1
|
Kang J, Liu X, Lin X, Chen X, Luo Z, Huang B. Biogeochemical factors regulating photosynthetically dissolved organic carbon produced by phytoplankton in the Taiwan Strait. ENVIRONMENTAL RESEARCH 2024; 252:119090. [PMID: 38719063 DOI: 10.1016/j.envres.2024.119090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 05/01/2024] [Accepted: 05/06/2024] [Indexed: 05/13/2024]
Abstract
The distribution and mechanisms of photosynthetically dissolved organic carbon (PDOC) released by marine phytoplankton are frequently neglected and inadequately understood because most studies on carbon sequestration capacity have focused on photosynthetic particulate organic carbon. In this study, percentage extracellular release (PER) and its environmental influencing factors were investigated for 10 cruises in the Taiwan Strait during 2006-2023. The results indicated that the PER increased horizontally from the nearshore to the off-shelf and vertically from the surface to the bottom within the euphotic zone. PER tends to be low in eutrophic waters such as upwellings and estuaries and high in oligotrophic waters. The study revealed that the average contribution of PDOC to total primary productivity (TPP) in the Taiwan Strait could reach 18.2 ± 11.7%, which is similar to the previously estimated global oceanic values. PDOC production satisfied approximately 25% the carbon requirements of heterotropic bacteria (HB). A detailed analysis of the PER combined with model simulations proved that the distribution of the PER in the Taiwan Strait was caused by the joint contribution of irradiance, size-fractionated phytoplankton, and nutrient stoichiometry. Our results contradict the view that the PER is a constant factor that is unaffected by TPP. However, there was a significant negative correlation between the PER and TPP. The PDOC was always lower than the bacterial carbon demand for a broad range of bacterial growth efficiencies, suggesting a weak coupling between phytoplankton exudation and bacterial metabolism. This challenges the idea that there is a well-coupled relationship between bacteria and phytoplankton present on the continental shelf. These findings indicate significant discrepancies in PDOC mechanisms and the quantitative importance of nearshore eutrophic and off-shelf oligotrophic environments. Consequently, it is unwise to use uniform PERs without differentiation under trophic conditions when reevaluating and appraising marine carbon fixation.
Collapse
Affiliation(s)
- Jianhua Kang
- College of Oceanography, Hohai University, Nanjing, 210024, PR China; Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, PR China; College of Marine Living Resource Sciences and Management, Shanghai Ocean University, Shanghai, 201306, PR China; Observation and Research Station of Island and Coastal Ecosystem in the Western Taiwan Straits, Ministry of Natural Resources, Xiamen, 361005, PR China
| | - Xuancheng Liu
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, PR China; College of Marine Living Resource Sciences and Management, Shanghai Ocean University, Shanghai, 201306, PR China
| | - Xiangyuan Lin
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, PR China; Observation and Research Station of Island and Coastal Ecosystem in the Western Taiwan Straits, Ministry of Natural Resources, Xiamen, 361005, PR China
| | - Xianwu Chen
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, PR China; Observation and Research Station of Island and Coastal Ecosystem in the Western Taiwan Straits, Ministry of Natural Resources, Xiamen, 361005, PR China
| | - Zhaohe Luo
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, PR China; Observation and Research Station of Island and Coastal Ecosystem in the Western Taiwan Straits, Ministry of Natural Resources, Xiamen, 361005, PR China.
| | - Bangqin Huang
- College of Oceanography, Hohai University, Nanjing, 210024, PR China; Fujian Provincial Key Laboratory of Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, Xiamen, 361005, PR China; National Observation and Research Station for the Taiwan Strait Marine Ecosystem, Xiamen, 361005, PR China.
| |
Collapse
|
2
|
Carrillo P, González-Olalla JM, J Cabrerizo M, Villar-Argaiz M, Medina-Sánchez JM. Uneven response of phytoplankton-bacteria coupling under Saharan dust pulse and ultraviolet radiation in the south-western Mediterranean Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172220. [PMID: 38588733 DOI: 10.1016/j.scitotenv.2024.172220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/21/2024] [Accepted: 04/02/2024] [Indexed: 04/10/2024]
Abstract
The microbial carbon (C) flux in the ocean is a key functional process governed by the excretion of organic carbon by phytoplankton (EOC) and heterotrophic bacterial carbon demand (BCD). Ultraviolet radiation (UVR) levels in upper mixed layers and increasing atmospheric dust deposition from arid regions may alter the degree of coupling in the phytoplankton-bacteria relationship (measured as BCD:EOC ratio) with consequences for the C-flux through these compartments in marine oligotrophic ecosystem. Firstly, we performed a field study across the south-western (SW) Mediterranean Sea to assess the degree of coupling (BCD:EOC) and how it may be related to metabolic balance (total primary production: community respiration; PPT:CR). Secondly, we conducted a microcosm experiment in two contrasting areas (heterotrophic nearshore and autotrophic open sea) to test the impact of UVR and dust interaction on microbial C flux. In the field study, we found that BCD was not satisfied by EOC (i.e., BCD:EOC >1; uncoupled phytoplankton-bacteria relationship). BCD:EOC ratio was negatively related to PPT:CR ratio across the SW Mediterranean Sea. A spatial pattern emerged, i.e. in autotrophic open sea stations uncoupling was less severe (BCD:EOC ranged 1-2), whereas heterotrophic nearshore stations uncoupling was more severe (BCD:EOC > 2). In the experimental study, in the seawater both enriched with dust and under UVR, BCD:EOC ratio decreased by stimulating autotrophic processes (particulate primary production (PPP) and EOC) in the heterotrophic nearshore area, whereas BCD:EOC increased by stimulating heterotrophic processes [heterotrophic bacterial production (HBP), bacterial growth efficiency (BGE), bacterial respiration (BR)] in the autotrophic open sea. Our results show that this spatial pattern could be reversed under future UVR × Dust scenario. Overall, the impact of greater dust deposition and higher UVR levels will alter the phytoplankton-bacteria C-flux with consequences for the productivity of both communities, their standing stocks, and ultimately, the ecosystem's metabolic balance at the sea surface.
Collapse
Affiliation(s)
- Presentación Carrillo
- Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, nº4, 18071, Granada, Spain.
| | - Juan Manuel González-Olalla
- Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, nº4, 18071, Granada, Spain.
| | - Marco J Cabrerizo
- Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, nº4, 18071, Granada, Spain; Departamento de Ecología, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| | - Manuel Villar-Argaiz
- Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, nº4, 18071, Granada, Spain; Departamento de Ecología, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| | - Juan Manuel Medina-Sánchez
- Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, nº4, 18071, Granada, Spain; Departamento de Ecología, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| |
Collapse
|
3
|
Lozano IL, González-Olalla JM, Medina-Sánchez JM. New Insights for the Renewed Phytoplankton-Bacteria Coupling Concept: the Role of the Trophic Web. MICROBIAL ECOLOGY 2023; 86:810-824. [PMID: 36574041 DOI: 10.1007/s00248-022-02159-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 12/08/2022] [Indexed: 07/12/2023]
Abstract
It is widely accepted that in many aquatic ecosystems bacterioplankton is dependent on and regulated by organic carbon supplied by phytoplankton, leading to coupled algae-bacteria relationship. In this study, an in-depth analysis of this relationship has been carried out by combining two approaches: (i) a correlation analyses between heterotrophic bacterial production (BP) vs. primary production (PP) or algal excretion of organic carbon (EOC), (ii) the balance between bacterial carbon demands (BCD) and the supply of C as EOC, measured as BCD:EOC ratio. During the study period (2013-2016), the algae-bacteria relationship was constantly changing from a coupling in 2013, uncoupling in 2014 and 2015, and an incipient return to coupling (in 2016). Our results show that top-down control (bacterivory) by algal mixotrophy acts as a decoupling force since it provides a fresh C source different to algal EOC to satisfy bacterial carbon demands. Notably, a relationship between the BCD:EOC ratio and the ecosystem metabolic balance (Primary production (PP): respiration (R)) was found, suggesting that PP:R may be a good predictor of the algae-bacteria coupling. This analysis, including the comparison between basal and potential ecosystem metabolic balance, can be a tool to improve knowledge on the interaction between both biotics compartments, which the traditional analyses on coupling may not capture.
Collapse
Affiliation(s)
- I L Lozano
- Department of Forest Sciences, University of Helsinki, 00014, Helsinki, Finland
- Institute for Atmospheric and Earth System Research, University of Helsinki, 00014, Helsinki, Finland
| | - J M González-Olalla
- Department of Watershed Sciences, Utah State University, Utah, 84322, USA.
