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Meziti A, Smeti E, Daniilides D, Spatharis S, Tsirtsis G, Kormas KA. Increased contribution of parasites in microbial eukaryotic communities of different Aegean Sea coastal systems. PeerJ 2023; 11:e16655. [PMID: 38144191 PMCID: PMC10740597 DOI: 10.7717/peerj.16655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 11/21/2023] [Indexed: 12/26/2023] Open
Abstract
Background-Aim Protistan communities have a major contribution to biochemical processes and food webs in coastal ecosystems. However, related studies are scarce and usually limited in specific groups and/or sites. The present study examined the spatial structure of the entire protistan community in seven different gulfs and three different depths in a regional Mediterranean Sea, aiming to define taxa that are important for differences detected in the marine microbial network across the different gulfs studied as well as their trophic interactions. Methods Protistan community structure analysis was based on the diversity of the V2-V3 hypervariable region of the 18S rRNA gene. Operational taxonomic units (OTUs) were identified using a 97% sequence identity threshold and were characterized based on their taxonomy, trophic role, abundance and niche specialization level. The differentially abundant, between gulfs, OTUs were considered for all depths and interactions amongst them were calculated, with statistic and network analysis. Results It was shown that Dinophyceae, Bacillariophyta and Syndiniales were the most abundant groups, prevalent in all sites and depths. Gulfs separation was more striking at surface corroborating with changes in environmental factors, while it was less pronounced in higher depths. The study of differentially abundant, between gulfs, OTUs revealed that the strongest biotic interactions in all depths occurred between parasite species (mainly Syndiniales) and other trophic groups. Most of these species were generalists but not abundant highlighting the importance of rare species in protistan community assemblage. Conclusion Overall this study revealed the emergence of parasites as important contributors in protistan network regulation regardless of depth.
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Affiliation(s)
- Alexandra Meziti
- Department of Marine Sciences, University of the Aegean, Mytilene, Greece
| | - Evangelia Smeti
- Department of Marine Sciences, University of the Aegean, Mytilene, Greece
- Institute of Marine Biological Resources & Inland Waters, Hellenic Centre for Marine Research, Anavissos, Greece
| | - Daniil Daniilides
- Faculty of Biology, Department of Ecology and Systematics, University of Athens, Athens, Greece
| | - Sofie Spatharis
- School of Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - George Tsirtsis
- Department of Marine Sciences, University of the Aegean, Mytilene, Greece
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2
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Christoforou E, Dominoni D, Lindström J, Diamantopoulou C, Czyzewski J, Mirzai N, Spatharis S. The effects of artificial light at night (ALAN) on the gaping activity and feeding of mussels. Mar Pollut Bull 2023; 192:115105. [PMID: 37290299 DOI: 10.1016/j.marpolbul.2023.115105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/21/2023] [Accepted: 05/25/2023] [Indexed: 06/10/2023]
Abstract
Artificial Light at Night (ALAN) is a common environmental pollutant which affects >22 % of the world's coastlines. However, the impact of ALAN wavelengths on coastal organisms is under-investigated. Here, we tested the impact of red, green, and white ALAN on the gaping activity and phytoplankton consumption of Mytilus edulis mussels and compared these to dark night. Mussels exhibited a semi-diel activity pattern. Although ALAN did not significantly affect the time open nor the phytoplankton consumption, it did have a colour-specific effect on the gaping frequency with red and white ALAN resulting in lower activity compared to the dark night. Green ALAN caused higher gaping frequency and a negative relationship between consumption and proportion of time open compared to the other treatments. Our findings suggest colour-specific ALAN effects on mussels and call for further investigation on the associated physiological mechanisms and potential ecological consequences.
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Affiliation(s)
- Eleni Christoforou
- University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, G12 8QQ Glasgow, UK; Cyprus University of Technology, Department of Chemical Engineering, 3036 Limassol, Cyprus.
