the contrary, served as a biogeochemical barrier on the way of the Chernobyl
plutonium migration from the Black Sea catchment area into the Mediterranean
Sea basin. So, it appears the plutonium pedotropic type of biogeochemical behavior
in the Black Sea ecosystem and the high rate of self–purification of surface waters
against
239þ240 Pu in the Black Sea on the plutonium flows and their direction
between the seas.
16.3.5 Alhpa-Radioisotopes of Plutonium in the Black Sea
Bottom Sediments
The study of the spatial distribution of
239þ240 Pu in the Black Sea sediments showed
that, as the distribution in water, it was of patchy (Fig. 16.4) (Strezov et al. 1996;
IAEA 2004; Tereshchenko et al. 2013; Tereshchenko et al. 2014, 2016). On the one
hand, this is due to the composition of bottom sediment, and on the other hand –
with a history of the
239þ240 Pu input and, in particular, proximity to the Dnieper–
Bug estuary, as well as to the Danube and North Crimean channel mouth, and hence
with the levels of concentration activity of water in relation to
239þ240 Pu and with
the rate of the sedimentation fluxes of particulate matter (Tereshchenko et al. 2013,
2016).
16.3.6 Sedimentation
239þ240
Pu Fluxes into Bottom
Sediment
Application of radiotracer technologies using man–made radioactive isotopes,
input into the Black Sea ecosystem due to nuclear events (Gulin et al. 2002,
2012; Polikarpov et al. 2008), allowed values of sedimentation rate (SR), the
particulate matter accumulation rate (MAR) and the
239þ240 Pu sedimentation
fluxes. The obtained results showed that the plutonium fluxes depends on both the
239þ240
Pu concentration activity in the water and on the rate of sedimentation
processes, trophic level of seawater area and the distance from sources of terrigenous suspended matter. In general, in the areas of open sea SR was 0.4–0.9, on the
continental slope – about 2.2, in nearshore areas – from 2.4 to 11.5 mm/year. The
highest values of SR confined to the estuarine areas of the Danube, the Dnieper and
the Bug (Gulin et al. 2002; Polikarpov et al. 2008).
Decrease of the
239þ240 Pu in water with time (Fig. 16.2 and 16.3) led to lower
plutonium sediments fluxes in bottom sediment and falling asleep sediment with
high content of
239þ240 Pu the cleaner bottom sediment. This is confirmed by data on
the vertical distribution of the
239þ240
Pu concentration activity of sediment
(Fig. 16.5) (Tereshchenko et al. 2016).
Method of geochronological dating of sediment made it possible to determine
the depth of the maximum of the Chernobyl and global fallout and calculate the
260
N.N. Tereshchenko
plutonium migration from the Black Sea catchment area into the Mediterranean
Sea basin. So, it appears the plutonium pedotropic type of biogeochemical behavior
in the Black Sea ecosystem and the high rate of self–purification of surface waters
against
239þ240 Pu in the Black Sea on the plutonium flows and their direction
between the seas.
16.3.5 Alhpa-Radioisotopes of Plutonium in the Black Sea
Bottom Sediments
The study of the spatial distribution of
239þ240 Pu in the Black Sea sediments showed
that, as the distribution in water, it was of patchy (Fig. 16.4) (Strezov et al. 1996;
IAEA 2004; Tereshchenko et al. 2013; Tereshchenko et al. 2014, 2016). On the one
hand, this is due to the composition of bottom sediment, and on the other hand –
with a history of the
239þ240 Pu input and, in particular, proximity to the Dnieper–
Bug estuary, as well as to the Danube and North Crimean channel mouth, and hence
with the levels of concentration activity of water in relation to
239þ240 Pu and with
the rate of the sedimentation fluxes of particulate matter (Tereshchenko et al. 2013,
2016).
16.3.6 Sedimentation
239þ240
Pu Fluxes into Bottom
Sediment
Application of radiotracer technologies using man–made radioactive isotopes,
input into the Black Sea ecosystem due to nuclear events (Gulin et al. 2002,
2012; Polikarpov et al. 2008), allowed values of sedimentation rate (SR), the
particulate matter accumulation rate (MAR) and the
239þ240 Pu sedimentation
fluxes. The obtained results showed that the plutonium fluxes depends on both the
239þ240
Pu concentration activity in the water and on the rate of sedimentation
processes, trophic level of seawater area and the distance from sources of terrigenous suspended matter. In general, in the areas of open sea SR was 0.4–0.9, on the
continental slope – about 2.2, in nearshore areas – from 2.4 to 11.5 mm/year. The
highest values of SR confined to the estuarine areas of the Danube, the Dnieper and
the Bug (Gulin et al. 2002; Polikarpov et al. 2008).
Decrease of the
239þ240 Pu in water with time (Fig. 16.2 and 16.3) led to lower
plutonium sediments fluxes in bottom sediment and falling asleep sediment with
high content of
239þ240 Pu the cleaner bottom sediment. This is confirmed by data on
the vertical distribution of the
239þ240
Pu concentration activity of sediment
(Fig. 16.5) (Tereshchenko et al. 2016).
Method of geochronological dating of sediment made it possible to determine
the depth of the maximum of the Chernobyl and global fallout and calculate the
260
N.N. Tereshchenko