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Ni FJ, Arhonditsis GB. Examination of the effects of toxicity and nutrition on a two prey-predator system with a metabolomics-inspired model. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Chaudhary H, Khan A, Nigar U, Kaushik S, Sajid M. An Effective Synchronization Approach to Stability Analysis for Chaotic Generalized Lotka–Volterra Biological Models Using Active and Parameter Identification Methods. ENTROPY 2022; 24:e24040529. [PMID: 35455192 PMCID: PMC9032272 DOI: 10.3390/e24040529] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/05/2022] [Accepted: 04/07/2022] [Indexed: 12/04/2022]
Abstract
In this manuscript, we systematically investigate projective difference synchronization between identical generalized Lotka–Volterra biological models of integer order using active control and parameter identification methods. We employ Lyapunov stability theory (LST) to construct the desired controllers, which ensures the global asymptotical convergence of a trajectory following synchronization errors. In addition, simulations were conducted in a MATLAB environment to illustrate the accuracy and efficiency of the proposed techniques. Exceptionally, both experimental and theoretical results are in excellent agreement. Comparative analysis between the considered strategy and previously published research findings is presented. Lastly, we describe an application of our considered combination difference synchronization in secure communication through numerical simulations.
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Affiliation(s)
- Harindri Chaudhary
- Department of Mathematics, Jamia Millia Islamia, New Delhi 110025, India; (H.C.); (A.K.); (U.N.)
- Department of Mathematics, Deshbandhu College, New Delhi 110019, India
| | - Ayub Khan
- Department of Mathematics, Jamia Millia Islamia, New Delhi 110025, India; (H.C.); (A.K.); (U.N.)
| | - Uzma Nigar
- Department of Mathematics, Jamia Millia Islamia, New Delhi 110025, India; (H.C.); (A.K.); (U.N.)
| | - Santosh Kaushik
- Department of Mathematics, Bhagini Nivedita College, University of Delhi, New Delhi 110043, India;
| | - Mohammad Sajid
- Department of Mechanical Engineering, College of Engineering, Qassim University, Buraydah 51452, Saudi Arabia
- Correspondence:
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Visha A, Gandhi N, Bhavsar SP, Arhonditsis GB. Assessing mercury contamination patterns of fish communities in the Laurentian Great Lakes: A Bayesian perspective. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 243:777-789. [PMID: 30224205 DOI: 10.1016/j.envpol.2018.07.070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 07/15/2018] [Accepted: 07/16/2018] [Indexed: 05/27/2023]
Abstract
We examine the spatio-temporal trends of mercury, a well-known global legacy contaminant, in eleven fish species across all of the Canadian Great Lakes. These particular fish species are selected based on their ecological, commercial, and recreational importance to the biodiversity and fishing industry of the Great Lakes. We present a two-pronged Bayesian methodological framework to rigorously assess mercury temporal trends across multiple fish species and locations. In the first part of our analysis, we develop dynamic linear models to delineate the total mercury levels and rates of change, while explicitly accounting for the covariance between fish length and mercury levels in fish tissues. We then use hierarchical modelling to evaluate the spatial variability of mercury contamination between nearshore and offshore locations, as well as to examine the hypothesis that invasive species have induced distinct shifts on fish mercury contamination trends. Our analysis suggests that the general pattern across the Great Lakes was that the elevated mercury concentrations during the 1970s had been subjected to a declining trend throughout the late 1980s/early 1990s, followed by a gradual stabilization after the late 1990s/early 2000s. The declining trend was more pronounced with top fish predators, whereas benthivorous fish species mainly underwent wax-and-wane cycles with a weaker evidence of a long-term declining trend. Historically contaminated regions, designated as Areas of Concern, and bays receiving riverine inputs are still characterized by mercury concentrations that can lead to consumption restrictions. Lake Erie displayed the lowest mercury levels across all the fish species examined. However, several species of commercial importance showed a reversing (increasing) trend in the 2000s, although their current levels do not pose any major concerns for consumption advisories. These recent trend reversals can be linked with systematic shifts in energy trophodynamics along with the food web alterations induced from the introduction of non-native species, and the potentially significant fluxes from the atmosphere.
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Affiliation(s)
- Ariola Visha
- Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, M1C 1A4, Canada
| | - Nilima Gandhi
- Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, M1C 1A4, Canada
| | - Satyendra P Bhavsar
- Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, M1C 1A4, Canada; Ontario Ministry of Environment, Conservation and Parks, Toronto, Ontario, M9P 3V6, Canada
| | - George B Arhonditsis
- Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, M1C 1A4, Canada.
