1
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Pal MK, Poria S. Effects of non-local competition on plankton-fish dynamics. CHAOS (WOODBURY, N.Y.) 2021; 31:053108. [PMID: 34240933 DOI: 10.1063/5.0040844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 04/19/2021] [Indexed: 06/13/2023]
Abstract
In ecology, the intra- and inter-specific competition between individuals of mobile species for shared resources is mostly non-local; i.e., competition at any spatial position will not only be dependent on population at that position, but also on population in neighboring regions. Therefore, models that assume competition to be restricted to the individuals at that position only are actually oversimplifying a crucial physical process. For the past three decades, researchers have established the necessity of considering spatial non-locality while modeling ecological systems. Despite this ecological importance, studies incorporating this non-local nature of resource competition in an aquatic ecosystem are surprisingly scarce. To this end, the celebrated Scheffer's tri-trophic minimal model has been considered here as a base model due to its efficacy in describing the pelagic ecosystem with least complexity. It is modified into an integro-reaction-diffusion system to include the effect of non-local competition by introducing a weighted spatial average with a suitable influence function. A detailed analysis shows that the non-locality may have a destabilizing effect on underlying nutrient-plankton-fish dynamics. A local system in a stable equilibrium state can lose its stability through spatial Hopf and Turing bifurcations when strength of a non-local interaction is strong enough, which eventually generates a large range of spatial patterns. The relationship between a non-local interaction and fish predation has been established, which shows that fish predation contributes in damping of plankton oscillations. Overall, results obtained here manifest the significance of non-locality in aquatic ecosystems and its possible contribution to the phenomena of "spatial patchiness."
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Affiliation(s)
- Mrinal Kanti Pal
- Department of Applied Mathematics, University of Calcutta, 92 APC Road, Kolkata 700009, India
| | - Swarup Poria
- Department of Applied Mathematics, University of Calcutta, 92 APC Road, Kolkata 700009, India
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2
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Fausch KD, Nakano S, Kitano S, Kanno Y, Kim S. Interspecific social dominance networks reveal mechanisms promoting coexistence in sympatric charr in Hokkaido, Japan. J Anim Ecol 2020; 90:515-527. [PMID: 33159688 DOI: 10.1111/1365-2656.13384] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 10/23/2020] [Indexed: 11/29/2022]
Abstract
Coexistence of species requires equalizing mechanisms that minimize fitness differences, which are balanced by stabilizing mechanisms that enhance negative intraspecific interactions versus interspecific ones. Here, we develop a simple theoretical framework that allows measuring the relative strength of intraspecific versus interspecific competition in dominance hierarchies. We use it to evaluate mechanisms promoting coexistence between two congeneric charr that compete for foraging positions, which strongly influence density-dependent growth and survival. Agonistic interactions (n = 761) among 71 Dolly Varden Salvelinus malma and whitespotted charr Salvelinus leucomaenis were measured by snorkelling in two pools in the sympatric zone of a Hokkaido stream during two summers. Interspecific dominance hierarchies, analysed using three methods, were closely correlated with fish length but the species treated each other equally. Ranks for the most dominant fish in each pool, determined directly by knockout experiments, were also virtually identical to ranks by length. Similarly, exponential random graph modelling of the social networks provided no evidence that either species was dominant over the other. Instead, larger fish were more likely to win contests, especially over fish of the next lower ranks. These results demonstrated that the two species were nearly ecological equivalents in accessing key resources in this sympatric zone. Nearly identical growth and stable densities over 4 years further supported this inference, although Dolly Varden were a minority (29% of the assemblage), a sign of some fitness difference. Detailed foraging observations coupled with two concurrent studies revealed an effective stabilizing mechanism. Dolly Varden shifted to feeding directly from the benthos when drifting invertebrates declined, a behaviour enhanced by morphological character displacement, thereby partitioning food resources and enhancing intraspecific competition while avoiding agonistic encounters with whitespotted charr. The plurality of evidence indicates that fitness differences between these ecologically equivalent species are small in this local assemblage, and balanced by resource partitioning, a modest stabilizing mechanism that promotes coexistence. The theoretical framework presented here is a useful tool to evaluate the strength of interspecific versus intraspecific competition, which combined with information on trade-offs in ecological performance can contribute to a mechanistic understanding of species coexistence.