- University Institute of Water Research, University of Granada, 18071, Granada, Spain.
| | - J M Medina-Sánchez
- University Institute of Water Research, University of Granada, 18071, Granada, Spain
- Department of Ecology, Faculty of Sciences, University of Granada, 18071, Granada, Spain
| |
Collapse
|
4
|
Conan P, Philip L, Ortega-Retuerta E, Odobel C, Duran C, Pandin C, Giraud C, Meistertzheim AL, Barbe V, Ter Hall A, Pujo-Pay M, Ghiglione JF. Evidence of coupled autotrophy and heterotrophy on plastic biofilms and its influence on surrounding seawater. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 315:120463. [PMID: 36272613 DOI: 10.1016/j.envpol.2022.120463] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/22/2022] [Accepted: 10/15/2022] [Indexed: 06/16/2023]
Abstract
We measured phytoplankton primary production and heterotrophic bacterial activities on microplastics and seawater in the Northwestern Mediterranean Sea during two 3-month spring periods over 2 consecutive years. Microorganisms growing on a 5 mm diameter low density polyethylene films (LDPE; 200 μm thick) faced two contrasting conditions depending on the year. Spring 2018 was characterized by consistent nutrient inputs and bloom development. In spring 2019, nutrient inputs and bloom were low. For the first time, we observed a clear coupling between primary production and heterotrophic prokaryote production on microplastics during both years, but with different intensity between years that reflected the crucial role of the trophic environmental conditions (nutrient supply) in shaping microbial activities on plastics. We found that high primary production on plastics could support the whole (net autotrophy) or the majority of the bacterial carbon demand needed for heterotrophic activities, supplemented by other carbon sources if surrounding waters are highly productive. We propose that microbial activity on plastics influences the microbial community in the surrounding seawater, especially when the environmental conditions are less favorable. An illustrative image of the role of plastics in the environment could be that of an inverter in an electrical circuit that mitigates both positive and negative variations. Our results highlight the potential role of the plastisphere in shaping biogeochemical cycles in the context of increasing amounts of plastic particles in the marine environment.
Collapse
Affiliation(s)
- Pascal Conan
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France; Sorbonne Université, CNRS OSU STAMAR - UAR2017, 4 Place Jussieu, 75252, Paris cedex 05, France.
| | - Léna Philip
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France; SAS Plastic@Sea, Sorbonne Université (UPMC), CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| | - Eva Ortega-Retuerta
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| | - Charlène Odobel
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| | - Clélia Duran
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| | - Caroline Pandin
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| | - Carolane Giraud
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France; CNRS, UMR 9220 ENTROPIE, Ifremer (LEAD-NC), IRD, Univ Nouvelle-Calédonie, Univ La Réunion, Nouméa, New Caledonia
| | - Anne-Leila Meistertzheim
- SAS Plastic@Sea, Sorbonne Université (UPMC), CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| | - Valérie Barbe
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91057, Evry, France
| | - Alexandra Ter Hall
- CNRS, Université de Toulouse, Laboratoire des Interactions Moléculaires et Réactivité Chimique et Photochimique (IMRCP), UMR, 5623, Toulouse, France
| | - Mireille Pujo-Pay
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| | - Jean-François Ghiglione
- Sorbonne Université, CNRS LOMIC - UMR 7621, Laboratoire d'Océanographie Microbienne, 1 Avenue Pierre Fabre, 66650, Banyuls sur Mer, France
| |
Collapse
|
5
|
Prevalence of Autotrophy in Non-humic African Lakes. Ecosystems 2022. [DOI: 10.1007/s10021-022-00783-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
6
|
Cabrerizo MJ, Medina-Sánchez JM, González-Olalla JM, Sánchez-Gómez D, Carrillo P. Microbial plankton responses to multiple environmental drivers in marine ecosystems with different phosphorus limitation degrees. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 816:151491. [PMID: 34752863 DOI: 10.1016/j.scitotenv.2021.151491] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/21/2021] [Accepted: 11/03/2021] [Indexed: 06/13/2023]
Abstract
Multiple drivers are threatening the functioning of the microbial food webs and trophic interactions. Our understanding about how temperature, CO2, nutrient inputs, and solar ultraviolet radiation (UVR) availability interact to alter ecosystem functioning is scarce because research has focused on single and double interactions. Moreover, the role that the degree of in situ nutrient limitation could play in the outcome of these interactions has been largely neglected, despite it is predominant in marine ecosystems. We address these uncertainties by combining remote-sensing analyses, and a collapsed experimental design with natural microbial communities from Mediterranean Sea and Atlantic Ocean exposed to temperature, nutrients, CO2, and UVR interactions. At the decade scale, we found that more intense and frequent (and longer lasting) Saharan dust inputs (and marine heatwaves) were only coupled with reduced phytoplankton biomass production. When microbial communities were concurrently exposed to future temperature, CO2, nutrient, and UVR conditions (i.e. the drivers studied over long-term scales), we found shifts from net autotrophy [primary production:respiration (PP:R) ratio > 1] towards a metabolic equilibrium (PP:R ratio ~ 1) or even a net heterotrophy (PP:R ratio < 1), as P-limitation degree was higher (i.e. Atlantic Ocean). These changes in the metabolic balance were coupled with a weakened phytoplankton-bacteria interaction (i.e. bacterial carbon demand exceeded phytoplankton carbon supply. Our work reveals that an accentuated in situ P limitation may promote reductions both in carbon uptake and fluxes between trophic levels in microbial plankton communities under global-change conditions. We show that considering long-term series can aid in identifying major local environmental drivers (i.e. temperature and nutrients in our case), easing the design of future global-change studies, but also that the abiotic environment to which microbial plankton communities are acclimated should be taken into account to avoid biased predictions concerning the effects of multiple interacting global-change drivers on marine ecosystems.
Collapse
Affiliation(s)
- Marco J Cabrerizo
- Departamento de Ecología y Biología Animal, Facultad de Ciencias del Mar, Universidad de Vigo, Campus Lagoas Marcosende s/n, 36310 Vigo, Spain; Centro de Investigación Mariña, Universidad de Vigo (CIM-UVigo), Illa de Toralla s/n, 36331 Vigo, Spain; Departamento de Ecología, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| | - Juan Manuel Medina-Sánchez
- Departamento de Ecología, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain; Instituto Universitario de Investigación del Agua, C/Ramón y Cajal, n 4, 18071 Granada, Spain
| | | | - Daniel Sánchez-Gómez
- Instituto Universitario de Investigación del Agua, C/Ramón y Cajal, n 4, 18071 Granada, Spain
| | - Presentación Carrillo
- Instituto Universitario de Investigación del Agua, C/Ramón y Cajal, n 4, 18071 Granada, Spain
| |
Collapse
|
7
|
Eigemann F, Rahav E, Grossart HP, Aharonovich D, Sher D, Vogts A, Voss M. Phytoplankton exudates provide full nutrition to a subset of accompanying heterotrophic bacteria via carbon, nitrogen and phosphorus allocation. Environ Microbiol 2022; 24:2467-2483. [PMID: 35146867 DOI: 10.1111/1462-2920.15933] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 02/03/2022] [Indexed: 11/28/2022]
Abstract
Marine bacteria rely on phytoplankton exudates as carbon sources (DOCp). Yet, it is unclear to what extent phytoplankton exudates also provide nutrients such as phytoplankton-derived N and P (DONp, DOPp). We address these questions by mesocosm exudate addition experiments with spent media from the ubiquitous pico-cyanobacterium Prochlorococcus to bacterial communities in contrasting ecosystems in the Eastern Mediterranean - a coastal and an open-ocean, oligotrophic station with and without on-top additions of inorganic nutrients. Inorganic nutrient addition did not lower the incorporation of exudate DONp, nor did it reduce alkaline phosphatase activity, suggesting that bacterial communities are able to exclusively cover their nitrogen and phosphorus demands with organic forms provided by phytoplankton exudates. Approximately half of the cells in each ecosystem took up detectable amounts of Prochlorococcus-derived C and N, yet based on 16S rRNA sequencing different bacterial genera were responsible for the observed exudate utilization patterns. In the coastal community, several phylotypes of Aureimarina, Psychrosphaera and Glaciecola responded positively to the addition of phytoplankton exudates, whereas phylotypes of Pseudoalteromonas increased and dominated the open-ocean communities. Together, our results strongly indicate that phytoplankton exudates provide coastal and open-ocean bacterial communities with organic carbon, nitrogen and phosphorus, and that phytoplankton exudate serve a full-fledged meal for the accompanying bacterial community in the nutrient-poor eastern Mediterranean. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Falk Eigemann
- Leibniz-Institute for Baltic Sea Research Warnemünde.,Water quality engineering, Technical University of Berlin
| | - Eyal Rahav
- Israel Oceanographic and Limnological Research, Haifa
| | | | | | - Daniel Sher
- Leon H. Charney School of Marine Sciences, University Haifa
| | - Angela Vogts
- Leibniz-Institute for Baltic Sea Research Warnemünde
| | - Maren Voss
- Leibniz-Institute for Baltic Sea Research Warnemünde
| |
Collapse
|
8
|
Cordone A, D’Errico G, Magliulo M, Bolinesi F, Selci M, Basili M, de Marco R, Saggiomo M, Rivaro P, Giovannelli D, Mangoni O. Bacterioplankton Diversity and Distribution in Relation to Phytoplankton Community Structure in the Ross Sea Surface Waters. Front Microbiol 2022; 13:722900. [PMID: 35154048 PMCID: PMC8828583 DOI: 10.3389/fmicb.2022.722900] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 01/05/2022] [Indexed: 01/04/2023] Open
Abstract
Primary productivity in the Ross Sea region is characterized by intense phytoplankton blooms whose temporal and spatial distribution are driven by changes in environmental conditions as well as interactions with the bacterioplankton community. However, the number of studies reporting the simultaneous diversity of the phytoplankton and bacterioplankton in Antarctic waters are limited. Here, we report data on the bacterial diversity in relation to phytoplankton community structure in the surface waters of the Ross Sea during the Austral summer 2017. Our results show partially overlapping bacterioplankton communities between the stations located in the Terra Nova Bay (TNB) coastal waters and the Ross Sea Open Waters (RSOWs), with a dominance of members belonging to the bacterial phyla Bacteroidetes and Proteobacteria. In the TNB coastal area, microbial communities were characterized by a higher abundance of sequences related to heterotrophic bacterial genera such as Polaribacter spp., together with higher phytoplankton biomass and higher relative abundance of diatoms. On the contrary, the phytoplankton biomass in the RSOW were lower, with relatively higher contribution of haptophytes and a higher abundance of sequences related to oligotrophic and mixothrophic bacterial groups like the Oligotrophic Marine Gammaproteobacteria (OMG) group and SAR11. We show that the rate of diversity change between the two locations is influenced by both abiotic (salinity and the nitrogen to phosphorus ratio) and biotic (phytoplankton community structure) factors. Our data provide new insight into the coexistence of the bacterioplankton and phytoplankton in Antarctic waters, suggesting that specific rather than random interaction contribute to the organic matter cycling in the Southern Ocean.