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Wagner ND, Simpson AJ, Simpson MJ. Sublethal metabolic responses to contaminant mixture toxicity in Daphnia magna. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2018; 37:2448-2457. [PMID: 29920755 DOI: 10.1002/etc.4208] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/09/2018] [Accepted: 06/13/2018] [Indexed: 06/08/2023]
Abstract
Anthropogenic activity is increasing the presence of contaminants that enter waterways through wastewater effluent and urban and/or agricultural runoff, generally in complex mixtures. Depending on the mode of action of the individual contaminant within the mixture, toxicity can occur due to contaminants having similar or dissimilar modes of action. However, it is unknown how the metabolome responds to sublethal contaminant mixtures in the keystone genus Daphnia. In the present study we examined D. magna metabolic responses to acute sublethal exposure of propranolol, carbamazepine, and perfluorooctanesulfonic acid (PFOS) as well as in binary (propranolol-carbamazepine, propranolol-PFOS, carbamazepine-PFOS) and tertiary mixtures (carbamazepine-propranolol-PFOS), all at 10% of the median lethal concentration of the population (LC50). The metabolome was measured using 1 H nuclear magnetic resonance (NMR) and characterized using principal component analysis, regression analysis, and fold changes in metabolite relative to the unexposed (control) group. The averaged principal component analysis scores plots revealed that carbamazepine-PFOS and carbamazepine-propranolol-PFOS exposures were significantly different from the control treatment. After normalizing the toxicity of each contaminant, we found that some metabolites responded monotonically, whereas others displayed a nonmonotonic response with increasing toxicity units. The single contaminant exposures and 2 binary mixtures (propranolol-carbamazepine, and propranolol-PFOS) resulted in minimal changes in the identified metabolites, whereas the carbamazepine-PFOS and carbamazepine-propranolol-PFOS displayed increases in several amino acid metabolites and decreases in glucose. Overall, our results highlight the sensitivity of the metabolome to distinguish the composition of the contaminant mixtures, with some mixtures displaying heightened responses versus others. Environ Toxicol Chem 2018;37:2448-2457. © 2018 SETAC.
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Affiliation(s)
- Nicole D Wagner
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, Canada
| | - André J Simpson
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Myrna J Simpson
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto, Toronto, Ontario, Canada
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Dannemann T, Boyer D, Miramontes O. Lévy flight movements prevent extinctions and maximize population abundances in fragile Lotka-Volterra systems. Proc Natl Acad Sci U S A 2018; 115:3794-3799. [PMID: 29581271 PMCID: PMC5899458 DOI: 10.1073/pnas.1719889115] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Multiple-scale mobility is ubiquitous in nature and has become instrumental for understanding and modeling animal foraging behavior. However, the impact of individual movements on the long-term stability of populations remains largely unexplored. We analyze deterministic and stochastic Lotka-Volterra systems, where mobile predators consume scarce resources (prey) confined in patches. In fragile systems (that is, those unfavorable to species coexistence), the predator species has a maximized abundance and is resilient to degraded prey conditions when individual mobility is multiple scaled. Within the Lévy flight model, highly superdiffusive foragers rarely encounter prey patches and go extinct, whereas normally diffusing foragers tend to proliferate within patches, causing extinctions by overexploitation. Lévy flights of intermediate index allow a sustainable balance between patch exploitation and regeneration over wide ranges of demographic rates. Our analytical and simulated results can explain field observations and suggest that scale-free random movements are an important mechanism by which entire populations adapt to scarcity in fragmented ecosystems.
