Principles of Simulation of Invasion Stages with Allowance for Solar Cycles.

A method for constructing models of the scenario simulation of special situations in biophysical systems with allowance for the effect of changes in the physics of the Sun is proposed. Tools for representing hybrid computational structures for computer models of scenarios of invasion of species with a high reproductive potential into a new habitat by analogy with physical phase transitions are being intentionally developed. Our analysis shows that the dynamics of population insect invasions has much in common with the development of the modern pandemic: many series of repeated activity outbreaks are observed in both forest pests and new strains of coronavirus. After a long, but false and deceptive, damping, local peaks reappear, as has been observed for the invasive North American Lymantria dispar moth pest. Physical models of oscillators need to be significantly improved, since biosystems are self-regulating. We have formed a calculation scheme from variants of the right-hand sides of differential equations with predicates for their situational switching at the event transformation points. We have simulated the extreme development and analyzed options in the sequence of stages of crisis processes. The developed invasion modeling principle is based on the description of stages and phase changes during the evolution of processes occurring under the dispersal of alien species. We have developed switching schemes for a set of forms for the right-hand sides of the equations correlated with the invasion stages. The modeled process is divided into stages: introduction of a small group of individuals, hidden existence, adaptive takeover of a habitat, population explosion, crisis, and new oscillating equilibrium. There is a hypothesis that changes in the pest population are influenced by the physical effect of cyclic solar activity. Computer-simulation experiments in scenarios for situations of pulsating pest invasions include the factor of periodic changes in the solar constant, for example, in the Hale cycle. The factor of cyclicity of the solar constant, according to the Schatten's model, has been included in the auxiliary equation of our hybrid system. Using the method for organizing hybrid structures, we have studied the phase variants of the invasive phenomena leading to pulsating outbreaks of the Lymantria dispar pest. Analysis of the hybrid model with a lag argument does not allow us to say that the periodic solar activity is the most important physical factor in triggering pulsating outbreaks. The rates of biota recovery and adaptation of natural enemies are more important factors of triggering the outbreak activity. [ABSTRACT FROM AUTHOR]