| | - Davide Dominoni
- University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, G12 8QQ Glasgow, UK
| | - Jan Lindström
- University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, G12 8QQ Glasgow, UK
| | - Christina Diamantopoulou
- University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, G12 8QQ Glasgow, UK; University of Amsterdam, Institute for Biodiversity and Ecosystem Dynamics, 1098 XH Amsterdam, Netherlands
| | - Jakub Czyzewski
- University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, BioElectronics Unit, G12 8QQ Glasgow, UK
| | - Nosrat Mirzai
- University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, BioElectronics Unit, G12 8QQ Glasgow, UK
| | - Sofie Spatharis
- University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, G12 8QQ Glasgow, UK
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3
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Vad CF, Hanny-Endrédi A, Kratina P, Abonyi A, Mironova E, Murray DS, Samchyshyna L, Tsakalakis I, Smeti E, Spatharis S, Tan H, Preiler C, Petrusek A, Bengtsson MM, Ptacnik R. Spatial insurance against a heatwave differs between trophic levels in experimental aquatic communities. Glob Chang Biol 2023; 29:3054-3071. [PMID: 36946870 DOI: 10.1111/gcb.16692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 01/08/2023] [Accepted: 03/07/2023] [Indexed: 05/03/2023]
Abstract
Climate change-related heatwaves are major threats to biodiversity and ecosystem functioning. However, our current understanding of the mechanisms governing community resistance to and recovery from extreme temperature events is still rudimentary. The spatial insurance hypothesis postulates that diverse regional species pools can buffer ecosystem functioning against local disturbances through the immigration of better-adapted taxa. Yet, experimental evidence for such predictions from multi-trophic communities and pulse-type disturbances, like heatwaves, is largely missing. We performed an experimental mesocosm study to test whether species dispersal from natural lakes prior to a simulated heatwave could increase the resistance and recovery of plankton communities. As the buffering effect of dispersal may differ among trophic groups, we independently manipulated the dispersal of organisms from lower (phytoplankton) and higher (zooplankton) trophic levels. The experimental heatwave suppressed total community biomass by having a strong negative effect on zooplankton biomass, probably due to a heat-induced increase in metabolic costs, resulting in weaker top-down control on phytoplankton. While zooplankton dispersal did not alleviate the negative heatwave effects on zooplankton biomass, phytoplankton dispersal enhanced biomass recovery at the level of primary producers, providing partial evidence for spatial insurance. The differential responses to dispersal may be linked to the much larger regional species pool of phytoplankton than of zooplankton. Our results suggest high recovery capacity of community biomass independent of dispersal. However, community composition and trophic structure remained altered due to the heatwave, implying longer-lasting changes in ecosystem functioning.
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Affiliation(s)
- Csaba F Vad
- WasserCluster Lunz-Biologische Station, Lunz am See, Austria
- Institute of Aquatic Ecology, Centre for Ecological Research, Budapest, Hungary
- National Multidisciplinary Laboratory for Climate Change, Centre for Ecological Research, Budapest, Hungary
| | - Anett Hanny-Endrédi
- Institute of Aquatic Ecology, Centre for Ecological Research, Budapest, Hungary
| | - Pavel Kratina
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
| | - András Abonyi
- WasserCluster Lunz-Biologische Station, Lunz am See, Austria
- Institute of Aquatic Ecology, Centre for Ecological Research, Budapest, Hungary
| | - Ekaterina Mironova
- A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia
| | - David S Murray
- Collaborative Centre for Sustainable Use of the Seas (CCSUS), School of Biological Sciences, University of East Anglia, Norfolk, UK
- The Centre for Environmental, Fisheries and Aquaculture Science (Cefas), Suffolk, Lowestoft, UK
| | - Larysa Samchyshyna
- Institute of Fisheries, National Academy of Agrarian Sciences, Kyiv, Ukraine
- Institute of Fisheries and Marine Ecology, Berdiansk, Ukraine
| | - Ioannis Tsakalakis
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany
| | - Evangelia Smeti
- Institute of Marine Biological Resources and Inland Waters, Hellenic Centre for Marine Research, Anavissos, Greece
| | - Sofie Spatharis
- School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, Glasgow, UK
| | - Hanrong Tan
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
| | | | - Adam Petrusek
- Department of Ecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Mia M Bengtsson
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Robert Ptacnik
- WasserCluster Lunz-Biologische Station, Lunz am See, Austria
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4
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Diamantopoulou C, Christoforou E, Dominoni DM, Kaiserli E, Czyzewski J, Mirzai N, Spatharis S. Correction to: 'Wavelength-dependent effects of artificial light at night on phytoplankton growth and community structure' (2021) by Diamantopoulou et al. Proc Biol Sci 2022; 289:20221705. [PMID: 36382529 PMCID: PMC9667353 DOI: 10.1098/rspb.2022.1705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 10/24/2022] [Indexed: 11/15/2023] Open
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5
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Haddou Y, Mancy R, Matthiopoulos J, Spatharis S, Dominoni DM. Author Correction: Widespread extinction debts and colonization credits in United States breeding bird communities. Nat Ecol Evol 2022; 6:1788. [PMID: 36216907 PMCID: PMC9630109 DOI: 10.1038/s41559-022-01912-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Yacob Haddou
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Rebecca Mancy
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.,Social and Public Health Sciences Unit, University of Glasgow, Glasgow, UK
| | - Jason Matthiopoulos
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Sofie Spatharis
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.,School of Life Sciences, University of Glasgow, Glasgow, UK
| | - Davide M Dominoni
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.
