Exploring the structural sensitivity in some spatially-explicit models of ecological dynamics Kalyan Manna, Malay Banerjee, Sergei Petrovskii Chaos Solitons and Fractals, 2026 Mathematical models are frequently used to infer predictions about population dynamics in real ecosystems. However, parametrization of intra- and interspecific interactions is usually approximate, as the amount and quality of ecological information is never sufficient to make a ‘precise’ decision about the mathematical function(s) to use. The question therefore arises as to how sensitive the model properties can be with regard to the choice of the function - the problem known as “structural sensitivity”. In this article, we explore the structural sensitivity of a predator–prey model with additive Allee effect in prey growth and density-dependent death rate for predator. We test the sensitivity of both temporal (non-spatial) and spatiotemporal (spatially-explicit) models using three qualitatively similar but numerically different parametrizations of the predator functional response, such as Holling type II (fraction-linear), Ivlev (exponential) and hyperbolic (trigonometric) functions. Using an array of the analytical and numerical tools, we show that both the temporal and spatiotemporal dynamics can be qualitatively different for the three chosen parametrizations. Also, our study clearly reveals that any hierarchical ranking of these parametrizations according to their destabilizing potential is not possible.
EFFECTS OF SPATIOTEMPORAL, TEMPORAL AND SPATIAL NONLOCAL PREY COMPETITIONS ON POPULATION DISTRIBUTIONS FOR A PREY-PREDATOR SYSTEM WITH GENERALIST PREDATION Kalyan Manna, Swadesh Pal, Malay Banerjee Discrete and Continuous Dynamical Systems Series B, 2026 Conventional wisdom suggests that a prey-predator system with a generalist predator exhibits more stable dynamics than with a specialist predator. However, recent developments show that the presence of a generalist predator can lead to comparatively complex dynamics, including bistability, tristability, and several local as well as global bifurcations. In this paper, we study the dynamics of both local and nonlocal models of prey-predator interactions with generalist-type predation. Nonlocal intra-specific prey competition is assumed to be spatiotemporal, purely temporal, or purely spatial in nature. Also, we primarily aim to understand the resulting system dynamics under conditions of subpar and limited substitute food options available to the generalist predator. We first ensure that the local model is well-posed, and then provide the conditions for the existence and non-existence of spatially heterogeneous steady state solutions by using the maximum principle, Poincaré inequality and Leray-Schauder degree theory. Further, we derive the conditions for Turing instability in both the local and nonlocal models by using the linear analysis. We then illustrate a wide class of stationary and dynamic patterns obtained through numerical simulations for all the considered models, where the choice of the parametric domain is partially guided by the analytical results. This study reveals that the nonlocal model with purely spatial kernel admits spatial-Hopf bifurcation which gives rise to population oscillations around a 'ghost attractor', whereas this phenomenon does not occur in the other models.
On the structural sensitivity of some diffusion–reaction models of population dynamics Kalyan Manna, Malay Banerjee, Sergei Petrovskii Physica D Nonlinear Phenomena, 2024 In mathematical ecology, it is often assumed that properties of a mathematical model are robust to specific parameterization of functional responses, in particular preserving the bifurcation structure of the system, as long as different functions are qualitatively similar. This intuitive assumption has been challenged recently (Fussmann & Blasius, Community response to enrichment is highly sensitive to model structure, Biology Letters 1:9-12, 2005). Having considered the prey-predator system as a paradigm of nonlinear population dynamics, it has been shown that in fact both the bifurcation structure and the structure of the phase space can be rather different even when the component functions are apparently close to each other. However, these observations have so far been largely limited to nonspatial systems described by ODEs. In this paper, our main motivating interest is to investigate whether such structural sensitivity occurs in spatially explicit models of population dynamics, in particular those that are described by PDEs. We consider a prey-predator model described by a system of two nonlinear reaction–diffusion-advection equations where the predation term is parameterized by three different yet numerically close functions. Using some analytical tools along with numerical simulations, we show that the properties of spatiotemporal dynamics are rather different between the three cases, so that patterns observed for one parameterization may not occur for the other two ones.
A generalized distributed delay model for hepatitis B virus infection with two modes of transmission and adaptive immunity: A mathematical study Kalyan Manna, Khalid Hattaf Mathematical Methods in the Applied Sciences, 2022 In this paper, we formulate a generalized hepatitis B virus (HBV) infection model with two modes of infection transmission and adaptive immunity and investigate its dynamical properties. Both the virus‐to‐cell and cell‐to‐cell infection transmissions are modeled by general functions which satisfy some biologically motivated assumptions. Furthermore, the model incorporates three distributed time delays for the production of active infected hepatocytes, mature capsids, and virions. The well‐posedness of the proposed model is established by showing the non‐negativity and boundedness of solutions. Five equilibria of the model are identified in terms of five threshold parameters R0,R1,R2,R3$$ {R}_0,{R}_1,{R}_2,{R}_3 $$ , and R4$$ {R}_4 $$ . Further, the global stability analysis of each equilibrium under certain conditions is carried out by employing suitable Lyapunov function and LaSalle's invariance principle. Finally, we present an example with numerical simulations to illustrate the applicability of our study. Nonetheless, the results obtained in this study are valid for a wide class of HBV infection models.
