is should be remembered that some degradation products may be more
toxic than their parent substances (Coats 1993). The good example is DDT that was
used as pesticide and it’s degradation product—DDE.
Positive consequence of increased temperature may be the alterations in species
energetics and trophic interactions. It was previously reported that adaptations to
the arctic climate imply an increased lipid production. Arctic marine organisms
have developed specific life cycles to match the productive period and the ability to
store energy in lipids (Falk-Petersen et al. 1987; Borga et al. 2002). Thus, the
transfer of energy between arctic trophic levels is more effective compared to
temperate regions. With the temperature rise the organisms will not produce so
much lipids and the change of energy transfer between trophic levels is expected
(Sobek et al. 2010). Since POPs accumulate in organisms in lipids, their transfer in
the trophic chain may be limited. Other advantage of temperature raise may be
dilution of organic pollutants in biological tissues due to growing body mass so
called “growth dilution” (Gobas 1993; Sobek et al. 2010).
3.2 Enhanced UV Radiation
Due to short periods of sun light presence arctic organisms have adapted to low
UV-light levels and show higher photosynthetic efficiencies at lower UV-light
levels and may grow even under ice cover. Organisms living in association with the
sea ice may be exposed to contaminants accumulated in sea ice, especially when it
melts (Pfirman et al. 1990; Weeks 1994). Thus, ice associated organisms may be
exposed to larger levels of contaminants during summer comparing to temperate
organisms.
With the ice cover decrease, the UV light and sunlight penetration into water
column will be larger. This will enhance the photodegradation of organic contaminants (Dąbrowska et al. 2004; Brillas 2014), and will help to eliminate a part of
POPs more vulnerable to degradation. It was also found that degradation of
Climate Change Influence on Migration of Contaminants …
83
on Contaminants Distribution in Marine Arctic
Ecosystem
3.1 Temperature Raise
Increased temperature will have direct effect on contaminants cycling. The most
important direct effect may be more rapid degradation of organic contaminants
(Macdonald et al. 2005). Contaminant degradation processes are less efficient in the
Arctic due to low temperature and low solar radiation input. That is why most of
contaminants (POPs) persist in the Arctic for longer time than in warm and temperate regions (Bard 1999). More efficient degradation would be generally positive
process but is should be remembered that some degradation products may be more
toxic than their parent substances (Coats 1993). The good example is DDT that was
used as pesticide and it’s degradation product—DDE.
Positive consequence of increased temperature may be the alterations in species
energetics and trophic interactions. It was previously reported that adaptations to
the arctic climate imply an increased lipid production. Arctic marine organisms
have developed specific life cycles to match the productive period and the ability to
store energy in lipids (Falk-Petersen et al. 1987; Borga et al. 2002). Thus, the
transfer of energy between arctic trophic levels is more effective compared to
temperate regions. With the temperature rise the organisms will not produce so
much lipids and the change of energy transfer between trophic levels is expected
(Sobek et al. 2010). Since POPs accumulate in organisms in lipids, their transfer in
the trophic chain may be limited. Other advantage of temperature raise may be
dilution of organic pollutants in biological tissues due to growing body mass so
called “growth dilution” (Gobas 1993; Sobek et al. 2010).
3.2 Enhanced UV Radiation
Due to short periods of sun light presence arctic organisms have adapted to low
UV-light levels and show higher photosynthetic efficiencies at lower UV-light
levels and may grow even under ice cover. Organisms living in association with the
sea ice may be exposed to contaminants accumulated in sea ice, especially when it
melts (Pfirman et al. 1990; Weeks 1994). Thus, ice associated organisms may be
exposed to larger levels of contaminants during summer comparing to temperate
organisms.
With the ice cover decrease, the UV light and sunlight penetration into water
column will be larger. This will enhance the photodegradation of organic contaminants (Dąbrowska et al. 2004; Brillas 2014), and will help to eliminate a part of
POPs more vulnerable to degradation. It was also found that degradation of
Climate Change Influence on Migration of Contaminants …
83