Мodeling of the Sea Upper Layer Ecosystem Fields by the Adaptive Balance of Causes Method

Abstract

A method for constructing the sea upper layer ecosystem fields, based on negative feedbacks in the ecosystem model, which provide mutual adaptation of biochemical processes taking into account resource limitations and external influences, is considered. This method allows us to construct causeand-effect dependencies between the processes in complex ecosystems using negative feedbacks between the ecosystem model variables and rates of their change. It is shown that such an approach retains material balances of biochemical reactions in the ecosystem and increases sensitivity of adaptive models to the data of observations assimilated in them. A method for assimilation of calculated data on marine environment dynamics in adaptive models of marine ecosystems consisting in simultaneous adjustment of biochemical process values to the data of satellite observations and previously obtained assessments of marine environment advection and diffusion is proposed. The method is illustrated by the examples of constructing the charts of phytoplankton, zooplankton, bio-resource and oxygen concentrations for the shelf regions of the north-western Вlack Sea. Satellite observation data on the sea surface temperature and chlorophyll-a concentration as well as the assessments of the substance simulated advection and diffusion resulted from the hydrodynamic model are used as the external sources of influences. The coefficients of intra-system influences in ecosystem are assessed by the data of long-term observations carried out in this area. The charts of spatial-temporal fields of biochemical processes in the upper sea layer, coordinated with the charts of horizontal currents and satellite observations of chlorophyll-a concentrations are constructed. The conclusion that the ecosystem adaptive models should be advisably applied for obtaining the assessments of spatial distribution of the bio-chemical substance concentrations in the sea upper layer ecosystem is drawn.