Collapse
Affiliation(s)
- Angelina Cordone
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Giuseppe D’Errico
- Department of Life Sciences, DISVA, Polytechnic University of Marche, Ancona, Italy
| | - Maria Magliulo
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Francesco Bolinesi
- Department of Biology, University of Naples Federico II, Naples, Italy
- *Correspondence: Francesco Bolinesi,
| | - Matteo Selci
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Marco Basili
- National Research Council, Institute of Marine Biological Resources and Biotechnologies CNR-IRBIM, Ancona, Italy
| | - Rocco de Marco
- National Research Council, Institute of Marine Biological Resources and Biotechnologies CNR-IRBIM, Ancona, Italy
| | | | - Paola Rivaro
- Department of Chemistry and Industrial Chemistry, University of Genoa, Genoa, Italy
| | - Donato Giovannelli
- Department of Biology, University of Naples Federico II, Naples, Italy
- Department of Life Sciences, DISVA, Polytechnic University of Marche, Ancona, Italy
- National Research Council, Institute of Marine Biological Resources and Biotechnologies CNR-IRBIM, Ancona, Italy
- Department of Marine and Coastal Science, Rutgers University, New Brunswick, NJ, United States
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Donato Giovannelli,
| | - Olga Mangoni
- Department of Biology, University of Naples Federico II, Naples, Italy
- Consorzio Nazionale Interuniversitario delle Scienze del Mare (CoNISMa), Rome, Italy
| |
Collapse
|
9
|
Morán XAG, García FC, Røstad A, Silva L, Al-Otaibi N, Irigoien X, Calleja ML. Diel dynamics of dissolved organic matter and heterotrophic prokaryotes reveal enhanced growth at the ocean's mesopelagic fish layer during daytime. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 804:150098. [PMID: 34508930 DOI: 10.1016/j.scitotenv.2021.150098] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 08/12/2021] [Accepted: 08/30/2021] [Indexed: 06/13/2023]
Abstract
Contrary to epipelagic waters, where biogeochemical processes closely follow the light and dark periods, little is known about diel cycles in the ocean's mesopelagic realm. Here, we monitored the dynamics of dissolved organic matter (DOM) and planktonic heterotrophic prokaryotes every 2 h for one day at 0 and 550 m (a depth occupied by vertically migrating fishes during light hours) in oligotrophic waters of the central Red Sea. We additionally performed predator-free seawater incubations of samples collected from the same site both at midnight and at noon. Comparable in situ variability in microbial biomass and dissolved organic carbon concentration suggests a diel supply of fresh DOM in both layers. The presence of fishes in the mesopelagic zone during daytime likely promoted a sustained, longer growth of larger prokaryotic cells. The specific growth rates were consistently higher in the noon experiments from both depths (surface: 0.34 vs. 0.18 d-1, mesopelagic: 0.16 vs. 0.09 d-1). Heterotrophic prokaryotes in the mesopelagic layer were also more efficient at converting extant DOM into new biomass. These results suggest that the ocean's twilight zone receives a consistent diurnal supply of labile DOM from the diel vertical migration of fishes, enabling an unexpectedly active community of heterotrophic prokaryotes.
Collapse
Affiliation(s)
- Xosé Anxelu G Morán
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Science & Engineering Division, 23955-6900 Thuwal, Saudi Arabia.
| | - Francisca C García
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Science & Engineering Division, 23955-6900 Thuwal, Saudi Arabia; Environment and Sustainability Institute, University of Exeter, TR10 9FE Penryn, United Kingdom
| | - Anders Røstad
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Science & Engineering Division, 23955-6900 Thuwal, Saudi Arabia
| | - Luis Silva
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Science & Engineering Division, 23955-6900 Thuwal, Saudi Arabia
| | - Najwa Al-Otaibi
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Science & Engineering Division, 23955-6900 Thuwal, Saudi Arabia; Department of Biology, College of Science, Taif University, Al-Hawiya 888, Saudi Arabia
| | | | - Maria Ll Calleja
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Science & Engineering Division, 23955-6900 Thuwal, Saudi Arabia; Max Planck Institute for Chemistry, 55128 Mainz, Germany
| |
Collapse
|
10
|
Pringault O, Bouvy M, Carre C, Mejri K, Bancon-Montigny C, Gonzalez C, Leboulanger C, Hlaili AS, Goni-Urriza M. Chemical contamination alters the interactions between bacteria and phytoplankton. CHEMOSPHERE 2021; 278:130457. [PMID: 34126687 DOI: 10.1016/j.chemosphere.2021.130457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 03/24/2021] [Accepted: 03/28/2021] [Indexed: 06/12/2023]
Abstract
Bacteria and phytoplankton are key players in aquatic ecosystem functioning. Their interactions mediate carbon transfer through the trophic web. Chemical contamination can alter the function and diversity of phytoplankton and bacterioplankton, with important consequences for ecosystem functioning. The aim of the present study was to assess the impact of chemical contamination on the interactions between both biological compartments. Two contrasting marine coastal ecosystems, offshore waters and lagoon waters, were exposed to chemical contamination (artificial or produced from resuspension of contaminated sediment) in microcosms in four seasons characterized by distinct phytoplankton communities. Offshore waters were characterized by a complex phytoplankton-bacterioplankton network with a predominance of positive interactions between both compartments, especially with Haptophyta, Cryptophyta, and dinoflagellates. In contrast, for lagoon waters, the phytoplankton-bacterioplankton network was simpler with a prevalence of negative interactions with Ochrophyta, Cryptophyta, and flagellates. Contamination with an artificial mix of pesticides and trace metal elements resulted in a decrease in the number of interactions between phytoplankton and bacterioplankton, especially for offshore waters. Resuspension of contaminated sediment also altered the interactions between both compartments. The release of nutrients stored in the sediment allowed the growth of nutrient limited phytoplankton species with marked consequences for the interactions with bacterioplankton, with a predominance of positive interactions, whereas in lagoon waters, negative interactions were mostly observed. Overall, this study showed that chemical contamination and sediment resuspension resulted in significant effects on phytoplankton-bacterioplankton interactions that can alter the functioning of anthropogenic coastal ecosystems.
