Abstract
In urban river management, 'controlling the river flow', 'maintaining the river basin' and 'preserving the ecological environment' are the most important components. However, these are not necessarily considered at simultaneously in practical phases. Each of the components is handled individually. In this paper, a mathematical model for analyzing the relationship among the components is proposed. The relationships among elements in the components are modeled with differential equation. By analyzing the characteristics of equilibriums and their convergence paths, possible symbiotic dynamics of socio- and biospheres are considered. As one of the implications of scenario analysis, it is revealed that if local people engage in activities that improve the river environment for a purpose of relaxation, the balance of the biosphere would eventually change, which would not bring about a good symbiotic state for socio- and biospheres.