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6
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Apostolopoulou NG, Smeti E, Lamorgese M, Varkitzi I, Whitfield P, Regnault C, Spatharis S. Microalgae show a range of responses to exometabolites of foreign species. ALGAL RES 2022; 62:None. [PMID: 35311224 PMCID: PMC8924005 DOI: 10.1016/j.algal.2021.102627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 10/14/2021] [Accepted: 12/23/2021] [Indexed: 12/01/2022]
Abstract
Studies on microalgae interspecific interactions have so far focused either on nutrient competition or allelopathic effects due to excreted substances from Harmful Algal Bloom (HAB) species. Evidence from plants, bacteria and specific microalgae groups, point to a range of responses mediated by sensing or direct chemical impact of exometabolites from foreign species. Such processes remain under-investigated, especially in non-HAB microalgae, despite the importance of such knowledge in ecology and industrial applications. Here, we study the directional effect of exometabolites of 4 "foreign" species Heterosigma akashiwo, Phaeocystis sp., Tetraselmis sp. and Thalassiosira sp. to each of three "target" species across a total of 12 treatments. We disentangle these effects from nutrient competition by adding cell free medium of each "foreign" species into our treatment cultures. We measured the biomass response, to the foreign exometabolites, as cell number and photosynthetic biomass (Chla), whereas nutrient use was measured as residual phosphorus (PO4) and intracellular phosphorus (P). Exometabolites from filtrate of foreign species were putatively annotated by untargeted metabolomics analysis and were discussed in association to observed responses of target species. Among others, these metabolites included L-histidinal, Tiliacorine and dimethylsulfoniopropionate (DMSP). Our findings show that species show a range of responses with the most common being biomass suppression, and less frequent biomass enhancement and intracellular P storage. Filtrate from the green microalgae Tetraselmis caused the most pronounced negative effects suggesting that non-HAB species can also cause negative chemical interference. A candidate metabolite inducing this response is L-histidinal which was measured in high abundance uniquely in Tetraselmis and its L-histidine form derived from bacteria was previously confirmed as a microalgal algicidal. H. akashiwo also induced biomass suppression on other microalgae and a candidate metabolite for this response is Tiliacorine, a plant-derived alkaloid with confirmed cytotoxic activity.
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Affiliation(s)
- Natalia G. Apostolopoulou
- Department of Ecology and Systematics, National and Kapodistrian University of Athens, 10679, Greece
- School of Life Sciences, University of Glasgow, G12 8QQ, UK
| | - Evangelia Smeti
- Institute of Marine Biological Resources and Inland Waters, HCMR Hellenic Centre for Marine Research, PO Box 713, Anavyssos 19013, Greece
| | | | - Ioanna Varkitzi
- Institute of Oceanography, HCMR Hellenic Centre for Marine Research, PO Box 713, Anavyssos 19013, Greece
| | | | | | - Sofie Spatharis
- School of Life Sciences, University of Glasgow, G12 8QQ, UK
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, G12 8QQ, UK
- Corresponding author at: School of Life Sciences, University of Glasgow, G12 8QQ, UK.
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7
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Baroja E, Christoforou E, Lindström J, Spatharis S. Effects of microplastics on bivalves: Are experimental settings reflecting conditions in the field? Mar Pollut Bull 2021; 171:112696. [PMID: 34252736 DOI: 10.1016/j.marpolbul.2021.112696] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Bivalves are the focus of experimental research as they can filtrate a broad size range of microplastics (MPs) with negative consequences for their physiology. Studies use a range of MP shapes, materials, sizes and concentrations raising the question on whether these reflect environmental observations. We review experimental studies on the effects of MPs on marine bivalves and contrast the MP characteristics used with corresponding data from the environment. Mussels were the most common bivalve across experiments which reflect their high abundance and broad distribution in the field. Although fibres are the dominant shape of MPs in coastal systems, most studies focus on spherules and beads, and MP concentrations are often orders of magnitude higher than environmental levels. For higher relevance of experimental findings we recommend that maximum experimental concentrations of MPs are in the range of 100-1000 particles/L, that there is more focus on microfibers and that concentration is reported in particles/volume.
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Affiliation(s)
- Estibaliz Baroja
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ Glasgow, UK
| | - Eleni Christoforou
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ Glasgow, UK; University of Glasgow, School of Life Sciences, G12 8QQ Glasgow, UK
| | - Jan Lindström
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ Glasgow, UK
| | - Sofie Spatharis
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ Glasgow, UK; University of Glasgow, School of Life Sciences, G12 8QQ Glasgow, UK.
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8
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Diamantopoulou C, Christoforou E, Dominoni DM, Kaiserli E, Czyzewski J, Mirzai N, Spatharis S. Wavelength-dependent effects of artificial light at night on phytoplankton growth and community structure. Proc Biol Sci 2021; 288:20210525. [PMID: 34157871 DOI: 10.1098/rspb.2021.0525] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Artificial light at night (ALAN) is a disruptive form of pollution, impacting physiological and behavioural processes that may scale up to population and community levels. Evidence from terrestrial habitats show that the severity and type of impact depend on the wavelength and intensity of ALAN; however, research on marine organisms is still limited. Here, we experimentally investigated the effect of different ALAN colours on marine primary producers. We tested the effect of green (525 nm), red (624 nm) and broad-spectrum white LED ALAN, compared to a dark control, on the green microalgae Tetraselmis suesica and a diatom assemblage. We show that green ALAN boosted chlorophyll production and abundance in T. suesica. All ALAN wavelengths affected assemblage biomass and diversity, with red and green ALAN having the strongest effects, leading to higher overall abundance and selective dominance of specific diatom species, some known to cause harmful algal blooms. Our findings show that green and red ALAN should be used with caution as alternative LED colours in coastal areas, where there might be a need to strike a balance between the effects of green and red light on marine primary producers with the benefit they appear to bring to other organisms.