Collapse
Affiliation(s)
- Olivier Pringault
- Aix Marseille Université, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France; MARBEC Univ Montpellier, IRD, Ifremer, Montpellier, France; Faculté des Sciences de Bizerte, Université de Carthage, 7021, Zarzouna, Bizerte, France.
| | - Marc Bouvy
- MARBEC Univ Montpellier, IRD, Ifremer, Montpellier, France
| | - Claire Carre
- MARBEC Univ Montpellier, IRD, Ifremer, Montpellier, France
| | - Kaouther Mejri
- Faculté des Sciences de Bizerte, Université de Carthage, 7021, Zarzouna, Bizerte, France
| | | | | | | | - Asma Sakka Hlaili
- Faculté des Sciences de Bizerte, Université de Carthage, 7021, Zarzouna, Bizerte, France; Laboratoire d'Ecologie, de Biologie et de Physiologie des Organismes Aquatiques, LR18ES41, Université de Tunis El Manar, Tunis, France
| | - Marisol Goni-Urriza
- Universite de Pau et des Pays de L'Adour, E2S UPPA, CNRS, IPREM, 64000, Pau, France
| |
Collapse
|
11
|
Silva L, Calleja ML, Ivetic S, Huete-Stauffer T, Roth F, Carvalho S, Morán XAG. Heterotrophic bacterioplankton responses in coral- and algae-dominated Red Sea reefs show they might benefit from future regime shift. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141628. [PMID: 32896805 DOI: 10.1016/j.scitotenv.2020.141628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/06/2020] [Accepted: 08/09/2020] [Indexed: 06/11/2023]
Abstract
In coral reefs, dissolved organic matter (DOM) cycling is a critical process for sustaining ecosystem functioning. However, global and local stressors have caused persistent shifts from coral- to algae-dominated benthic communities. The influence of such phase shifts on DOM nature and its utilization by heterotrophic bacterioplankton remains poorly studied. Every second month for one year, we retrieved seawater samples enriched in DOM produced by coral- and algae-dominated benthic communities in a central Red Sea reef during a full annual cycle. Seawater incubations were conducted in the laboratory under in situ temperature and light conditions by inoculating enriched DOM samples with bacterial assemblages collected in the surrounding waters. Dissolved organic carbon (DOC) concentrations were higher in the warmer months (May-September) in both communities, resulting in higher specific growth rates and bacterial growth efficiencies (BGE). However, these high summer values were significantly enhanced in algal-DOM relative to coral-DOM, suggesting the potential for bacterioplankton biomass increase in reefs with algae replacing healthy coral cover under warmer conditions. The potential exacerbation of heterotrophic bacterial activity in the ongoing widespread regime shift from coral- to algae-dominated communities may have detrimental consequences for the overall health of tropical coral reefs.
Collapse
Affiliation(s)
- Luis Silva
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia.
| | - Maria Ll Calleja
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia; Department of Climate Geochemistry, Max Planck Institute for Chemistry (MPIC), Hahn-Meitner-Weg 1, 55128 Mainz, Germany
| | | | - Tamara Huete-Stauffer
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
| | - Florian Roth
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia; Baltic Sea Centre, Stockholm University, 11418 Stockholm, Sweden; Tvärminne Zoological Station, University of Helsinki, 00100 Helsinki, Finland
| | - Susana Carvalho
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
| | - Xosé Anxelu G Morán
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
| |
Collapse
|
12
|
Pringault O, Bouvy M, Carre C, Fouilland E, Meddeb M, Mejri K, Leboulanger C, Sakka Hlaili A. Impacts of chemical contamination on bacterio-phytoplankton coupling. CHEMOSPHERE 2020; 257:127165. [PMID: 32480088 DOI: 10.1016/j.chemosphere.2020.127165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
Phytoplankton and bacterioplankton are the key components of the organic matter cycle in aquatic ecosystems, and their interactions can impact the transfer of carbon and ecosystem functioning. The aim of this work was to assess the consequences of chemical contamination on the coupling between phytoplankton and bacterioplankton in two contrasting marine coastal ecosystems: lagoon waters and offshore waters. Bacterial carbon demand was sustained by primary carbon production in the offshore situation, suggesting a tight coupling between both compartments. In contrast, in lagoon waters, due to a higher nutrient and organic matter availability, bacteria could rely on allochthonous carbon sources to sustain their carbon requirements, decreasing so the coupling between both compartments. Exposure to chemical contaminants, pesticides and metal trace elements, resulted in a significant inhibition of the metabolic activities (primary production and bacterial carbon demand) involved in the carbon cycle, especially in offshore waters during spring and fall, inducing a significant decrease of the coupling between primary producers and heterotrophs. This coupling loss was even more evident upon sediment resuspension for both ecosystems due to the important release of nutrients and organic matter. Resulting enrichment alleviated the toxic effects of contaminants as indicated by the stimulation of phytoplankton biomass and carbon production, and modified the composition of the phytoplankton community, impacting so the interactions between phytoplankton and bacterioplankton.
Collapse
Affiliation(s)
- Olivier Pringault
- Aix Marseille Univ, Universite de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France; MARBEC Univ Montpellier, IRD, Ifremer, Montpellier, France; Faculté des Sciences de Bizerte, Université de Carthage, 7021, Zarzouna, Tunisia.
| | - Marc Bouvy
- MARBEC Univ Montpellier, IRD, Ifremer, Montpellier, France
| | - Claire Carre
- MARBEC Univ Montpellier, IRD, Ifremer, Montpellier, France
| | - Eric Fouilland
- MARBEC Univ Montpellier, IRD, Ifremer, Montpellier, France
| | - Marouan Meddeb
- Faculté des Sciences de Bizerte, Université de Carthage, 7021, Zarzouna, Tunisia
| | - Kaouther Mejri
- Faculté des Sciences de Bizerte, Université de Carthage, 7021, Zarzouna, Tunisia
| | | | - Asma Sakka Hlaili
- Faculté des Sciences de Bizerte, Université de Carthage, 7021, Zarzouna, Tunisia; Laboratory of Environmental Sciences, Biology and Physiology of Aquatic Organisms LR18ES41, University El Manar of Tunis, Faculty of Sciences of Tunis, Tunis, Tunisia
| |
Collapse
|
13
|
González-Benítez N, García-Corral LS, Morán XAG, Middelburg JJ, Pizay MD, Gattuso JP. Drivers of Microbial Carbon Fluxes Variability in Two Oligotrophic Mediterranean Coastal Systems. Sci Rep 2019; 9:17669. [PMID: 31776462 PMCID: PMC6881365 DOI: 10.1038/s41598-019-53650-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 10/28/2019] [Indexed: 11/09/2022] Open
Abstract
The carbon fluxes between phytoplankton and heterotrophic bacterioplankton were studied in two coastal oligotrophic sites in the NW Mediterranean. Phytoplankton and bacterial production rates were measured under natural conditions using different methods. In the Bay of Villefranche, the temporal variability revealed net heterotrophy in July-October and net autotrophy in December-March. The spatial variability was studied in the Bay of Palma, showing net autotrophic areas in the west and heterotrophic areas in the east. On average bacterial respiration, represented 62% of the total community respiration. Bacterial growth efficiency (BGE) values were significantly higher in autotrophic conditions than in heterotrophic ones. During autotrophic periods, dissolved primary production (DPP) was enough to sustained bacterial metabolism, although it showed a positive correlation with organic carbon stock (DOC). Under heterotrophic conditions, DPP did not sustain bacterial metabolism but bacterial respiration correlated with DPP and bacterial production with DOC. Temperature affected positively, DOC, BGE, bacterial respiration and production when the trophic status was autotrophic. To summarize, the response of bacterial metabolism to temperature and carbon sources depends on the trophic status within these oligotrophic coastal systems.
Collapse
Affiliation(s)
- Natalia González-Benítez
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230, Villefranche-sur-mer, France. .,Institute for Sustainable Development and International Relations, Sciences Po, 27 rue Saint Guillaume, F-75007, Paris, France. .,Department of Biology, Geology, Physics and Inorganic Chemistry, King Juan Carlos University, C/Tulipán s/n, 28933, Móstoles, Madrid, Spain.
