Environmental Engineering Reference
In-Depth Information
Figure 2.
The location of stations sampled during
R/V Akvanavt
cruises in 1997, 1999-2002.
correspond strictly to the boundaries on θ-S diagram (Fig. 4a). Temperature-
salinity relationship in the Black Sea is a result of large-scale external factors
such as water and heat balance of the basin. Physical mixing processes dominate
over the
in situ
sulphide production by sulphate-reducing bacteria. Therefore
the depth distribution of dissolved sulphide corresponds strictly to the existing
θ-S structure of the water column.
Our 605 simultaneous measurements of H
2
S concentrations and density
(451 data points in summer and 148 data points in winter) show the following
regression curve between H
2
S (mM) and relative density σ
θ
=σ
insitu
-1000 (kg
m
−
3
) [61]:
3
2
H
2
S
=
0.261σ
θ
−
12.716σ
θ
+
206.573σ
θ
−
1119.01
In the upper part of the sulphide zone the correlation between H
2
Sand
σ
θ
is smaller due to a larger hydrophysical inhomogeneity of the upper 300
m (Fig. 5). The location of the upper sulphide boundary and distribution of
