Physical Oceanography, Vol. 13, No. 5, 2003
MATHEMATICAL MODELING OF MARINE SYSTEMS
AGENT-BASED MARINE-ECOSYSTEMS MODELING
I. E. Timchenko, E. E. Sovga, E. M. Igumnova, and S. M. Solodova
We propose a new information technology aimed at modeling of biochemical processes in ma-
rine ecosystems and based on the use of logical operators of control (intelligent agents) in the dy-
namic equations of the models. We develop a conceptual model of an ecosystem reflecting the
interaction of 17 biochemical processes and 5 external factors. The equations of the model are
obtained by the method of adaptive balance of causes (ABC method), which enables one to sim-
ulate complex scenarios of the processes running in the investigated systems and guarantees the
possibility of robust calculations. Some examples of the behavior of ecosystems under the con-
ditions of deficiency of oxygen caused by the action of natural and anthropogenic factors are pre-
sented. As a result, it is possible to make a conclusion that the combined application of the ABC-
equations and intelligent agents of control in models of marine ecosystems is quite promising.
The development of the theory of complex systems and, in particular, the theory of artificial intelligence, is
an important problem of contemporary natural science. Marine ecosystems are also systems of this sort in view
of the great number of interacting factors specifying the dynamics of hydrophysical and biochemical processes in
the ecosystems. Hence, some results of the theory of artificial intelligence can successfully be used in the con-
struction of dynamic models of marine ecosystems and for the development of information technologies of
control over the processes running in these systems .
As an example, we can mention the application of logical operators of control in the algorithms used for the
solution of equations in the models of ecosystems. In view the great variety of external factors affecting natural
ecosystems and different types of response of the ecosystems to the action of these factors, it is often necessary
to have a possibility of switching between different values of some parameters of the models. For this reason,
the models of ecosystems must include, parallel with traditional sets of dynamic equations, the so-called intelli-
gent control agents . In fact, these intelligent agents (or simply agents) can be regarded as, to a certain extent,
independent parts of the general model of an ecosystem. Their role is to monitor the variations of the character-
istics of some processes running in the ecosystem and perform the prescribed functions of control over the par-
ameters of model.
This idea serves as a basis of the ABC AGENT information technology developed in [3, 4] and numerous
other works cited therein. This technology enables one to predict possible scenarios of development of the pro-
cesses in ecological economical systems taking into account the action of numerous external actions and admits
changes in the structure of internal links in the system. Thus, we actually model open dynamical systems capa-
ble of adaptation to the action of external factors by adjusting their internal parameters and giving adequate re-
sponses. Clearly, these properties are typical of systems of living organisms in marine media whose existence is
simply impossible without the mechanisms of monitoring the external conditions and adaptation to their changes.
Marine Hydrophysical Institute, Ukrainian Academy of Sciences, Sevastopol. Translated from Morskoi Gidrofizicheskii Zhurnal,
63–80, September–October, 2003. Original article submitted July 17, 2002.
0928-5105/03/1305–0299 $25.00 © 2003 Plenum Publishing Corporation 299