Distribution of Persistent Organic Pollutants and Mercury in Freshwater Ecosystems Under Changing Climate Conditions - Climate Change Impacts on Freshwater Ecosystems - page 187

Lake altitude

α -HCH γ -HCH HCB

4,4 -DDE

PCB 52

10

1.000 10 1000.0

100.0
10.0
1.0
0.1

10.00

R

R R

R

0.100 1 1

1.00

0.010 0.1

0.1

0.10

R

0.001

0.01

0.01 0.01

0 1000 2000 3000

0 1000 2000 3000 0

0 1000 2000 3000 1000 2000 3000 0 1000 2000 3000

PCB 101

PCB 118 PCB 153 PCB 138

PCB 180

10.0

100.0
10.0

10
1
0.1
0.01

100
10

10
1
0.1
0.01

R R R R R

1.0

1

1.0
0.1

0.1
0.01

0.1

0 1000 2000 3000

0 1000 2000 3000 0 1000 2000 3000 0 1000 2000 3000 0 1000 2000 3000

Altitude (m) Altitude (m) Altitude (m) Altitude (m) Altitude (m)

Annual average temperature

-HCH -HCH HCB

α γ

4,4 -DDE PCB 52

1.000

10
1

10
1

1000.0
100.0
10.0
1.0
0.1

10
1
0.1
0.01

R

0.100
0.010

0.1 0.1

R

R

R R

0.001

0.01 0.01

0.0035 0.0036 0.0037 0.0035 0.0036 0.0037 0.0035 0.0036 0.0037 0.0035 0.0036 0.0037

0.0035 0.0036 0.0037

PCB 101 PCB 118

PCB 153

PCB 138

10 PCB 180

10.0

100.00
10.00
1.00
0.10
0.01

100
10
1
0.1
0.01

10
1
0.1
0.01

R

1

1.0

0.1

R

R R R

0.1

0.01

0.0035 0.0036 0.0037

0.0035 0.0036 0.0037 0.0035 0.0036 0.0037 0.0035 0.0036 0.0037

0.0035 0.0036 0.0037

Temperature (K) Temperature (K) Temperature (K) Temperature (K) Temperature (K)

Figure 8.1 The concentrations of various OCs in fish (ng g −1 ) from high-mountain
European lakes depend on altitude and temperature (these two variables are roughly
related in the series). Each point is the mean for the fish analysed in each lake. As
observed, there is a correlation between the concentrations of high molecular weight
compounds (4,4´-DDE, and PCBs 118, 153, 138 and 180) and altitude or temperature.
This dependence, which implies greater contamination in the highest and most remote
zones, is not observed for the most volatile compounds. (Based on Vives et al . 2004a.)

region, where PBDEs were used earlier, the high-mountain distribution is
consistent with temperature dependence - which is also observed for PCBs
(Gallego et al . 2007). In contrast, for the Tatra region, where PBDEs were not
used until later, these contaminants have not yet reached a steady-state distribution
in the high mountains.
This trend becomes further marked upon joint comparison of the distributions
of PBDEs and PCBs in the two mountainous zones (Fig. 8.3). In the Pyrenean
lakes, parallel distributions of concentrations are observed, despite the difference
in time (more than 40 years) in the respective introduction of each type of
compound into the environment (Gallego et al . 2007). However, this correlation
is not observed in the Tatras.
Research on the food webs of these mountain lakes provides further clues on
the physico-chemical processes leading to the accumulation of these compounds
in organisms. The OC composition in water, chironomids, terrestrial insects,
cladocerans, molluscs, cyanobacteria and fish (brown trout) has been investigated