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Affiliation(s)
- Christina Diamantopoulou
- Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece.,School of Life Sciences, University of Glasgow, Glasgow G128QQ, UK
| | - Eleni Christoforou
- School of Life Sciences, University of Glasgow, Glasgow G128QQ, UK.,Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G128QQ, UK
| | - Davide M Dominoni
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G128QQ, UK
| | - Eirini Kaiserli
- Molecular Cell and Systems Biology, University of Glasgow, Glasgow G128QQ, UK
| | - Jakub Czyzewski
- College of Medical, Veterinary and Life Sciences (MVLS), Bioelectronics Unit, University of Glasgow, Glasgow G128QQ, UK
| | - Nosrat Mirzai
- College of Medical, Veterinary and Life Sciences (MVLS), Bioelectronics Unit, University of Glasgow, Glasgow G128QQ, UK
| | - Sofie Spatharis
- School of Life Sciences, University of Glasgow, Glasgow G128QQ, UK.,Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G128QQ, UK
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9
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Christoforou E, Dominoni DM, Lindström J, Stilo G, Spatharis S. Effects of long-term exposure to microfibers on ecosystem services provided by coastal mussels. Environ Pollut 2020; 266:115184. [PMID: 32683089 DOI: 10.1016/j.envpol.2020.115184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/03/2020] [Accepted: 07/03/2020] [Indexed: 06/11/2023]
Abstract
The biofiltration capacity of bivalve populations is known to alleviate the effects of coastal eutrophication. However, this important ecosystem service could potentially be impaired by the increasing microplastic abundance in near shore environments. It is known that relatively large microplastics (∼500 μm) impair the filtration capacity of bivalves. However, the effect of smaller microplastics, and specifically microfibers, is not known even though they are more common in many natural systems and similar in size to phytoplankton, the main food source of mussels. Here, we investigated the effects of long-term exposure to microfibers (MFs), which are smaller than 100 μm, on the biofiltration capacity of the blue mussel, Mytilus edulis. Our findings show that long-term exposure (here 39 days) to microfibers significantly reduced (21%) the clearance of phytoplankton (Tetraselmis sp). While previous studies have shown that larger microplastics can decrease the filtration capacity of mussels after short-term exposure, our findings suggest that, for smaller MFs, mussel's clearance capacity is significantly affected after long-term exposure (39 days in this study). This may be due to the accumulation of MFs in the digestive system. In addition, the most efficient phytoplankton consumers were more susceptible to MF accumulation in the digestive system. This suggests that prolonged exposure to MF of coastal mussels could negatively impact the biofiltration of more potent individuals, thus decreasing the ecosystem service potential of the population as a whole.
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Affiliation(s)
- Eleni Christoforou
- University of Glasgow, School of Life Sciences, G12 8QQ, Glasgow, UK; University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ, Glasgow, UK.
| | - Davide M Dominoni
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ, Glasgow, UK
| | - Jan Lindström
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ, Glasgow, UK
| | - Giulia Stilo
- University of Glasgow, School of Life Sciences, G12 8QQ, Glasgow, UK; University of Turin, Department of Life Sciences and Systems Biology, 10154, Turin, Italy
| | - Sofie Spatharis
- University of Glasgow, School of Life Sciences, G12 8QQ, Glasgow, UK; University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, G12 8QQ, Glasgow, UK
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10
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Kafouris S, Smeti E, Spatharis S, Tsirtsis G, Economou-Amilli A, Danielidis DB. Nitrogen as the main driver of benthic diatom composition and diversity in oligotrophic coastal systems. Sci Total Environ 2019; 694:133773. [PMID: 31756832 DOI: 10.1016/j.scitotenv.2019.133773] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/17/2019] [Accepted: 08/03/2019] [Indexed: 06/10/2023]
Abstract
Phytoplankton is the main indicator group for eutrophication in coastal ecosystems, however its high dispersal potential does not enable the assessment of localized effects of coastal nutrient enrichment. Benthic diatoms are sessile microalgae associated with sandy substrates and have the potential to reflect more localized pollution impacts. Although benthic diatoms are widely used bioindicators in freshwater systems, they have rarely been used for assessing the eutrophication status of oligotrophic environments such as the eastern Mediterranean Sea. In the present study, we assess the efficiency of benthic diatoms as bioindicators of nutrient enrichment in oligotrophic coastal systems, by investigating the effect of different physicochemical conditions and nutrient concentrations on the assemblage composition, diversity and individual species populations. To do this, we sampled along a eutrophication gradient formed by anthropogenic nutrient inputs from a metropolitan area. The main driver of assemblage composition, diversity and biomass of diatoms was nitrogen concentration and its temporal and spatial changes. Nitrogen loadings were positively correlated with increased biomass of Cocconeis spp. and negatively correlated with Mastogloia spp. Our findings suggest that in coastal ecosystems of oligotrophic marine ecoregions, benthic diatom assemblage structure and specific taxonomic groups can be reliable predictors of coastal eutrophication offering higher spatial resolution compared to phytoplankton.