| | - Lara S García-Corral
- Department of Biology, Geology, Physics and Inorganic Chemistry, King Juan Carlos University, C/Tulipán s/n, 28933, Móstoles, Madrid, Spain
| | - Xosé Anxelu G Morán
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, 23955-6900, Thuwal, Saudi Arabia
| | - Jack J Middelburg
- Department of Estuarine and Delta Systems, NIOZ Royal Netherlands Institute for Sea Research and Utrecht University, Yerseke, The Netherlands.,Department of Earth Sciences, Utrecht University, Princetonlaan 8A, 3584 CB, Utrecht, The Netherlands
| | - Marie Dominique Pizay
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230, Villefranche-sur-mer, France.,Institute for Sustainable Development and International Relations, Sciences Po, 27 rue Saint Guillaume, F-75007, Paris, France
| | - Jean-Pierre Gattuso
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230, Villefranche-sur-mer, France.,Institute for Sustainable Development and International Relations, Sciences Po, 27 rue Saint Guillaume, F-75007, Paris, France
| |
Collapse
|
14
|
Cabrerizo MJ, Medina-Sánchez JM, Villar-Argaiz M, Carrillo P. Interplay between resistance and resilience governs the stability of a freshwater microbial food web under multiple stressors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 691:908-918. [PMID: 31326814 DOI: 10.1016/j.scitotenv.2019.07.173] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/09/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
Energy (photosynthetically active [PAR] and ultraviolet [UVR] radiation) and matter (organic and inorganic nutrients) fluxes regulate the ecosystem's stability. However, the mechanisms underpinning the potential interplay between resistance and resilience to shifts in nutrient inputs and UVR are poorly understood. To assess how the UVR × nutrients interaction alters ecosystem stability, we exposed in situ a microbial food web from an oligotrophic ecosystem to: (1) two light (UVR + PAR and PAR), and (2) four nutrient (ambient concentrations, phosphorus [P], carbon [C] and C × P addition) treatments for three weeks. During this period, we quantified the community composition and biomass, sestonic P and C:P ratio, primary [PP] and bacterial [BP] production, community [CR] and bacterial [BR] respiration, excreted organic carbon [EOC], as well as the commensalistic phytoplankton-bacteria interaction (i.e. bacterial carbon demand [BCD]:EOC ratio) and the metabolic balance of the ecosystem (i.e. [PP:R] ratio). The stability of all response variables under the four environmental scenarios tested (i.e. UVR, UVR × C, UVR × P, and UVR × C × P) was quantified by means of the resistance and resilience indexes. The microbial community was dominated by phototrophs during the experimental period regardless of the treatment considered. The most complex scenario, i.e. UVR × C × P, decreased the resistance for all variables, except for BR and the PP:R ratio. Despite that PP:R ratio showed the highest resistance under such scenario, it was >1 in all environmental scenarios (i.e. net autotrophic), except under the UVR × C interaction, where, concomitant with increased resilience, the balance shifted towards net heterotrophy (PP:R < 1). Under the UVR × C × P scenario, the metabolic balance of the ecosystem proved strongly resistant due mainly to high resistance of bacterial respiration and a firm stability of the commensalistic interaction. Our results evidence that the high resilience of phototrophs (favoring their predominance over mixo- and heterotrophs) may lead to the maintenance of the autotrophic nature and carbon (C) sink capacity of the ecosystem.
Collapse
Affiliation(s)
- Marco J Cabrerizo
- Departamento de Ecología y Biología Animal, Facultad de Ciencias del Mar, Campus Lagoas Marcosende s/n, 36310 Vigo, Spain; Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, 4, 18071 Granada, Spain.
| | - Juan Manuel Medina-Sánchez
- Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, 4, 18071 Granada, Spain.
| | - Manuel Villar-Argaiz
- Departamento de Ecología, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| | - Presentación Carrillo
- Instituto Universitario de Investigación del Agua, Universidad de Granada, C/ Ramón y Cajal, 4, 18071 Granada, Spain.
| |
Collapse
|
15
|
Silva L, Calleja ML, Huete-Stauffer TM, Ivetic S, Ansari MI, Viegas M, Morán XAG. Low Abundances but High Growth Rates of Coastal Heterotrophic Bacteria in the Red Sea. Front Microbiol 2019; 9:3244. [PMID: 30666244 PMCID: PMC6330340 DOI: 10.3389/fmicb.2018.03244] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 12/13/2018] [Indexed: 11/29/2022] Open
Abstract
Characterized by some of the highest naturally occurring sea surface temperatures, the Red Sea remains unexplored regarding the dynamics of heterotrophic prokaryotes. Over 16 months, we used flow cytometry to characterize the abundance and growth of four physiological groups of heterotrophic bacteria: membrane-intact (Live), high and low nucleic acid content (HNA and LNA) and actively respiring (CTC+) cells in shallow coastal waters. Chlorophyll a, dissolved organic matter (DOC and DON) concentrations, and their fluorescent properties were also measured as proxies of bottom-up control. We performed short-term incubations (6 days) with the whole microbial community (Community treatment), and with the bacterial community only after removing predators by filtration (Filtered treatment). Initial bacterial abundances ranged from 1.46 to 4.80 × 105 cells mL-1. Total specific growth rates in the Filtered treatment ranged from 0.76 to 2.02 d-1. Live and HNA cells displayed similar seasonal patterns, with higher values during late summer and fall (2.13 and 2.33 d-1, respectively) and lower in late spring (1.02 and 1.01 d-1, respectively). LNA cells were outgrown by the other physiological groups (0.33-1.08 d-1) while CTC+ cells (0.28-1.85 d-1) showed weaker seasonality. The Filtered treatment yielded higher bacterial abundances than the Community treatment in all but 2 of the incubations, and carrying capacities peaked in November 2016 (1.04 × 106 cells mL-1), with minimum values (3.61 × 105 cells mL-1) observed in May 2017. The high temperatures experienced from May through October 2016 (33.4 ± 0.4°C) did not constrain the growth of heterotrophic bacteria. Indeed, bacterial growth efficiencies were positively correlated with environmental temperature, reflecting the presence of more labile compounds (high DON concentrations resulting in lower C:N ratios) in summer. The overall high specific growth rates and the consistently higher carrying capacities in the Filtered treatment suggest that strong top-down control by protistan grazers was the likely cause for the low heterotrophic bacteria abundances.
Collapse
Affiliation(s)
- Luis Silva
- Division of Biological and Environmental Sciences and Engineering, Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | | | | | | | | | | | - Xosé Anxelu G. Morán
- Division of Biological and Environmental Sciences and Engineering, Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| |
Collapse
|
16
|
Hernando-Morales V, Varela MM, Needham DM, Cram J, Fuhrman JA, Teira E. Vertical and Seasonal Patterns Control Bacterioplankton Communities at Two Horizontally Coherent Coastal Upwelling Sites off Galicia (NW Spain). MICROBIAL ECOLOGY 2018; 76:866-884. [PMID: 29675703 DOI: 10.1007/s00248-018-1179-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 03/14/2018] [Indexed: 06/08/2023]
Abstract
Analysis of seasonal patterns of marine bacterial community structure along horizontal and vertical spatial scales can help to predict long-term responses to climate change. Several recent studies have shown predictable seasonal reoccurrence of bacterial assemblages. However, only a few have assessed temporal variability over both horizontal and vertical spatial scales. Here, we simultaneously studied the bacterial community structure at two different locations and depths in shelf waters of a coastal upwelling system during an annual cycle. The most noticeable biogeographic patterns observed were seasonality, horizontal homogeneity, and spatial synchrony in bacterial diversity and community structure related with regional upwelling-downwelling dynamics. Water column mixing eventually disrupted bacterial community structure vertical heterogeneity. Our results are consistent with previous temporal studies of marine bacterioplankton in other temperate regions and also suggest a marked influence of regional factors on the bacterial communities inhabiting this coastal upwelling system. Bacterial-mediated carbon fluxes in this productive region appear to be mainly controlled by community structure dynamics in surface waters, and local environmental factors at the base of the euphotic zone.
Collapse
Affiliation(s)
- Víctor Hernando-Morales
- Grupo de Oceanografía Biolóxica, Departamento de Ecoloxía e Bioloxía Animal, Universidade de Vigo, 36310, Vigo, Spain.
- Estación de Ciencias Mariñas de Toralla (ECIMAT), Universidade de Vigo, Illa de Toralla, 36331, Vigo, Spain.
| | - Marta M Varela
- IEO, Instituto Español de Oceanografía, Centro Oceanográfico de A Coruña, Apdo 130, 15080, A Coruña, Spain
| | - David M Needham
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, 90089-0371, USA
| | - Jacob Cram
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, 90089-0371, USA
- School of Oceanography, University of Washington, Seattle, WA, 98195, USA
| | - Jed A Fuhrman
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, 90089-0371, USA
| | - Eva Teira
- Grupo de Oceanografía Biolóxica, Departamento de Ecoloxía e Bioloxía Animal, Universidade de Vigo, 36310, Vigo, Spain
- Estación de Ciencias Mariñas de Toralla (ECIMAT), Universidade de Vigo, Illa de Toralla, 36331, Vigo, Spain
| |
Collapse
|
17
|
Marisol GU, Hélène M, Céline L, Claire C, Marc B, Asma SH, Olivier P. Consequences of contamination on the interactions between phytoplankton and bacterioplankton. CHEMOSPHERE 2018; 195:212-222. [PMID: 29268179 DOI: 10.1016/j.chemosphere.2017.12.053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 11/14/2017] [Accepted: 12/08/2017] [Indexed: 06/07/2023]
Abstract
Sediment resuspension can provoke strong water enrichment in nutrients, contaminants, and microorganisms. Microcosm incubations were performed in triplicate for 96 h, with lagoon and offshore waters incubated either with sediment elutriate or with an artificial mixture of contaminants issued from sediment resuspension. Sediment elutriate provoked a strong increase in microbial biomass, with little effects on the phytoplankton and bacterioplankton community structures. Among the pool of contaminants released, few were clearly identified as structuring factors of phytoplankton and bacterioplankton communities, namely simazine, Cu, Sn, Ni, and Cr. Effects were more pronounced in the offshore waters, suggesting a relative tolerance of the lagoon microbial communities to contamination. The impacts of contamination on the microbial community structure were direct or indirect, depending on the nature and the strength of the interactions between phytoplankton and bacterioplankton.