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Affiliation(s)
- Kurt D Fausch
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO, USA.,Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
| | - Shigeru Nakano
- Tomakomai Forest Research Station, Hokkaido University Forests, Tomakomai, Hokkaido, Japan.,Center for Ecological Research, Kyoto University, Otsu, Shiga, Japan
| | - Satoshi Kitano
- Nagano Environmental Conservation Research Institute, Kitago, Nagano, Japan
| | - Yoichiro Kanno
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO, USA.,Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
| | - Seoghyun Kim
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO, USA
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3
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Zhou J, Qin B, Zhu G, Zhang Y, Gao G. Long-term variation of zooplankton communities in a large, heterogenous lake: Implications for future environmental change scenarios. ENVIRONMENTAL RESEARCH 2020; 187:109704. [PMID: 32473462 DOI: 10.1016/j.envres.2020.109704] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 05/15/2020] [Accepted: 05/16/2020] [Indexed: 06/11/2023]
Abstract
In recent decades, freshwater ecosystems have been threatened worldwide by multiple simultaneous stressors, including eutrophication, climate change and competing demands for water sources. However, understanding of the long-term variation of zooplankton communities remains limited because long-term observations are lacking. Here, using a long-term (19 year) monitoring dataset, we demonstrate the spatio-temporal variation of zooplankton communities in Lake Taihu, a large, shallow, heterogenous lake in China. With the development of eutrophication, the abundance and biomass of zooplankton first increased from 1998 to 2004, and then exhibited a decreasing trend thereafter. Specifically, the population of rotifer dramatically declined after 2001, while the abundance of copepod and cladoceran showed an increasing trend even though their biomass decreased significantly after 2008. The dominance of small cladocerans (Bosmina coregoni and Ceriodaphnia cornuta) and copepod (Limnothora sinensis) significantly increased with decreasing rotifer density after 2014. Moreover, the zooplankton community structure exhibited heterogenous spatial population dynamics. Cladoceran and rotifer were predominant in cyanobacteria-dominated regions, while a higher proportion of copepod were found in macrophyte-dominated regions. Analyses revealed that zooplankton communities were strongly affected by climate warming and nutrients. These results reinforce previous work demonstrating that the development of eutrophication and climate warming could change the structure of zooplankton community and increase the dominance of small-bodied crustacean. Our findings address the recognized gap in understanding the variation of the zooplankton community in Lake Taihu, and provide an opportunity to evaluate ongoing changes in the zooplankton community related to future environmental change scenarios.
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Affiliation(s)
- Jian Zhou
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, PR China
| | - Boqiang Qin
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, PR China; School of Geography and Ocean Science, Nanjing University, 163 Xianlin Street, Nanjing, 210023, PR China.
| | - Guangwei Zhu
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, PR China
| | - Yunlin Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, PR China
| | - Guang Gao
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, PR China
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4
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Maszczyk P, Babkiewicz E, Ciszewski K, Dabrowski K, Dynak P, Krajewski K, Urban P, Żebrowski M, Wilczynski W. Combined effects of elevated epilimnetic temperature and metalimnetic hypoxia on the predation rate of planktivorous fish. JOURNAL OF PLANKTON RESEARCH 2019; 41:709-722. [PMID: 31768081 PMCID: PMC6862932 DOI: 10.1093/plankt/fbz048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 07/21/2019] [Accepted: 07/30/2019] [Indexed: 06/10/2023]
Abstract
Increased temperature in the epilimnion and hypoxia in the metalimnion of a lake would result in an increase of positive-size-selective fish predation on zooplankton and in turn in a decrease of mean body size in zooplankton populations and communities. We tested this hypothesis in four types of experiments with juvenile rudd (Scardinius erythrophthalmus) foraging on Daphnia longispina in an indoor twin column tank system. In each experiment of the first three types, one column contained one of three types of experimental treatments differing from the control treatment (in the other column) by the following: (i) elevated temperature in the epilimnion, (ii) hypoxia in the metalimnion and (iii) simultaneous elevated temperature in the epilimnion and hypoxia in the metalimnion. In the fourth type of experiment, the gradients of temperature and oxygen concentration in both columns were the same, but prior to the experiments, Daphnia and fish in the control treatment were acclimated to normoxia and, in the experimental treatment, to hypoxia. The results confirmed our hypothesis, since the predation rate of fish was greater in each of the first three experimental treatments than in the control. We did not detect an effect of the acclimation to hypoxia on the predation rate of the fish.