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Affiliation(s)
- Savvas Kafouris
- University of Athens, Faculty of Biology, Department of Ecology and Systematics, Panepistimiopolis, Athens 15784, Greece; Department of Fisheries and Marine Research, 1416 Nicosia, Cyprus
| | - Evangelia Smeti
- Hellenic Centre for Marine Research, Institute of Marine Biological Resources & Inland Waters, 46.7 km Athens-Souniou Av., 19013, Anavissos, Attica, Greece
| | - Sofie Spatharis
- University of Glasgow, School of Life Sciences, Glasgow G12 8QQ, Scotland, UK; University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, Glasgow G12 8QQ, Scotland, UK.
| | - George Tsirtsis
- University of the Aegean, Department of Marine Sciences, University Hill, 81100 Mytilene, Greece
| | - Athena Economou-Amilli
- University of Athens, Faculty of Biology, Department of Ecology and Systematics, Panepistimiopolis, Athens 15784, Greece
| | - Daniel B Danielidis
- University of Athens, Faculty of Biology, Department of Ecology and Systematics, Panepistimiopolis, Athens 15784, Greece
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11
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Spatharis S, Lamprinou V, Meziti A, Kormas KA, Danielidis DD, Smeti E, Roelke DL, Mancy R, Tsirtsis G. Everything is not everywhere: can marine compartments shape phytoplankton assemblages? Proc Biol Sci 2019; 286:20191890. [PMID: 31662088 DOI: 10.1098/rspb.2019.1890] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The idea that 'everything is everywhere, but the environment selects' has been seminal in microbial biogeography, and marine phytoplankton is one of the prototypical groups used to illustrate this. The typical argument has been that phytoplankton is ubiquitous, but that distinct assemblages form under environmental selection. It is well established that phytoplankton assemblages vary considerably between coastal ecosystems. However, the relative roles of compartmentalization of regional seas and site-specific environmental conditions in shaping assemblage structures have not been specifically examined. We collected data from coastal embayments that fall within two different water compartments within the same regional sea and are characterized by highly localized environmental pressures. We used principal coordinates of neighbour matrices (PCNM) and asymmetric eigenvector maps (AEM) models to partition the effects that spatial structures, environmental conditions and their overlap had on the variation in assemblage composition. Our models explained a high percentage of variation in assemblage composition (59-65%) and showed that spatial structure consistent with marine compartmentalization played a more important role than local environmental conditions. At least during the study period, surface currents connecting sites within the two compartments failed to generate sufficient dispersal to offset the impact of differences due to compartmentalization. In other words, our findings suggest that, even for a prototypical cosmopolitan group, everything is not everywhere.
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Affiliation(s)
- Sofie Spatharis
- School of Life Sciences, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK.,Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK
| | - Vasiliki Lamprinou
- Faculty of Biology, Department of Ecology and Systematics, University of Athens, Panepistimiopolis, Athens 15784, Greece
| | - Alexandra Meziti
- Department of Ichthyology and Aquatic Environment, University of Thessaly, 3844 46 Volos, Greece
| | - Konstantinos A Kormas
- Department of Ichthyology and Aquatic Environment, University of Thessaly, 3844 46 Volos, Greece
| | - Daniel D Danielidis
- Faculty of Biology, Department of Ecology and Systematics, University of Athens, Panepistimiopolis, Athens 15784, Greece
| | - Evangelia Smeti
- Hellenic Centre for Marine Research, Institute of Marine Biological Resources and Inland Waters, 46.7 km Athens-Souniou Avenue, 19013 Anavissos, Attica, Greece
| | - Daniel L Roelke
- Department of Marine Biology, Texas A&M University at Galveston, 200 Seawolf Parkway, Galveston, TX 77554, USA
| | - Rebecca Mancy
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK
| | - George Tsirtsis
- Department of Marine Sciences, University of the Aegean, University Hill, 81100 Mytilene, Greece
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12
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Cáceres C, Spatharis S, Kaiserli E, Smeti E, Flowers H, Bonachela JA. Temporal phosphate gradients reveal diverse acclimation responses in phytoplankton phosphate uptake. ISME J 2019; 13:2834-2845. [PMID: 31350454 DOI: 10.1038/s41396-019-0473-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 06/11/2019] [Accepted: 06/28/2019] [Indexed: 11/10/2022]
Abstract
Phytoplankton face environmental nutrient variations that occur in the dynamic upper layers of the ocean. Phytoplankton cells are able to rapidly acclimate to nutrient fluctuations by adjusting their nutrient-uptake system and metabolism. Disentangling these acclimation responses is a critical step in bridging the gap between phytoplankton cellular physiology and community ecology. Here, we analyzed the dynamics of phosphate (P) uptake acclimation responses along different P temporal gradients by using batch cultures of the diatom Phaeodactylum tricornutum. We employed a multidisciplinary approach that combined nutrient-uptake bioassays, transcriptomic analysis, and mathematical models. Our results indicated that cells increase their maximum nutrient-uptake rate (Vmax) both in response to P pulses and strong phosphorus limitation. The upregulation of three genes coding for different P transporters in cells experiencing low intracellular phosphorus levels supported some of the observed Vmax variations. In addition, our mathematical model reproduced the empirical Vmax patterns by including two types of P transporters upregulated at medium-high environmental and low intracellular phosphorus levels, respectively. Our results highlight the existence of a sequence of acclimation stages along the phosphate continuum that can be understood as a succession of acclimation responses. We provide a novel conceptual framework that can contribute to integrating and understanding the dynamics and wide diversity of acclimation responses developed by phytoplankton.