Collapse
Affiliation(s)
- Goni-Urriza Marisol
- CNRS/ Univ Pau & Pays Adour, Institut des Sciences Analytiques et de Physico-Chimie Pour L'Environnement et les Materiaux, UMR5254, 64000, Pau, France
| | - Moussard Hélène
- CNRS/ Univ Pau & Pays Adour, Institut des Sciences Analytiques et de Physico-Chimie Pour L'Environnement et les Materiaux, UMR5254, 64000, Pau, France; UMR 9190 Marbec IRD-Ifremer-CNRS-Universite de Montpellier, Place Eugene Bataillon, Case 093, 34095, Montpellier Cedex 5, France
| | - Lafabrie Céline
- UMR 9190 Marbec IRD-Ifremer-CNRS-Universite de Montpellier, Place Eugene Bataillon, Case 093, 34095, Montpellier Cedex 5, France
| | - Carre Claire
- UMR 9190 Marbec IRD-Ifremer-CNRS-Universite de Montpellier, Place Eugene Bataillon, Case 093, 34095, Montpellier Cedex 5, France
| | - Bouvy Marc
- UMR 9190 Marbec IRD-Ifremer-CNRS-Universite de Montpellier, Place Eugene Bataillon, Case 093, 34095, Montpellier Cedex 5, France
| | - Sakka Hlaili Asma
- Faculte des Sciences de Bizerte, Universite de Carthage, 7021, Zarzouna, Tunisie
| | - Pringault Olivier
- UMR 9190 Marbec IRD-Ifremer-CNRS-Universite de Montpellier, Place Eugene Bataillon, Case 093, 34095, Montpellier Cedex 5, France; Faculte des Sciences de Bizerte, Universite de Carthage, 7021, Zarzouna, Tunisie.
| |
Collapse
|
18
|
Large Plankton Enhance Heterotrophy Under Experimental Warming in a Temperate Coastal Ecosystem. Ecosystems 2017. [DOI: 10.1007/s10021-017-0208-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
19
|
Silveira CB, Cavalcanti GS, Walter JM, Silva-Lima AW, Dinsdale EA, Bourne DG, Thompson CC, Thompson FL. Microbial processes driving coral reef organic carbon flow. FEMS Microbiol Rev 2017; 41:575-595. [PMID: 28486655 DOI: 10.1093/femsre/fux018] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 04/10/2017] [Indexed: 01/13/2023] Open
Abstract
Coral reefs are one of the most productive ecosystems on the planet, with primary production rates compared to that of rain forests. Benthic organisms release 10-50% of their gross organic production as mucus that stimulates heterotrophic microbial metabolism in the water column. As a result, coral reef microbes grow up to 50 times faster than open ocean communities. Anthropogenic disturbances cause once coral-dominated reefs to become dominated by fleshy organisms, with several outcomes for trophic relationships. Here we review microbial processes implicated in organic carbon flux in coral reefs displaying species phase shifts. The first section presents microbial players and interactions within the coral holobiont that contribute to reef carbon flow. In the second section, we identify four ecosystem-level microbial features that directly respond to benthic species phase shifts: community composition, biomass, metabolism and viral predation. The third section discusses the significance of microbial consumption of benthic organic matter to reef trophic relationships. In the fourth section, we propose that the 'microbial phase shifts' discussed here are conducive to lower resilience, facilitating the transition to new degradation states in coral reefs.
Collapse
Affiliation(s)
- Cynthia B Silveira
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil.,Biology Department, San Diego State University, 5500 Campanille Dr, San Diego, CA 92182, USA
| | - Giselle S Cavalcanti
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil.,Biology Department, San Diego State University, 5500 Campanille Dr, San Diego, CA 92182, USA
| | - Juline M Walter
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
| | - Arthur W Silva-Lima
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
| | - Elizabeth A Dinsdale
- Biology Department, San Diego State University, 5500 Campanille Dr, San Diego, CA 92182, USA
| | - David G Bourne
- College of Science and Engineering, James Cook University and Australian Institute of Marine Science, Townsville, Queensland 4810, Australia
| | - Cristiane C Thompson
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
| | - Fabiano L Thompson
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
| |
Collapse
|
20
|
Evans C, Brandsma J, Pond DW, Venables HJ, Meredith MP, Witte HJ, Stammerjohn S, Wilson WH, Clarke A, Brussaard CPD. Drivers of interannual variability in virioplankton abundance at the coastal western Antarctic peninsula and the potential effects of climate change. Environ Microbiol 2017; 19:740-755. [PMID: 27902869 DOI: 10.1111/1462-2920.13627] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An 8-year time-series in the Western Antarctic Peninsula (WAP) with an approximately weekly sampling frequency was used to elucidate changes in virioplankton abundance and their drivers in this climatically sensitive region. Virioplankton abundances at the coastal WAP show a pronounced seasonal cycle with interannual variability in the timing and magnitude of the summer maxima. Bacterioplankton abundance is the most influential driving factor of the virioplankton, and exhibit closely coupled dynamics. Sea ice cover and duration predetermine levels of phytoplankton stock and thus, influence virioplankton by dictating the substrates available to the bacterioplankton. However, variations in the composition of the phytoplankton community and particularly the prominence of Diatoms inferred from silicate drawdown, drive interannual differences in the magnitude of the virioplankton bloom; likely again mediated through changes in the bacterioplankton. Their findings suggest that future warming within the WAP will cause changes in sea ice that will influence viruses and their microbial hosts through changes in the timing, magnitude and composition of the phytoplankton bloom. Thus, the flow of matter and energy through the viral shunt may be decreased with consequences for the Antarctic food web and element cycling.
Collapse
Affiliation(s)
- Claire Evans
- Department of Biological Oceanography, Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Joost Brandsma
- Department of Biological Oceanography, Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - David W Pond
- British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Hugh J Venables
- British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Michael P Meredith
- British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Harry J Witte
- Department of Biological Oceanography, Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Sharon Stammerjohn
- Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA
| | - William H Wilson
- The Laboratory, Sir Alister Hardy Foundation for Ocean Science, Citadel Hill, Plymouth, PL1 2PB, UK
| | - Andrew Clarke
- British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Corina P D Brussaard
- Department of Biological Oceanography, Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands.,Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94248, Amsterdam, 1090 GE, The Netherlands
| |
Collapse
|
21
|
Rising nutrient-pulse frequency and high UVR strengthen microbial interactions. Sci Rep 2017; 7:43615. [PMID: 28252666 PMCID: PMC5333626 DOI: 10.1038/srep43615] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 01/26/2017] [Indexed: 01/13/2023] Open
Abstract
Solar radiation and nutrient pulses regulate the ecosystem’s functioning. However, little is known about how a greater frequency of pulsed nutrients under high ultraviolet radiation (UVR) levels, as expected in the near future, could alter the responses and interaction between primary producers and decomposers. In this report, we demonstrate through a mesocosm study in lake La Caldera (Spain) that a repeated (press) compared to a one-time (pulse) schedule under UVR prompted higher increases in primary (PP) than in bacterial production (BP) coupled with a replacement of photoautotrophs by mixotrophic nanoflagellates (MNFs). The mechanism underlying these amplified phytoplanktonic responses was a dual control by MNFs on bacteria through the excretion of organic carbon and an increased top-down control by bacterivory. We also show across a 6-year whole-lake study that the changes from photoautotrophs to MNFs were related mainly to the frequency of pulsed nutrients (e.g. desert dust inputs). Our results underscore how an improved understanding of the interaction between chronic and stochastic environmental factors is critical for predicting ongoing changes in ecosystem functioning and its responses to climatically driven changes.
