Different routes to chaos and period-bubbling phenomenon: A study of a water-vegetation model
摘要
In ecosystems, vegetation plays many vital roles, e.g., controlling energy flow, maintaining biodiversity, regulating climate, etc., which significantly contribute to the ecosystem’s overall health and balance. Rainfall infiltration into the soil determines the water availability, while the water absorbed by the vegetation influences its growth. In the present study, we investigate the dynamics of a discrete-time water-vegetation model to capture the individual and simultaneous effects of rainfall and water absorption by vegetation. One of the most fascinating outcomes of the study is the transition of the system from a stable state to chaos via different routes. Another interesting feature observed in the system is the period-bubbling phenomenon. The isoperiodic and the largest Lyapunov exponent diagrams unravel a lot of information about the system’s dynamics in the parameter plane, including the appearance of organized periodic structures like shrimp-shaped domains and Arnold tongues. Another intriguing feature of the system is the coexistence of two periodic attractors with fractal basin boundaries. Our findings suggest that rainfall plays a significant role in the variation of vegetation density, which ultimately shapes an ecosystem’s structure, function, and resilience.