Spatiotemporal pattern formation in a prey predator model with generalist predator Kalyan Manna, Malay Banerjee Mathematical Modelling of Natural Phenomena, 2022 Generalist predators exploit multiple food sources and it is economical for them to reduce predation pressure on a particular prey species when their density level becomes comparatively less. As a result, a prey-predator system tends to become more stable in the presence of a generalist predator. In this article, we investigate the roles of both the diffusion and nonlocal prey consumption in shaping the population distributions for interacting generalist predator and its focal prey species. In this regard, we first derive the conditions associated with Turing instability through linear analysis. Then, we perform a weakly nonlinear analysis and derive a cubic Stuart-Landau equation governing amplitude of the resulting patterns near Turing bifurcation boundary. Further, we present a wide variety of numerical simulations to corroborate our analytical findings as well as to illustrate some other complex spatiotemporal dynamics. Interestingly, our study reveals the existence of traveling wave solutions connecting two spatially homogeneous coexistence steady states in Turing domain under the influence of temporal bistability phenomenon. Also, our investigation shows that nonlocal prey consumption acts as a stabilizing force for the system dynamics.
Spatiotemporal patterns of social protests: Reaction-diffusion approach A Morozov, K Manna, M Banerjee, S Petrovskii Chaos, Solitons & Fractals 208 (2), 118184 , 2026 2026
Exploring the structural sensitivity in some spatially-explicit models of ecological dynamics K Manna, M Banerjee, S Petrovskii Chaos, Solitons & Fractals 204, 117759 , 2026 2026 Citations: 1
Biological models with nonlocal terms: Future scopes of research: Comment on “Nonlocal models in biology and life sciences: Sources, developments, and applications” by S. Pal … M Banerjee, K Manna, I Gaine Physics of Life Reviews 56, 29-32 , 2026 2026
Effects of spatiotemporal, temporal and spatial nonlocal prey competitions on population distributions for a prey-predator system with generalist predation K Manna, S Pal, M Banerjee Discrete and Continuous Dynamical Systems- Series B 31 (1), 166-197 , 2026 2026
Dynamics of a within-host HIV infection model with adaptive immunity S Samaddar, K Manna, M Banerjee Mathematics for Industry 38, 29-52 , 2024 2024 Citations: 1
On the structural sensitivity of some diffusion-reaction models of population dynamics K Manna, M Banerjee, S Petrovskii Physica D: Nonlinear Phenomena 467, 134220 , 2024 2024 Citations: 12
Dynamics of a prey–predator model with reproductive Allee effect for prey and generalist predator K Manna, M Banerjee Nonlinear Dynamics 112 (9), 7727-7748 , 2024 2024 Citations: 22
A generalized distributed delay model for hepatitis B virus infection with two modes of transmission and adaptive immunity: A mathematical study K Manna, K Hattaf Mathematical Methods in the Applied Sciences 45 (17), 11614-11634 , 2022 2022 Citations: 10
Spatiotemporal pattern formation in a prey-predator model with generalist predator K Manna, M Banerjee Mathematical Modelling of Natural Phenomena 17, 6 , 2022 2022 Citations: 22
Pattern formation in a three-species cyclic competition model K Manna, V Volpert, M Banerjee Bulletin of Mathematical Biology 83 (5), 52 , 2021 2021 Citations: 32
Analytical and numerical detection of traveling wave and wave-train solutions in a prey-predator model with weak Allee effect K Manna, S Pal, M Banerjee Nonlinear Dynamics 100 (3), 2989-3006 , 2020 2020 Citations: 9
Dynamics of a diffusive two-prey-one-predator model with nonlocal intra-specific competition for both the prey species K Manna, V Volpert, M Banerjee Mathematics 8 (1), 101 , 2020 2020 Citations: 32
Modeling the dynamics of hepatitis B virus infection in presence of capsids and immunity K Hattaf, K Manna Studies in Systems, Decision and Control 302, 269-294 , 2020 2020 Citations: 12
Spatiotemporal dynamics of a generalized HBV infection model with capsids and adaptive immunity K Manna, K Hattaf International Journal of Applied and Computational Mathematics 5 (3), 65 , 2019 2019 Citations: 24
Stability of Hopf-bifurcating limit cycles in a diffusion-driven prey-predator system with Allee effect and time delay K Manna, M Banerjee Mathematical Biosciences and Engineering 16 (4), 2411-2446 , 2019 2019 Citations: 19
Stationary, non-stationary and invasive patterns for a prey-predator system with additive Allee effect in prey growth K Manna, M Banerjee Ecological Complexity 36, 206-217 , 2018 2018 Citations: 34
Dynamics of a delayed diffusive HBV infection model with capsids and CTL immune response K Manna International Journal of Applied and Computational Mathematics 4 (5), 116 , 2018 2018 Citations: 18