Collapse
|
22
|
Luria CM, Amaral-Zettler LA, Ducklow HW, Rich JJ. Seasonal Succession of Free-Living Bacterial Communities in Coastal Waters of the Western Antarctic Peninsula. Front Microbiol 2016; 7:1731. [PMID: 27857708 PMCID: PMC5093341 DOI: 10.3389/fmicb.2016.01731] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 10/17/2016] [Indexed: 01/05/2023] Open
Abstract
The marine ecosystem along the Western Antarctic Peninsula undergoes a dramatic seasonal transition every spring, from almost total darkness to almost continuous sunlight, resulting in a cascade of environmental changes, including phytoplankton blooms that support a highly productive food web. Despite having important implications for the movement of energy and materials through this ecosystem, little is known about how these changes impact bacterial succession in this region. Using 16S rRNA gene amplicon sequencing, we measured changes in free-living bacterial community composition and richness during a 9-month period that spanned winter to the end of summer. Chlorophyll a concentrations were relatively low until summer when a major phytoplankton bloom occurred, followed 3 weeks later by a high peak in bacterial production. Richness in bacterial communities varied between ~1,200 and 1,800 observed operational taxonomic units (OTUs) before the major phytoplankton bloom (out of ~43,000 sequences per sample). During peak bacterial production, OTU richness decreased to ~700 OTUs. The significant decrease in OTU richness only lasted a few weeks, after which time OTU richness increased again as bacterial production declined toward pre-bloom levels. OTU richness was negatively correlated with bacterial production and chlorophyll a concentrations. Unlike the temporal pattern in OTU richness, community composition changed from winter to spring, prior to onset of the summer phytoplankton bloom. Community composition continued to change during the phytoplankton bloom, with increased relative abundance of several taxa associated with phytoplankton blooms, particularly Polaribacter. Bacterial community composition began to revert toward pre-bloom conditions as bacterial production declined. Overall, our findings clearly demonstrate the temporal relationship between phytoplankton blooms and seasonal succession in bacterial growth and community composition. Our study highlights the importance of high-resolution time series sampling, especially during the relatively under-sampled Antarctic winter and spring, which enabled us to discover seasonal changes in bacterial community composition that preceded the summertime phytoplankton bloom.
Collapse
Affiliation(s)
- Catherine M Luria
- Department of Ecology and Evolutionary Biology, Brown University, Providence RI, USA
| | - Linda A Amaral-Zettler
- The Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods HoleMA, USA; Department of Earth, Environmental and Planetary Sciences, Brown University, ProvidenceRI, USA
| | - Hugh W Ducklow
- Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory of Columbia University, Palisades NY, USA
| | - Jeremy J Rich
- School of Marine Sciences and Darling Marine Center, University of Maine, Walpole ME, USA
| |
Collapse
|
23
|
Trottet A, Leboulanger C, Vidussi F, Pete R, Bouvy M, Fouilland E. Heterotrophic Bacteria Show Weak Competition for Nitrogen in Mediterranean Coastal Waters (Thau Lagoon) in Autumn. MICROBIAL ECOLOGY 2016; 71:304-314. [PMID: 26358721 DOI: 10.1007/s00248-015-0658-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 08/03/2015] [Indexed: 06/05/2023]
Abstract
The importance of heterotrophic bacteria relative to phytoplankton in the uptake of ammonium and nitrate was studied in Mediterranean coastal waters (Thau Lagoon) during autumn, when the Mediterranean Sea received the greatest allochthonous nutrient loads. Specific inhibitors and size-fractionation methods were used in combination with isotopic (15)N tracers. NO3 (-) and NH4 (+) uptake was dominated by phytoplankton (60 % on average) during the study period, which included a flood event. Despite lower biomass specific NH4 (+) and NO3 uptake rates, free-living heterotrophic bacteria contributed significantly (>30 %) to total microbial NH4 (+) and NO3 (-) uptake rates in low chlorophyll waters. Under these conditions, heterotrophic bacteria may be responsible for more than 50 % of primary production, using very little freshly produced phytoplankton exudates. In low chlorophyll coastal waters as reported during the present 3-month study, the heterotrophic bacteria seemed to depend to a greater extent on allochthonous N and C substrates than on autochthonous substrates derived from phytoplankton.
Collapse
Affiliation(s)
- Aurore Trottet
- Laboratoire Ecologie des Systèmes Marins Côtiers, UMR 5119 ECOSYM (Université Montpellier 2-CNRS-IRD IFREMER, Université Montpellier 1), Montpellier, France
- Station Marine de l'Environnement Littoral, 2 rue des Chantiers, 34200, Sète, France
- DHI Water & Environment (S) Pte Ltd, 1 Cleantech Loop #03-05 CleanTech One, Singapore, 637141, Singapore
| | - Christophe Leboulanger
- Laboratoire Ecologie des Systèmes Marins Côtiers, UMR 5119 ECOSYM (Université Montpellier 2-CNRS-IRD IFREMER, Université Montpellier 1), Montpellier, France
- UMR 9190 MARBEC (CNRS-UM-IRD IFREMER), Montpellier, France
- Station Marine de l'Environnement Littoral, 2 rue des Chantiers, 34200, Sète, France
| | - Francesca Vidussi
- Laboratoire Ecologie des Systèmes Marins Côtiers, UMR 5119 ECOSYM (Université Montpellier 2-CNRS-IRD IFREMER, Université Montpellier 1), Montpellier, France
- UMR 9190 MARBEC (CNRS-UM-IRD IFREMER), Montpellier, France
- Université de Montpellier, Place E. Bataillon, CC 093, 34095, Montpellier, France
| | - Romain Pete
- Laboratoire Ecologie des Systèmes Marins Côtiers, UMR 5119 ECOSYM (Université Montpellier 2-CNRS-IRD IFREMER, Université Montpellier 1), Montpellier, France
- UMR 9190 MARBEC (CNRS-UM-IRD IFREMER), Montpellier, France
| | - Marc Bouvy
- Laboratoire Ecologie des Systèmes Marins Côtiers, UMR 5119 ECOSYM (Université Montpellier 2-CNRS-IRD IFREMER, Université Montpellier 1), Montpellier, France
- UMR 9190 MARBEC (CNRS-UM-IRD IFREMER), Montpellier, France
- Université de Montpellier, Place E. Bataillon, CC 093, 34095, Montpellier, France
| | - Eric Fouilland
- Laboratoire Ecologie des Systèmes Marins Côtiers, UMR 5119 ECOSYM (Université Montpellier 2-CNRS-IRD IFREMER, Université Montpellier 1), Montpellier, France.
- UMR 9190 MARBEC (CNRS-UM-IRD IFREMER), Montpellier, France.
- Station Marine de l'Environnement Littoral, 2 rue des Chantiers, 34200, Sète, France.
| |
Collapse
|
24
|
Pringault O, Lafabrie C, Avezac M, Bancon-Montigny C, Carre C, Chalghaf M, Delpoux S, Duvivier A, Elbaz-Poulichet F, Gonzalez C, Got P, Leboulanger C, Spinelli S, Hlaili AS, Bouvy M. Consequences of contaminant mixture on the dynamics and functional diversity of bacterioplankton in a southwestern Mediterranean coastal ecosystem. CHEMOSPHERE 2016; 144:1060-1073. [PMID: 26451655 DOI: 10.1016/j.chemosphere.2015.09.093] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 09/14/2015] [Accepted: 09/24/2015] [Indexed: 06/05/2023]
Abstract
Contamination of coastal environments is often due to a complex mixture of pollutants, sometimes in trace levels, that may have significant effects on diversity and function of organisms. The aim of this study was to evaluate the short-term dynamics of bacterioplankton exposed to natural and artificial mixtures of contaminants. Bacterial communities from a southwestern Mediterranean ecosystem, lagoon and the bay (offshore) of Bizerte were exposed to i) elutriate from resuspension of contaminated sediment, and ii) an artificial mixture of metals and herbicides mimicking the contamination observed during sediment resuspension. Elutriate incubation as well as artificial spiking induced strong enrichments in nutrients (up to 18 times), metals (up to six times) and herbicides (up to 20 times) relative to the in situ concentrations in the offshore station, whereas the increases in contaminants were less marked in the lagoon station. In the offshore waters, the artificial mixture of pollutants provoked a strong inhibition of bacterial abundance, production and respiration and significant modifications of the potential functional diversity of bacterioplankton with a strong decrease of the carbohydrate utilization. In contrast, incubation with elutriate resulted in a stimulation of bacterial activities and abundances, suggesting that the toxic effects of pollutants were modified by the increase in nutrient and DOM concentrations due to the sediment resuspension. The effects of elutriate and the artificial mixture of pollutants on bacterial dynamics and the functional diversity were less marked in the lagoon waters, than in offshore waters, suggesting a relative tolerance of lagoon bacteria against contaminants.