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Affiliation(s)
- Carlos Cáceres
- Department of Mathematics and Statistics, University of Strathclyde, Livingstone Tower, 26 Richmond St., Glasgow, Scotland, G1 1XH, UK. .,Schiermeier Olentangy River Wetland Research Park, School of Environment and Natural Resources, The Ohio State University, Columbus, OH, 43202, USA.
| | - Sofie Spatharis
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland, G12 8QQ, UK.,School of Life Sciences, University of Glasgow, Glasgow, Scotland, G12 8QQ, UK
| | - Eirini Kaiserli
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Evangelia Smeti
- Hellenic Centre for Marine Research, Institute of Marine Biological Resources and Inland Waters, 46.7 km Athens-Sounio Ave., Anavyssos, 19013, Greece
| | - Hugh Flowers
- Department of Chemistry, University of Glasgow, Glasgow, Scotland, G12 8QQ, UK
| | - Juan A Bonachela
- Department of Mathematics and Statistics, University of Strathclyde, Livingstone Tower, 26 Richmond St., Glasgow, Scotland, G1 1XH, UK. .,Department of Ecology, Evolution, and Natural Resources, Rutgers University, 14 College Farm Road, New Brunswick, NJ, 08901, USA.
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Peters L, Spatharis S, Dario MA, Dwyer T, Roca IJT, Kintner A, Kanstad-Hanssen Ø, Llewellyn MS, Praebel K. Environmental DNA: A New Low-Cost Monitoring Tool for Pathogens in Salmonid Aquaculture. Front Microbiol 2018; 9:3009. [PMID: 30581425 PMCID: PMC6292926 DOI: 10.3389/fmicb.2018.03009] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 11/20/2018] [Indexed: 01/17/2023] Open
Abstract
Environmental DNA (eDNA) metabarcoding is a relatively new monitoring tool featuring in an increasing number of applications such as the facilitation of the accurate and cost effective detection of species in environmental samples. eDNA monitoring is likely to have a major impact on the ability of salmonid aquaculture industry producers and their regulators to detect the presence and abundance of pathogens and other biological threats in the surrounding environment. However, for eDNA metabarcoding to develop into a useful bio-monitoring tool it is necessary to (a) validate that sequence datasets derived from amplification of metabarcoding markers reflect the true species' identity, (b) test the sensitivity under different abundance levels and environmental noise and (c) establish a low-cost sequencing method to enable the bulk processing of field samples. In this study, we employed an elaborate experimental design whereby different combinations of five biological agents were crossed at three abundance levels and exposed to sterile pre-filtered and unfiltered seawater, prior to coarse filtering and then eDNA ultrafiltration of the resultant material. We then benchmarked the low-cost, scalable, Ion Torrent sequencing method against the current gold-standard Illumina platform for eDNA surveys in aquaculture. Based on amplicon-seq of the 18S SSU rDNA v9 region, we were able to identify two parasites (Lepeophtheirus salmonis and Paramoeba perurans) to species level, whereas the microalgae species Prymnesium parvum, Pseudo-nitzschia seriata, and P. delicatissima could be assigned correctly only to the genus level. Illumina and Ion Torrent provided near identical results in terms of community composition in our samples, whereas Ion Torrent was more sensitive in detecting species richness when the medium was unfiltered seawater. Both methods were able to reflect the difference in relative abundance between treatments in 4 out of 5 species when samples were exposed to the unfiltered seawater, despite the significant amount of background noise from both bacteria and eukaryotes. Our findings indicate that eDNA metabarcoding offers significant potential in the monitoring of species harmful to aquaculture and for this purpose, the low-cost Ion Torrent sequencing is as accurate as Illumina in determining differences in their relative abundance between samples.
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Affiliation(s)
- Lucy Peters
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Sofie Spatharis
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
- School of Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Maria Augusta Dario
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz (IOC/Fiocruz), Rio de Janeiro, Brazil
| | - Toni Dwyer
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Inaki J. T. Roca
- Norwegian College of Fishery Science, University of Tromsø, Tromsø, Norway
| | - Anna Kintner
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | | | - Martin S. Llewellyn
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Kim Praebel
- Norwegian College of Fishery Science, University of Tromsø, Tromsø, Norway
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Smeti E, Roelke DL, Tsirtsis G, Spatharis S. Species extinctions strengthen the relationship between biodiversity and resource use efficiency. Ecol Modell 2018. [DOI: 10.1016/j.ecolmodel.2018.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Tamvakis A, Anagnostopoulos CN, Tsirtsis G, Niros AD, Spatharis S. Optimized Classification Predictions with a New Index Combining Machine Learning Algorithms. INT J ARTIF INTELL T 2018. [DOI: 10.1142/s0218213018500124] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Voting is a commonly used ensemble method aiming to optimize classification predictions by combining results from individual base classifiers. However, the selection of appropriate classifiers to participate in voting algorithm is currently an open issue. In this study we developed a novel Dissimilarity-Performance (DP) index which incorporates two important criteria for the selection of base classifiers to participate in voting: their differential response in classification (dissimilarity) when combined in triads and their individual performance. To develop this empirical index we firstly used a range of different datasets to evaluate the relationship between voting results and measures of dissimilarity among classifiers of different types (rules, trees, lazy classifiers, functions and Bayes). Secondly, we computed the combined effect on voting performance of classifiers with different individual performance and/or diverse results in the voting performance. Our DP index was able to rank the classifier combinations according to their voting performance and thus to suggest the optimal combination. The proposed index is recommended for individual machine learning users as a preliminary tool to identify which classifiers to combine in order to achieve more accurate classification predictions avoiding computer intensive and time-consuming search.
