Siberian Federal University

Issue

Journal of Siberian Federal University. Biology. 2025 18 (4)

Authors

Bartsev, Sergey I.; Degermendzhi, Andrey G.; Saltykov, Mikhail Y.

Contact information

Bartsev, Sergey I.: Institute of Biophysics SB RAS Federal Research Center “Krasnoyarsk Science Center SB RAS” Krasnoyarsk, Russian Federation; ORCID: 0000-0003-0140-4894; Degermendzhi, Andrey G. : Institute of Biophysics SB RAS Federal Research Center “Krasnoyarsk Science Center SB RAS” Krasnoyarsk, Russian Federation; ORCID: 0000-0001-8649-5419; Saltykov, Mikhail Y.: Institute of Biophysics SB RAS Federal Research Center “Krasnoyarsk Science Center SB RAS” Krasnoyarsk, Russian Federation; ; ORCID: 0009-0008-4225-4531

Keywords

mathematical modeling; greenhouse gases; ecosystem stability

Abstract

The biosphere is a “patchwork” of regional ecosystems the interactions between which are weaker than within the ecosystems, but, nevertheless, can influence their dynamics. The main channel of interaction between such ecosystems is the atmosphere, which transports carbon dioxide. Research shows that the local concentration of carbon dioxide may differ considerably from the global average and exert a substantial effect on plants. To assess the contribution of ecosystems to the global dynamics of greenhouse gases, it is useful to create a mathematical model of regional ecosystems interacting through the atmosphere, and that was the purpose of the current study. The dynamics of the regional ecosystem was described by a point model that included 6 variables: the mass of carbon (Gt) in the atmosphere, in terrestrial plant biomass, in soil organic matter, and in soil microflora, and the atmospheric and soil temperatures. One of the problems of applying the qualitative theory of differential equations to nonlinear systems of high dimension is the search for a stationary solution. The present study proposes a way to circumvent this problem by using the current indicators of the biosphere as stationary ones. The Lyapunov stability of the steady state found in this way was estimated by localizing the eigenvalues of the matrix of the linearized system and numerically integrating the equations of the model. The results show that the stationary values of the model variables, equal to the estimates of the real biosphere values, can be unstable in a fairly wide range of values of the model parameters. At the same time, the greatest stability of the regional ecosystem model is expected at steady-state biomass values equal to half of the limiting capacity of the medium. The interaction with an external atmospheric pool stabilizes the system and practically eliminates the occurrence of self-oscillatory modes and threshold switching. However, analytical estimates and computational experiments suggest that the interaction of eco-climatic systems through a common air pool may lead to various consequences, from the complete absence of any effect to the damping of relaxation oscillations

Pages

578–601

EDN

MBBBXJ

Paper at repository of SibFU

https://elib.sfu-kras.ru/handle/2311/158031

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).