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Affiliation(s)
- Teodoro Dannemann
- Laboratorio de Ecoinformática, Instituto de Conservación, Biodiversidad y Territorio, Facultad de Ciencias Forestales y Recursos Naturales, Universidad Austral de Chile, 5110566 Valdivia, Chile
- Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, 6513677 Santiago, Chile
- Instituto de Ecología y Biodiversidad, 7800003 Santiago, Chile
- Instituto de Física, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
| | - Denis Boyer
- Instituto de Física, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico;
- Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
| | - Octavio Miramontes
- Instituto de Física, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
- Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico
- Departamento de Matemáticas Aplicadas, Escuela Técnica Superior de Ingenieria Aeronáutica y del Espacio, Universidad Politécnica de Madrid, 28040 Madrid, Spain
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Robson BJ, Lester RE, Baldwin DS, Bond NR, Drouart R, Rolls RJ, Ryder DS, Thompson RM. Modelling food-web mediated effects of hydrological variability and environmental flows. WATER RESEARCH 2017; 124:108-128. [PMID: 28750285 DOI: 10.1016/j.watres.2017.07.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/14/2017] [Accepted: 07/15/2017] [Indexed: 06/07/2023]
Abstract
Environmental flows are designed to enhance aquatic ecosystems through a variety of mechanisms; however, to date most attention has been paid to the effects on habitat quality and life-history triggers, especially for fish and vegetation. The effects of environmental flows on food webs have so far received little attention, despite food-web thinking being fundamental to understanding of river ecosystems. Understanding environmental flows in a food-web context can help scientists and policy-makers better understand and manage outcomes of flow alteration and restoration. In this paper, we consider mechanisms by which flow variability can influence and alter food webs, and place these within a conceptual and numerical modelling framework. We also review the strengths and weaknesses of various approaches to modelling the effects of hydrological management on food webs. Although classic bioenergetic models such as Ecopath with Ecosim capture many of the key features required, other approaches, such as biogeochemical ecosystem modelling, end-to-end modelling, population dynamic models, individual-based models, graph theory models, and stock assessment models are also relevant. In many cases, a combination of approaches will be useful. We identify current challenges and new directions in modelling food-web responses to hydrological variability and environmental flow management. These include better integration of food-web and hydraulic models, taking physiologically-based approaches to food quality effects, and better representation of variations in space and time that may create ecosystem control points.
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Affiliation(s)
- Barbara J Robson
- CSIRO Land and Water, GPO Box 1700, Canberra, ACT, 2601, Australia.
| | - Rebecca E Lester
- Centre for Regional and Rural Futures, Deakin University, Locked Bag 20000, Geelong, Vic, 3220, Australia.
| | - Darren S Baldwin
- CSIRO Land and Water, GPO Box 1700, Canberra, ACT, 2601, Australia; The Murray-Darling Freshwater Research Centre, La Trobe University, PO Box 821, Wodonga, Vic, 3689, Australia; Charles Sturt University, Thurgoona, NSW, 2640, Australia
| | - Nicholas R Bond
- The Murray-Darling Freshwater Research Centre, La Trobe University, PO Box 821, Wodonga, Vic, 3689, Australia
| | - Romain Drouart
- CSIRO Land and Water, GPO Box 1700, Canberra, ACT, 2601, Australia; Ecole des Mines d'Alès, 6 Avenue de Clavières, 30319, Alès Cedex, France
| | - Robert J Rolls
- Institute for Applied Ecology, University of Canberra, Canberra, ACT, 2601, Australia
| | - Darren S Ryder
- School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Ross M Thompson
- Institute for Applied Ecology, University of Canberra, Canberra, ACT, 2601, Australia
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Ni FJ, Kelly NE, Arhonditsis GB. Towards the development of an ecophysiological Daphnia model to examine effects of toxicity and nutrition. ECOL INFORM 2017. [DOI: 10.1016/j.ecoinf.2017.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Kariuki MN, Nagato EG, Lankadurai BP, Simpson AJ, Simpson MJ. Analysis of Sub-Lethal Toxicity of Perfluorooctane Sulfonate (PFOS) to Daphnia magna Using ¹H Nuclear Magnetic Resonance-Based Metabolomics. Metabolites 2017; 7:metabo7020015. [PMID: 28420092 PMCID: PMC5487986 DOI: 10.3390/metabo7020015] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/05/2017] [Accepted: 04/12/2017] [Indexed: 01/29/2023] Open
Abstract
1H nuclear magnetic resonance (NMR)-based metabolomics was used to characterize the response of Daphnia magna after sub-lethal exposure to perfluorooctane sulfonate (PFOS), a commonly found environmental pollutant in freshwater ecosystems. Principal component analysis (PCA) scores plots showed significant separation in the exposed samples relative to the controls. Partial least squares (PLS) regression analysis revealed a strong linear correlation between the overall metabolic response and PFOS exposure concentration. More detailed analysis showed that the toxic mode of action is metabolite-specific with some metabolites exhibiting a non-monotonic response with higher PFOS exposure concentrations. Our study indicates that PFOS exposure disrupts various energy metabolism pathways and also enhances protein degradation. Overall, we identified several metabolites that are sensitive to PFOS exposure and may be used as bioindicators of D. magna health. In addition, this study also highlights the important utility of environmental metabolomic methods when attempting to elucidate acute and sub-lethal pollutant stressors on keystone organisms such as D. magna.
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Affiliation(s)
- Martha N Kariuki
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada.
| | - Edward G Nagato
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada.
| | - Brian P Lankadurai
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada.
| | - André J Simpson
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada.
| | - Myrna J Simpson
- Environmental NMR Centre and Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada.
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