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Affiliation(s)
- Androniki Tamvakis
- Department of Marine Sciences, University of the Aegean, University Hill, Mytilene, 81100, Greece
| | | | - George Tsirtsis
- Department of Marine Sciences, University of the Aegean, University Hill, Mytilene, 81100, Greece
| | - Antonios D. Niros
- Department of Cultural Technology and Communication, University of the Aegean, University Hill, Mytilene, 81100, Greece
| | - Sofie Spatharis
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland, G12 8QQ, UK
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Abstract
The effect of life-history traits on resource competition outcomes is well understood in the context of a constant resource supply. However, almost all natural systems are subject to fluctuations of resources driven by cyclical processes such as seasonality and tidal hydrology. To understand community composition, it is therefore imperative to study the impact of resource fluctuations on interspecies competition. We adapted a well-established resource-competition model to show that fluctuations in inflow concentrations of two limiting resources lead to the survival of species in clumps along the trait axis, consistent with observations of "lumpy coexistence" [Scheffer M, van Nes EH (2006) Proc Natl Acad Sci USA 103:6230-6235]. A complex dynamic pattern in the available ambient resources arose very early in the self-organization process and dictated the locations of clumps along the trait axis by creating niches that promoted the growth of species with specific traits. This dynamic pattern emerged as the combined result of fluctuations in the inflow of resources and their consumption by the most competitive species that accumulated the bulk of biomass early in assemblage organization. Clumps emerged robustly across a range of periodicities, phase differences, and amplitudes. Given the ubiquity in the real world of asynchronous fluctuations of limiting resources, our findings imply that assemblage organization in clumps should be a common feature in nature.
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Affiliation(s)
- Athanasia Sakavara
- Department of the Environment, University of the Aegean, Mytilene 81100, Greece
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - George Tsirtsis
- Department of Marine Sciences, University of the Aegean, Mytilene 81100, Greece
| | - Daniel L Roelke
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX 77843-2258
- Department of Oceanography, Texas A&M University, College Station, TX 77843-2258
| | - Rebecca Mancy
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Sofie Spatharis
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom;
- School of Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
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Karayanni H, Meziti A, Spatharis S, Genitsaris S, Courties C, Kormas KA. Changes in Microbial (Bacteria and Archaea) Plankton Community Structure after Artificial Dispersal in Grazer-Free Microcosms. Microorganisms 2017; 5:microorganisms5020031. [PMID: 28587211 PMCID: PMC5488102 DOI: 10.3390/microorganisms5020031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 05/16/2017] [Accepted: 05/30/2017] [Indexed: 11/16/2022] Open
Abstract
Microbes are considered to have a global distribution due to their high dispersal capabilities. However, our knowledge of the way geographically distant microbial communities assemble after dispersal in a new environment is limited. In this study, we examined whether communities would converge because similar taxa would be selected under the same environmental conditions, or would diverge because of initial community composition, after artificial dispersal. To this aim, a microcosm experiment was performed, in which the temporal changes in the composition and diversity of different prokaryoplankton assemblages from three distant geographic coastal areas (Banyuls-sur-Mer in northwest Mediterranean Sea, Pagasitikos Gulf in northeast Mediterranean and Woods Hole, MA, USA in the northwest Atlantic), were studied. Diversity was investigated using amplicon pyrosequencing of the V1–V3 hypervariable regions of the 16S rRNA. The three assemblages were grown separately in particle free and autoclaved Banyuls-sur-mer seawater at 18 °C in the dark. We found that the variability of prokaryoplankton community diversity (expressed as richness, evenness and dominance) as well as the composition were driven by patterns observed in Bacteria. Regarding community composition, similarities were found between treatments at family level. However, at the OTU level microbial communities from the three different original locations diverge rather than converge during incubation. It is suggested that slight differences in the composition of the initial prokaryoplankton communities, resulted in separate clusters the following days even when growth took place under identical abiotic conditions.
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Affiliation(s)
- Hera Karayanni
- Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece.
| | - Alexandra Meziti
- Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece.
| | - Sofie Spatharis
- University of Glasgow, BAHCM Institute and School of Life Sciences, Glasgow G12 8QQ, Scotland, UK.
| | - Savvas Genitsaris
- Laboratoire d'Océanologie et Géosciences (LOG), UMR CNRS 8187, Université du Littoral Côte d'Opale (ULCO), 32 av. Foch, 62930 Wimereux, France.
| | - Claude Courties
- Sorbonne Universités, UPMC Univ Paris 06, UMS2348, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique, 66650 Banyuls-sur-mer, France.
| | - Konstantinos A Kormas
- Department of Ichthyology & Aquatic Environment, University of Thessaly, 383 46 Volos, Greece.