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Affiliation(s)
- Piotr Maszczyk
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
| | - Ewa Babkiewicz
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
| | - Krzysztof Ciszewski
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
| | - Kamil Dabrowski
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
| | - Przemysław Dynak
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
| | - Karol Krajewski
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
| | - Paulina Urban
- LABORATORY OF FUNCTIONAL AND STRUCTURAL GENOMICS, CENTER OF NEW TECHNOLOGIES, UNIVERSITY OF WARSAW, BANACHA 2C, WARSAW 02-097, POLAND
- COLLEGE OF INTER-FACULTY INDIVIDUAL STUDIES IN MATHEMATICS AND NATURAL SCIENCES, UNIVERSITY OF WARSAW, BANACHA 2C, 02-097 WARSAW, POLAND
| | - Marcin Żebrowski
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
| | - Wojciech Wilczynski
- DEPARTMENT OF HYDROBIOLOGY, FACULTY OF BIOLOGY, BIOLOGICAL AND CHEMICAL RESEARCH CENTRE AT UNIVERSITY OF WARSAW, ŻWIRKI I WIGURY 101, 02-089 WARSAW, POLAND
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5
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Lemarre P, Pujo-Menjouet L, Sindi SS. Generalizing a mathematical model of prion aggregation allows strain coexistence and co-stability by including a novel misfolded species. J Math Biol 2018; 78:465-495. [PMID: 30116882 PMCID: PMC6399074 DOI: 10.1007/s00285-018-1280-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 02/20/2018] [Indexed: 11/29/2022]
Abstract
Prions are proteins capable of adopting misfolded conformations and transmitting these conformations to other normally folded proteins. Prions are most commonly known for causing fatal neurodegenerative diseases in mammals but are also associated with several harmless phenotypes in yeast. A distinct feature of prion propagation is the existence of different phenotypical variants, called strains. It is widely accepted that these strains correspond to different conformational states of the protein, but the mechanisms driving their interactions remain poorly understood. This study uses mathematical modeling to provide insight into this problem. We show that the classical model of prion dynamics allows at most one conformational strain to stably propagate. In order to conform to biological observations of strain coexistence and co-stability, we develop an extension of the classical model by introducing a novel prion species consistent with biological studies. Qualitative analysis of this model reveals a new variety of behavior. Indeed, it allows for stable coexistence of different strains in a wide parameter range, and it also introduces intricate initial condition dependency. These new behaviors are consistent with experimental observations of prions in both mammals and yeast. As such, our model provides a valuable tool for investigating the underlying mechanisms of prion propagation and the link between prion strains and strain specific phenotypes. The consideration of a novel prion species brings a change in perspective on prion biology and we use our model to generate hypotheses about prion infectivity.
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Affiliation(s)
- Paul Lemarre
- School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, CA, 95343, USA
| | - Laurent Pujo-Menjouet
- Institut Camille Jordan, Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5208, 43 blvd. du 11 novembre 1918, 69622, Villeurbanne cedex, France.,Team Dracula, INRIA, 69603, Villeurbanne cedex, France
| | - Suzanne S Sindi
- Applied Mathematics School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, CA, 95343, USA.
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6
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Maszczyk P, Babkiewicz E, Czarnocka-Cieciura M, Gliwicz ZM, Uchmański J, Urban P. Ideal free distribution of Daphnia under predation risk-model predictions and experimental verification. JOURNAL OF PLANKTON RESEARCH 2018; 40:471-485. [PMID: 30057433 PMCID: PMC6055580 DOI: 10.1093/plankt/fby024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 05/16/2018] [Accepted: 06/01/2018] [Indexed: 06/08/2023]
Abstract
The vertical distribution of planktonic animals, such as Daphnia, in overlapping gradients of food concentration and risk of visual predation should depend on Daphnia population density and should be the result of the group effect of optimizing decisions taken by each individual (juvenile or adult), trading-off a high growth rate to low mortality risk. We tested this hypothesis by comparing the theoretical distributions from simulations based on an experimentally parameterized, optimizing individual-based model (consistent with the assumptions of the concept of the interference ideal free distribution with costs) with distributions observed in laboratory experiments. The simulations were generated for two scenarios, where the shape of the functional response of fish is consistent with either type II or III. The results confirmed the hypothesis. The greatest similarity of the distributions obtained in the experiments and simulations was found for the simulations based on the scenario assuming the type III rather than type II for both age classes of Daphnia. This was consistent with the results of the experiments for the model parameterization, which revealed the type III functional response of fish. Therefore, the results suggest that aggregating may be maladaptive as an anti-vertebrate-predation defense in the case of zooplankton.
