Download Presentation

The System of Chemical Elements
Distribution in the Hydrosphere
Vyacheslav D. Korzh
P. P. Shirshov Institute of Oceanology Russian Academy of Sciences, Moscow, Russia
The chemical elements composition in the ocean is a result of substance migration and transformation on river-sea and ocean- atmosphere boundaries (Korzh 1974).
Stability of these processes is the main condition of the hydrosphere ecosystems stability.
Fig. 1. Average concentrations of the chemical elements in the ocean and their types of distribution: 1) conservative; 2) nutrienttype; 3) litho-generative
Today the problems of techno-sphere impact on the biosphere, optimization of their interaction, projection of environmental
impact of techno-generative accidents, and mitigation of their consequences require new approaches to study mass transfer
and transformation of substances in the hydrosphere. Chemical elements composition of oceanic water is a fundamental multidimensional constant for our planet (fig.1).
Fig. 4. The System of chemical elements distribution in the hydrosphere.
Types of distribution in the ocean: 1) conservative; 2) nutrient-type; 3) litho-generative.
In this plot elements form groups reflecting the similarity of their properties. τ value ~40000 years (the residence time of water in
the ocean) separates conservatively and non-conservatively distributed elements. Elements adjacent to this line have a nutrienttype distribution in the ocean that allows establishing their main feature: a similarity of their concentrations in oceanic and river
water. The figure also shows litho-generative elements, which are characterized by the loss of the major part of their river input
at the river – sea boundary zone. The line connecting Cl, Na, Br, B, Sr, Rb, Mo, U, Cs, W, and Au shows the elements, whose
dynamics is mainly controlled by their cyclic migration in the system ocean – atmosphere – continent – ocean.
The System shown in Figure 4 indicates some relationship between three main geochemical parameters of the dissolved forms of
chemical elements in the hydrosphere: 1) average concentration in the ocean, 2) average concentration in the river runoff and 3)
the type of distribution in oceanic water. This allows (using knowledge of two of these parameters) to gain theoretical knowledge
of the third (Korzh 2008, 2012).
The presented System is sufficient for the whole set of chemical elements and for the whole range of observed concentrations
(12 orders of magnitude). It even allows to predict with a great precision the values of the annual river transport of dissolved
Be, C, N, Ge, Tl, Re, to refine such estimates for P, V, Zn, Br, I, and to determine the character of distribution in the ocean for Au
and U. Furthermore, the System allowed to obtain theoretically the reliable data on the natural (not affected by anthropogenic
influence) average concentrations of many elements in the river runoff and use them as ecological reference data. Finally, due to
the long response time of the ocean, the average concentrations of elements and patterns of their distribution in the ocean can
be used to determine of natural (pre-techno-generative) mean concentrations of elements in the river runoff (Korzh 2008, 2012).
Fig. 2. Concentrations ratios of the chemical elements in the ocean and river waters and types of distribution in the ocean:
1) conservative; 2) nutrient-type; 3) litho-generative
Detailed studies revealed three types of chemical element distribution in the ocean:
1) Conservative: concentration normalized to salinity is constant in space and time; 2) Nutrient-type: element
concentration in the surface waters decreases due to the bio-consumption; and 3) Litho-generative: complex character
of distribution of elements, which enter the ocean with the river runoff and interred almost entirely in sediments.
We to determine dependence between concentrations of the chemical elements in the ocean and river waters and
distribution in the ocean (fig. 2) (Korzh 2008)
Conservative type of distribution in the ocean –
CA(ocean) > CA(river)
Nutrient-type of distribution in the ocean –
CA(ocean)~ CA(river)
Litho-generative type of distribution in the ocean – CA(ocean)< CA(river)
types of
Fig.3. The relationship
between average
elemental compositions
for oceanic water and
river water
The correlation between the chemical compositions of the lithosphere and the ocean is relatively weak (r = 0.68) while for river
and oceanic water it is high (r = 0.94) (fig. 3).
We conclude that biogeochemical features of each element determine by the relationship between its average
concentration in the ocean and the intensity of its migration through hydrosphere boundary zones (Korzh
2008, 2012). In Figure 4 we show intensities of global migration and average concentrations in the ocean in the coordinates
lgCocean– lgτ ocean, where Cocean is an average element concentration and τ ocean is its residual time in the ocean. Lines parallel
to the X-axis show concentrations of dissolved forms of elements in the ocean (mole/l). Lines parallel to the Y-axis show
a residual time of dissolved forms of these elements in the ocean and are the geometrical locus of constant ratios between
concentration in oceanic and river water. Lines at 45° to both coordinate axes show average concentrations of dissolved
elements in the river runoff (mole/l).
CONCLUSIONS
It was found that the correlati on between elemental compositions of the
lithosphere and the ocean is relatively weak (r = 0.68) while elemental
compositions of river water and oceanic water has a strong correlation
(r = 0.94). The type of this non-linear relationship was found. This result provides
important guidelines for the solution of both biogeochemical and ecological
problems. Developed systematic methodology gives the chance to describe
and model sufficiently the whole hydrosphere as a complex dynamic system
with numerous hydrodynamic, chemical, biological and other processes. Matter
exchange and transformation at the biogeochemical barriers (i.e. in the zones
of “life concentration”, such as river – sea, ocean – atmosphere) are of crucial
importance among these processes. These processes are responsible for the
constancy of the elemental composition of the ocean, observed features of an
average chemical composition of bottom sediments, and so on.
The system of chemical elements distribution in the hydrosphere constructed
on the base of a new methodology satisfies the criteria of sufficiency and is
sufficient for the whole set of chemical elements and for the whole range of
observed concentrations (12 orders of magnitude). It has not only interpretational
possibilities, but prognostic as well. The system allowed to obtain theoretically
the reliable data on the natural (not affected by anthropogenic influence) average
concentrations of many elements in the river runoff. These concentrations have
to be used as ecological reference data. The geochemical system gives an insight
into the errors in our view of the elemental composition of the hydrosphere. Due
to the great response time of the ocean, mean concentrations of elements and
patterns of their distribution in the ocean can be used as a main reference data
for the determination of natural (unchanged) average concentrations of elements
which were not studied before the global degradation of the hydrosphere.
References
1. Korzh V.D. Some general laws governing the turnover of substance within the ocean-atmosphere-continent-ocean cycle.//
Journal de Recherches Atmospheriques. 1974. Vol.8. N 3-4. P.653-660.
2. Korzh V. The general laws in the formation of the elemental composition of the Hydrosphere and Biosphere.// J. Ecologica,
Vol. XV, 2008. P. 13-21.
3. Korzh V.D. Determination of general laws of elemental composition in Hydrosphere // Water: chemistry & ecology, Journal of
water science and its practical application. № 1, 2012, p. 56-62.
Vyacheslav Korzh. P. P. Shirshov Institute of Oceanology Russian Academy of Sciences, Moscow, Russia. E-mail: [email protected]