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Affiliation(s)
- Evangelia Smeti
- Dept of Marine Sciences; Univ. of the Aegean, University Hill; GR-81100 Mytilene Greece
| | - Daniel L. Roelke
- Dept of Wildlife and Fisheries Sciences; Texas A&M University; 2258 TAMUS College Station TX 77843-2258 USA
| | - Sofie Spatharis
- Inst. of Biodiversity, Animal Health and Comparative Medicine, Univ. of Glasgow; Glasgow G12 8QQ Scotland UK
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Abstract
Coastal marine systems are affected by seasonal variations in biogeochemical and physical processes, sometimes leading to alternating periods of reproductive growth limitation within an annual cycle. Transitions between these periods can be sudden or gradual. Human activities, such as reservoir construction and interbasin water transfers, influence these processes and can affect the type of transition between resource loading conditions. How such human activities might influence phytoplankton succession is largely unknown. Here, we employ a multispecies, multi-nutrient model to explore how nutrient loading switching mode might affect phytoplankton succession. The model is based on the Monod-relationship, predicting an instantaneous reproductive growth rate from ambient inorganic nutrient concentrations whereas the limiting nutrient at any given time was determined by Liebig's Law of the Minimum. When these relationships are combined with population loss factors, such as hydraulic displacement of cells associated with inflows, a characterization of a species' niche can be achieved through application of the R* conceptual model, thus enabling an ecological interpretation of modeling results. We found that the mode of reversal in resource supply concentrations had a profound effect. When resource supply reversals were sudden, as expected in systems influenced by pulsed inflows or wind-driven mixing events, phytoplankton were characterized by alternating succession dynamics, a phenomenon documented in inland water bodies of temperate latitudes. When resource supply reversals were gradual, as expected in systems influenced by seasonally developing wet and dry seasons, or annually occurring periods of upwelling, phytoplankton dynamics were characterized by mirror-image succession patterns. This phenomenon has not been reported previously in plankton systems but has been observed in some terrestrial plant systems. These findings suggest that a transition from alternating to "mirror-image" succession patterns might arise with continued coastal zone development, with crucial implications for ecosystems dependent on time-sensitive processes, e.g., spawning events and migration patterns.
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Affiliation(s)
- Daniel L. Roelke
- Texas A&M University, Department of Wildlife and Fisheries Sciences, and Department of Oceanography, 2258 TAMUS, College Station, Texas, United States of America
| | - Sofie Spatharis
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, Glasgow, Scotland, United Kingdom
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20
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Abstract
Annual variations in biogeochemical and physical processes can lead to nutrient variability and seasonal patterns in phytoplankton productivity and assemblage structure. In many coastal systems river inflow and water exchange with the ocean varies seasonally, and alternating periods can arise where the nutrient most limiting to phytoplankton growth switches. Transitions between these alternating periods can be sudden or gradual and this depends on human activities, such as reservoir construction and interbasin water transfers. How such activities might influence phytoplankton assemblages is largely unknown. Here, we employed a multispecies, multi-nutrient model to explore how nutrient loading switching mode might affect characteristics of phytoplankton assemblages. The model is based on the Monod-relationship, predicting an instantaneous growth rate from ambient inorganic nutrient concentrations whereas the limiting nutrient at any given time was determined by Liebig's Law of the Minimum. Our simulated phytoplankton assemblages self-organized from species rich pools over a 15-year period, and only the surviving species were considered as assemblage members. Using the model, we explored the interactive effects of complementarity level in trait trade-offs within phytoplankton assemblages and the amount of noise in the resource supply concentrations. We found that the effect of shift from a sudden resource supply transition to a gradual one, as observed in systems impacted by watershed development, was dependent on the level of complementarity. In the extremes, phytoplankton species richness and relative overyielding increased when complementarity was lowest, and phytoplankton biomass increased greatly when complementarity was highest. For low-complementarity simulations, the persistence of poorer-performing phytoplankton species of intermediate R*s led to higher richness and relative overyielding. For high-complementarity simulations, the formation of phytoplankton species clusters and niche compression enabled higher biomass accumulation. Our findings suggest that an understanding of factors influencing the emergence of life history traits important to complementarity is necessary to predict the impact of watershed development on phytoplankton productivity and assemblage structure.
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Affiliation(s)
- Daniel L. Roelke
- Texas A&M University, Department of Wildlife and Fisheries Sciences, and Department of Oceanography, 2258 TAMUS, College Station, Texas 77843–2258, United States of America
| | - Sofie Spatharis
- University of Glasgow, Institute of Biodiversity, Animal Health and Comparative Medicine, Glasgow, G12 8QQ, Scotland, United Kingdom
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Carteron A, Jeanmougin M, Leprieur F, Spatharis S. Assessing the efficiency of clustering algorithms and goodness-of-fit measures using phytoplankton field data. ECOL INFORM 2012. [DOI: 10.1016/j.ecoinf.2012.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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