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Affiliation(s)
- Piotr Maszczyk
- Department of Hydrobiology, Faculty of Biology, University of Warsaw at Biology and Chemistry Research Centre, Żwirki i Wigury 101, Warsaw, Poland
| | - Ewa Babkiewicz
- Department of Hydrobiology, Faculty of Biology, University of Warsaw at Biology and Chemistry Research Centre, Żwirki i Wigury 101, Warsaw, Poland
| | - Marta Czarnocka-Cieciura
- Department of Hydrobiology, Faculty of Biology, University of Warsaw at Biology and Chemistry Research Centre, Żwirki i Wigury 101, Warsaw, Poland
| | - Z Maciej Gliwicz
- Department of Hydrobiology, Faculty of Biology, University of Warsaw at Biology and Chemistry Research Centre, Żwirki i Wigury 101, Warsaw, Poland
| | - Janusz Uchmański
- Faculty of Christian Philosophy, Institute of Ecology and Bioethics, Cardinal Stefan Wyszynski University, Wóycickiego 1/3, Warsaw, Poland
| | - Paulina Urban
- Laboratory of Functional and Structural Genomics, Center of New Technologies, University of Warsaw, Banacha 2c, Warsaw, Poland
- College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, Banacha 2c, Warsaw, Poland
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7
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Mehrparvar M, Zytynska SE, Balog A, Weisser WW. Coexistence through mutualist-dependent reversal of competitive hierarchies. Ecol Evol 2018; 8:1247-1259. [PMID: 29375795 PMCID: PMC5773332 DOI: 10.1002/ece3.3689] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 10/30/2017] [Accepted: 11/03/2017] [Indexed: 11/27/2022] Open
Abstract
Mechanisms that allow for the coexistence of two competing species that share a trophic level can be broadly divided into those that prevent competitive exclusion of one species within a local area, and those that allow for coexistence only at a regional level. While the presence of aphid‐tending ants can change the distribution of aphids among host plants, the role of mutualistic ants has not been fully explored to understand coexistence of multiple aphid species in a community. The tansy plant (Tanacetum vulgare) hosts three common and specialized aphid species, with only one being tended by ants. Often, these aphids species will not coexist on the same plant but will coexist across multiple plant hosts in a field. In this study, we aim to understand how interactions with mutualistic ants and predators affect the coexistence of multiple species of aphid herbivores on tansy. We show that the presence of ants drives community assembly at the level of individual plant, that is, the local community, by favoring one ant‐tended species, Metopeurum fuscoviride, while preying on the untended Macrosiphoniella tanacetaria and, to a lesser extent, Uroleucon tanaceti. Competitive hierarchies without ants were very different from those with ants. At the regional level, multiple tansy plants provide a habitat across which all aphid species can coexist at the larger spatial scale, while being competitively excluded at the local scale. In this case, ant mutualist‐dependent reversal of the competitive hierarchy can drive community dynamics in a plant–aphid system.
