Dynamics of a model of polluted lakes via fractal–fractional operators with two different numerical algorithms.

We employ Mittag-Leffler type kernels to solve a system of fractional differential equations using fractal–fractional (FF) operators with two fractal and fractional orders. Using the notion of FF-derivatives with nonsingular and nonlocal fading memory, a model of three polluted lakes with one source of pollution is investigated. The properties of a non-decreasing and compact mapping are used in order to prove the existence of a solution for the FF-model of polluted lake system. For this purpose, the Leray–Schauder theorem is used. After exploring stability requirements in four versions, the proposed model of polluted lakes system is then simulated using two new numerical techniques based on Adams–Bashforth and Newton polynomials methods. The effect of fractal–fractional differentiation is illustrated numerically. Moreover, the effect of the FF-derivatives is shown under three specific input models of the pollutant: linear, exponentially decaying, and periodic. • Mittag-Leffler fractal–fractional (FF) modeling of polluted lakes. • Well posedness of the polluted lake system with nonsingular and nonlocal fading memory. • Stability of the polluted lakes system. • New numerical techniques based on Adams–Bashforth and Newton polynomials methods. • The effect of linear, exponentially decaying, and periodic pollutants. [ABSTRACT FROM AUTHOR]