Combination therapy of pegylated interferon and lamivudine and optimal controls for chronic hepatitis B infection K Manna, SP Chakrabarty International Journal of Dynamics and Control 6 (1), 354-368 , 2018 2018 Citations: 14
A non-standard finite difference scheme for a diffusive HBV infection model with capsids and time delay K Manna Journal of Difference Equations and Applications 23 (11), 1901-1911 , 2017 2017 Citations: 20
Global properties of a HBV infection model with HBV DNA-containing capsids and CTL immune response K Manna International Journal of Applied and Computational Mathematics 3 (3), 2323-2338 , 2017 2017 Citations: 39
MOST CITED SCHOLAR PUBLICATIONS
Chronic hepatitis B infection and HBV DNA-containing capsids: Modeling and analysis K Manna, SP Chakrabarty Communications in Nonlinear Science and Numerical Simulation 22 (1-3), 383-395 , 2015 2015 Citations: 90
Global stability and a non-standard finite difference scheme for a diffusion driven HBV model with capsids K Manna, SP Chakrabarty Journal of Difference Equations and Applications 21 (10), 918-933 , 2015 2015 Citations: 61
Global stability of one and two discrete delay models for chronic hepatitis B infection with HBV DNA-containing capsids K Manna, SP Chakrabarty Computational and Applied Mathematics 36 (1), 525-536 , 2017 2017 Citations: 58
Global properties of a HBV infection model with HBV DNA-containing capsids and CTL immune response K Manna International Journal of Applied and Computational Mathematics 3 (3), 2323-2338 , 2017 2017 Citations: 39
Stationary, non-stationary and invasive patterns for a prey-predator system with additive Allee effect in prey growth K Manna, M Banerjee Ecological Complexity 36, 206-217 , 2018 2018 Citations: 34
Pattern formation in a three-species cyclic competition model K Manna, V Volpert, M Banerjee Bulletin of Mathematical Biology 83 (5), 52 , 2021 2021 Citations: 32
Dynamics of a diffusive two-prey-one-predator model with nonlocal intra-specific competition for both the prey species K Manna, V Volpert, M Banerjee Mathematics 8 (1), 101 , 2020 2020 Citations: 32
Spatiotemporal dynamics of a generalized HBV infection model with capsids and adaptive immunity K Manna, K Hattaf International Journal of Applied and Computational Mathematics 5 (3), 65 , 2019 2019 Citations: 24
Dynamics of a prey–predator model with reproductive Allee effect for prey and generalist predator K Manna, M Banerjee Nonlinear Dynamics 112 (9), 7727-7748 , 2024 2024 Citations: 22
Spatiotemporal pattern formation in a prey-predator model with generalist predator K Manna, M Banerjee Mathematical Modelling of Natural Phenomena 17, 6 , 2022 2022 Citations: 22
Dynamics of a diffusion-driven HBV infection model with capsids and time delay K Manna International Journal of Biomathematics 10 (5), 1750062 (18 pages) , 2017 2017 Citations: 21
A non-standard finite difference scheme for a diffusive HBV infection model with capsids and time delay K Manna Journal of Difference Equations and Applications 23 (11), 1901-1911 , 2017 2017 Citations: 20
Stability of Hopf-bifurcating limit cycles in a diffusion-driven prey-predator system with Allee effect and time delay K Manna, M Banerjee Mathematical Biosciences and Engineering 16 (4), 2411-2446 , 2019 2019 Citations: 19
Dynamics of a delayed diffusive HBV infection model with capsids and CTL immune response K Manna International Journal of Applied and Computational Mathematics 4 (5), 116 , 2018 2018 Citations: 18
Combination therapy of pegylated interferon and lamivudine and optimal controls for chronic hepatitis B infection K Manna, SP Chakrabarty International Journal of Dynamics and Control 6 (1), 354-368 , 2018 2018 Citations: 14
On the structural sensitivity of some diffusion-reaction models of population dynamics K Manna, M Banerjee, S Petrovskii Physica D: Nonlinear Phenomena 467, 134220 , 2024 2024 Citations: 12
Modeling the dynamics of hepatitis B virus infection in presence of capsids and immunity K Hattaf, K Manna Studies in Systems, Decision and Control 302, 269-294 , 2020 2020 Citations: 12
A generalized distributed delay model for hepatitis B virus infection with two modes of transmission and adaptive immunity: A mathematical study K Manna, K Hattaf Mathematical Methods in the Applied Sciences 45 (17), 11614-11634 , 2022 2022 Citations: 10
Analytical and numerical detection of traveling wave and wave-train solutions in a prey-predator model with weak Allee effect K Manna, S Pal, M Banerjee Nonlinear Dynamics 100 (3), 2989-3006 , 2020 2020 Citations: 9
Dynamics and analysis of a model for chronic hepatitis B infection K Manna, SP Chakrabarty Journal of Interdisciplinary Mathematics 20 (2), 339-355 , 2017 2017 Citations: 4