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Affiliation(s)
- Mohsen Mehrparvar
- Terrestrial Ecology Research Group Department of Ecology and Ecosystem Management Centre for Food and Life Sciences Weihenstephan Technical University of Munich Freising Germany.,Present address: Department of Biodiversity Institute of Science and High Technology and Environmental Sciences Graduate University of Advanced Technology Kerman Iran
| | - Sharon E Zytynska
- Terrestrial Ecology Research Group Department of Ecology and Ecosystem Management Centre for Food and Life Sciences Weihenstephan Technical University of Munich Freising Germany
| | - Adalbert Balog
- Department of Horticulture Faculty of Technical and Human Science Sapientia Hungarian University of Transylvania Tirgu-Mures Romania
| | - Wolfgang W Weisser
- Terrestrial Ecology Research Group Department of Ecology and Ecosystem Management Centre for Food and Life Sciences Weihenstephan Technical University of Munich Freising Germany
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8
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An empirical test of stable species coexistence in an amphipod species complex. Oecologia 2015; 178:819-31. [DOI: 10.1007/s00442-015-3262-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 02/02/2015] [Indexed: 11/26/2022]
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9
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Alric B, Jenny JP, Berthon V, Arnaud F, Pignol C, Reyss JL, Sabatier P, Perga ME. Local forcings affect lake zooplankton vulnerability and response to climate warming. Ecology 2013; 94:2767-80. [DOI: 10.1890/12-1903.1] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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10
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Tanaka Y, Mano H. Functional traits of herbivores and food chain efficiency in a simple aquatic community model. Ecol Modell 2012. [DOI: 10.1016/j.ecolmodel.2012.04.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Hanson N, Stark JD. A comparison of simple and complex population models to reduce uncertainty in ecological risk assessments of chemicals: example with three species of Daphnia. ECOTOXICOLOGY (LONDON, ENGLAND) 2011; 20:1268-1276. [PMID: 21503614 DOI: 10.1007/s10646-011-0675-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/07/2011] [Indexed: 05/30/2023]
Abstract
Ecological risk assessments (ERA) are mostly based on effects on survival (S) and fertility (F) of individuals. However, the protection goals are most often defined on the population or community levels. It has been argued that population models can be a useful link between the individual and the population in ERA. However, for population models to be efficiently and routinely used in ERA, the level of model complexity that is needed has to be clearly determined. In the present study, complex age classified matrix population models and simple 2-stage models were developed for three species of Daphnia. The population growth rate (λ) from the simple 2-stage model correlated strongly to the results of the complex matrix model, which included density dependence and temporary reductions in S and F. This shows that the information that can be provided by more complex models also can be relatively well predicted with the simpler model. The output of the complex matrix population models were also compared to the reductions in S that were used in the models. This was done because acute mortality is the most commonly used estimate of toxic effects. The results showed that λ from the 2-stage model correlated stronger to the endpoints of the matrix model than S did in all cases except for pulsed exposures, where S and λ correlated equally well.
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Affiliation(s)
- Niklas Hanson
- Puyallup Research and Extension Center, Washington State University, 2606 W Pioneer, Puyallup, WA 98371, USA.
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12
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Siepielski AM, McPeek MA. On the evidence for species coexistence: a critique of the coexistence program. Ecology 2010; 91:3153-64. [DOI: 10.1890/10-0154.1] [Citation(s) in RCA: 182] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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13
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Hülsmann S, Rinke K, Mooij WM. Size‐selective predation and predator‐induced life‐history shifts alter the outcome of competition between planktonic grazers. Funct Ecol 2010. [DOI: 10.1111/j.1365-2435.2010.01768.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Stephan Hülsmann
- Technische Universität Dresden, Institute of Hydrobiology, 01062 Dresden, and Technische Universität Dresden, Neunzehnhain Ecological Station, Neunzehnhainer Str. 14, 09514 Lengefeld, Germany
| | - Karsten Rinke
- Institute of Limnology, University of Konstanz, Mainaustr. 252, 78464 Konstanz, and UFZ, Brückstrasse 3a, D‐39114 Magdeburg, Germany
| | - Wolf M. Mooij
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO‐KNAW), Rijksstraatweg 6, 3631 AC Nieuwersluis, The Netherlands
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14
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Dakos V, Benincà E, van Nes EH, Philippart CJM, Scheffer M, Huisman J. Interannual variability in species composition explained as seasonally entrained chaos. Proc Biol Sci 2009; 276:2871-80. [PMID: 19474038 DOI: 10.1098/rspb.2009.0584] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The species composition of plankton, insect and annual plant communities may vary markedly from year to year. Such interannual variability is usually thought to be driven by year-to-year variation in weather conditions. Here we examine an alternative explanation. We studied the effects of regular seasonal forcing on a multi-species predator-prey model consisting of phytoplankton and zooplankton species. The model predicts that interannual variability in species composition can easily arise without interannual variability in external conditions. Seasonal forcing increased the probability of chaos in our model communities, but squeezed these irregular species dynamics within the seasonal cycle. As a result, the population dynamics had a peculiar character. Consistent with long-term time series of natural plankton communities, seasonal variation led to a distinct seasonal succession of species, yet the species composition varied from year to year in an irregular fashion. Our results suggest that interannual variability in species composition is an intrinsic property of multi-species communities in seasonal environments.
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Affiliation(s)
- Vasilis Dakos
- Department of Aquatic Ecology and Water Quality Management, Wageningen University, PO Box 47, 6700 AA Wageningen, The Netherlands
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