A lower value of the Pu T 1/2ef in the Black Sea (4 years) indicates the higher
(respectively, more than 3 times) rate of self–purification of the Black Sea surface
water against Pu than in the Mediterranean Sea due to the more intense process of
sedimentation. This process contributes to the Pu accumulation in sediment and
should cause a difference in the plutonium redistribution in the seas ecosystems.
The field investigations of the specific activity of water and bottom sediment
regards to Pu in the Mediterranean (Papucci et al. 1996; Choppin and Pamela
1998) and the Black Sea (Baloga 1994; Strezov et al. 1996; IAEA 2004;
Tereshchenko and Polikarpov 2007; Tereshchenko et al. 2014, 2016) and evaluation, based on them, plutonium inventory in the water column and bottom sediment,
confirmed that the high rate of self–purification of the Black Sea water masses led
to a significant Pu redistribution difference between water and sediment in the
compared seas (Tereshchenko and Polikarpov 2007). Only about 11% of
239,240
Pu in
the Black Sea is concentrated in the water column and in the sediment – 89%,
whereas in the Mediterranean sea in open area the prevailing amount of plutonium
is in the water column – about 95% and in bottom sediment – only 5% (Papucci et al.
1996; Tereshchenko and Polikarpov 2007).
Therefore, in the Mediterranean Sea plutonium exhibits hydrotropic type of
biogeochemical behavior, as the prevailing part of it is concentrated in the water
masses (Papucci et al. 1996; WOMARS 2005). In the Black Sea plutonium concentrates in sediments and shows pedotropic type of biogeochemical behavior. As a
result, different types of biogeochemical behavior of plutonium in these seas and
high speed self–purification of surface waters in the Black Sea against plutonium it
becomes possible to change the direction of the resultant plutonium flow between
the seas.
16.3.4 The
239+240 Pu Flows Through the Bosphorus Strait
As it is known, the movement of water through the Bosphorus Strait comes from the
Black Sea by upper course and into the Black Sea – by lower course of the sea
water. According to data of different authors on the water exchange through the
Strait annual volumes of water passing through the Bosporus vary several times
(Ivanov and Belokopytov 2011). Therefore, average annual volumes of seawater
flowers were used by us in the calculations from the Black Sea by upper
Table 16.3 Characteristics of plutonium and cesium migration properties in the Black and
Mediterranean Sea, where: Т 1/2ef, – effective half–lives of radionuclide in surface water, C f –
concentration factor of radionuclide
Name of sea
Т 1/2ef, year (%)
C f of sediments
C f of suspended matter
239þ240
Pu
137
Cs
239þ240
Pu
137
Cs
239þ240
Pu
137
Cs
Mediterranean Sea 13 (100)
13 (100)
Black Sea
4 (31)
7 (54)
n  10
4
–10
5
n  10
2
n  10
4
–10
6
n  10
3
258
N.N. Tereshchenko
(respectively, more than 3 times) rate of self–purification of the Black Sea surface
water against Pu than in the Mediterranean Sea due to the more intense process of
sedimentation. This process contributes to the Pu accumulation in sediment and
should cause a difference in the plutonium redistribution in the seas ecosystems.
The field investigations of the specific activity of water and bottom sediment
regards to Pu in the Mediterranean (Papucci et al. 1996; Choppin and Pamela
1998) and the Black Sea (Baloga 1994; Strezov et al. 1996; IAEA 2004;
Tereshchenko and Polikarpov 2007; Tereshchenko et al. 2014, 2016) and evaluation, based on them, plutonium inventory in the water column and bottom sediment,
confirmed that the high rate of self–purification of the Black Sea water masses led
to a significant Pu redistribution difference between water and sediment in the
compared seas (Tereshchenko and Polikarpov 2007). Only about 11% of
239,240
Pu in
the Black Sea is concentrated in the water column and in the sediment – 89%,
whereas in the Mediterranean sea in open area the prevailing amount of plutonium
is in the water column – about 95% and in bottom sediment – only 5% (Papucci et al.
1996; Tereshchenko and Polikarpov 2007).
Therefore, in the Mediterranean Sea plutonium exhibits hydrotropic type of
biogeochemical behavior, as the prevailing part of it is concentrated in the water
masses (Papucci et al. 1996; WOMARS 2005). In the Black Sea plutonium concentrates in sediments and shows pedotropic type of biogeochemical behavior. As a
result, different types of biogeochemical behavior of plutonium in these seas and
high speed self–purification of surface waters in the Black Sea against plutonium it
becomes possible to change the direction of the resultant plutonium flow between
the seas.
16.3.4 The
239+240 Pu Flows Through the Bosphorus Strait
As it is known, the movement of water through the Bosphorus Strait comes from the
Black Sea by upper course and into the Black Sea – by lower course of the sea
water. According to data of different authors on the water exchange through the
Strait annual volumes of water passing through the Bosporus vary several times
(Ivanov and Belokopytov 2011). Therefore, average annual volumes of seawater
flowers were used by us in the calculations from the Black Sea by upper
Table 16.3 Characteristics of plutonium and cesium migration properties in the Black and
Mediterranean Sea, where: Т 1/2ef, – effective half–lives of radionuclide in surface water, C f –
concentration factor of radionuclide
Name of sea
Т 1/2ef, year (%)
C f of sediments
C f of suspended matter
239þ240
Pu
137
Cs
239þ240
Pu
137
Cs
239þ240
Pu
137
Cs
Mediterranean Sea 13 (100)
13 (100)
Black Sea
4 (31)
7 (54)
n  10
4
–10
5
n  10
2
n  10
4
–10
6
n  10
3
258
N.N. Tereshchenko