Collapse
Affiliation(s)
- Olivier Pringault
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France; Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Tunisia.
| | - Céline Lafabrie
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France; Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Tunisia
| | - Murielle Avezac
- Ecole des Mines d'Alès, LGEI, 6 Avenue de Clavières, 30319 Alès Cedex, France
| | - Chrystelle Bancon-Montigny
- UMR 5569 HYDROSCIENCES IRD-CNRS-Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
| | - Claire Carre
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France
| | - Mohamed Chalghaf
- Institut Supérieur de Pêche et d'Aquaculture de Bizerte, 7021 Zarzouna, Tunisia
| | - Sophie Delpoux
- UMR 5569 HYDROSCIENCES IRD-CNRS-Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
| | - Adrien Duvivier
- UMR 5569 HYDROSCIENCES IRD-CNRS-Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
| | - Françoise Elbaz-Poulichet
- UMR 5569 HYDROSCIENCES IRD-CNRS-Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
| | - Catherine Gonzalez
- Ecole des Mines d'Alès, LGEI, 6 Avenue de Clavières, 30319 Alès Cedex, France
| | - Patrice Got
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France
| | - Christophe Leboulanger
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France
| | - Sylvie Spinelli
- Ecole des Mines d'Alès, LGEI, 6 Avenue de Clavières, 30319 Alès Cedex, France
| | - Asma Sakka Hlaili
- Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Tunisia
| | - Marc Bouvy
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, Case 093, 34095 Montpellier Cedex 5, France
| |
Collapse
|
25
|
Pringault O, Aube J, Bouchez O, Klopp C, Mariette J, Escudie F, Senin P, Goni-Urriza M. Contrasted effects of natural complex mixtures of PAHs and metals on oxygen cycle in a microbial mat. CHEMOSPHERE 2015; 135:189-201. [PMID: 25957138 DOI: 10.1016/j.chemosphere.2015.04.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 03/18/2015] [Accepted: 04/14/2015] [Indexed: 06/04/2023]
Abstract
The contamination of polluted environments is often due to a complex mixture of pollutants sometimes at trace levels which nevertheless may have significant effects on the diversity and functioning of organisms. The aim of this study was to assess the functional responses of a microbial mat exposed to a natural complex mixture of PAHs and metals as a function of the maturation stage of the biofilm. Microbial mats sampled in a slightly polluted environment were exposed to contaminated water of a retention basin of an oil refinery. The responses of the microbial mats differed according to season. In spring 2012, strong inhibition of both oxygen production and respiration was observed relative to the control, with rates representing less than 5% of the control after 72 h of incubation. A decrease of microbial activities was followed by a decrease of the coupling between autotrophs and heterotrophs. In contrast, in autumn 2012, no significant changes for oxygen production and respiration were observed and the coupling between autotrophs and heterotrophs was not altered. The differences observed between the spring and autumn mats might be explained by the maturity of the microbial mat with dominance of heterotrophic bacteria in spring, and diatoms and cyanobacteria in autumn, as well as by the differences in the chemical composition of the complex mixture of PAHs and metals.
Collapse
Affiliation(s)
- Olivier Pringault
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugène Bataillon, case 093, 34095 Montpellier cedex 5, France
| | - Johanne Aube
- Equipe Environnement et Microbiologie, UMR IPREM 5254, IBEAS BP 1155, Université de Pau et des Pays de l'Adour, 64013 Pau cedex, France
| | - Olivier Bouchez
- Plateforme Génomique Campus INRA, 24 chemin de borde rouge, 31326 Castanet-Tolosan Cedex, France
| | - Christophe Klopp
- Plateforme Génomique Campus INRA, 24 chemin de borde rouge, 31326 Castanet-Tolosan Cedex, France
| | - Jérome Mariette
- Plateforme Génomique Campus INRA, 24 chemin de borde rouge, 31326 Castanet-Tolosan Cedex, France
| | - Frédéric Escudie
- Plateforme Génomique Campus INRA, 24 chemin de borde rouge, 31326 Castanet-Tolosan Cedex, France
| | - Pavel Senin
- Plateforme Génomique Campus INRA, 24 chemin de borde rouge, 31326 Castanet-Tolosan Cedex, France
| | - Marisol Goni-Urriza
- Equipe Environnement et Microbiologie, UMR IPREM 5254, IBEAS BP 1155, Université de Pau et des Pays de l'Adour, 64013 Pau cedex, France
| |
Collapse
|
26
|
Sieczko A, Maschek M, Peduzzi P. Algal extracellular release in river-floodplain dissolved organic matter: response of extracellular enzymatic activity during a post-flood period. Front Microbiol 2015; 6:80. [PMID: 25741326 PMCID: PMC4330910 DOI: 10.3389/fmicb.2015.00080] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 01/22/2015] [Indexed: 11/13/2022] Open
Abstract
River-floodplain systems are susceptible to rapid hydrological events. Changing hydrological connectivity of the floodplain generates a broad range of conditions, from lentic to lotic. This creates a mixture of allochthonously and autochthonously derived dissolved organic matter (DOM). Autochthonous DOM, including photosynthetic extracellular release (PER), is an important source supporting bacterial secondary production (BSP). Nonetheless, no details are available regarding microbial extracellular enzymatic activity (EEA) as a response to PER under variable hydrological settings in river-floodplain systems. To investigate the relationship between bacterial and phytoplankton components, we therefore used EEA as a tool to track the microbial response to non-chromophoric, but reactive and ecologically important DOM. The study was conducted in three floodplain subsystems with distinct hydrological regimes (Danube Floodplain National Park, Austria). The focus was on the post-flood period. Enhanced %PER (up to 48% of primary production) in a hydrologically isolated subsystem was strongly correlated with β-glucosidase, which was related to BSP. This shows that-in disconnected floodplain backwaters with high terrestrial input-BSP can also be driven by autochthonous carbon sources (PER). In a semi-isolated section, in the presence of fresh labile material from primary producers, enhanced activity of phenol oxidase was observed. In frequently flooded river-floodplain systems, BSP was mainly driven by enzymatic degradation of particulate primary production. Our research demonstrates that EEA measurements are an excellent tool to describe the coupling between bacteria and phytoplankton, which cannot be deciphered when focusing solely on chromophoric DOM.
Collapse
Affiliation(s)
- Anna Sieczko
- Department of Limnology and Bio-Oceanography, Inland Water Microbial and Viral Ecology, University of Vienna Vienna, Austria
| | - Maria Maschek
- Department of Limnology and Bio-Oceanography, Inland Water Microbial and Viral Ecology, University of Vienna Vienna, Austria
| | - Peter Peduzzi
- Department of Limnology and Bio-Oceanography, Inland Water Microbial and Viral Ecology, University of Vienna Vienna, Austria
| |
Collapse
|
27
|
Borges AV, Morana C, Bouillon S, Servais P, Descy JP, Darchambeau F. Carbon cycling of Lake Kivu (East Africa): net autotrophy in the epilimnion and emission of CO2 to the atmosphere sustained by geogenic inputs. PLoS One 2014; 9:e109500. [PMID: 25314144 PMCID: PMC4196920 DOI: 10.1371/journal.pone.0109500] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 09/11/2014] [Indexed: 11/19/2022] Open
Abstract
We report organic and inorganic carbon distributions and fluxes in a large (>2000 km2) oligotrophic, tropical lake (Lake Kivu, East Africa), acquired during four field surveys, that captured the seasonal variations (March 2007-mid rainy season, September 2007-late dry season, June 2008-early dry season, and April 2009-late rainy season). The partial pressure of CO2 (pCO2) in surface waters of the main basin of Lake Kivu showed modest spatial (coefficient of variation between 3% and 6%), and seasonal variations with an amplitude of 163 ppm (between 579±23 ppm on average in March 2007 and 742±28 ppm on average in September 2007). The most prominent spatial feature of the pCO2 distribution was the very high pCO2 values in Kabuno Bay (a small sub-basin with little connection to the main lake) ranging between 11,213 ppm and 14,213 ppm (between 18 and 26 times higher than in the main basin). Surface waters of the main basin of Lake Kivu were a net source of CO2 to the atmosphere at an average rate of 10.8 mmol m(-2) d(-1), which is lower than the global average reported for freshwater, saline, and volcanic lakes. In Kabuno Bay, the CO2 emission to the atmosphere was on average 500.7 mmol m(-2) d(-1) (∼46 times higher than in the main basin). Based on whole-lake mass balance of dissolved inorganic carbon (DIC) bulk concentrations and of its stable carbon isotope composition, we show that the epilimnion of Lake Kivu was net autotrophic. This is due to the modest river inputs of organic carbon owing to the small ratio of catchment area to lake surface area (2.15). The carbon budget implies that the CO2 emission to the atmosphere must be sustained by DIC inputs of geogenic origin from deep geothermal springs.
Collapse
Affiliation(s)
- Alberto V. Borges
- Chemical Oceanography Unit, Université de Liège, Liège, Belgium
- * E-mail:
| | - Cédric Morana
- Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
| | - Steven Bouillon
- Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
| | - Pierre Servais
- Ecologie des Systèmes Aquatiques, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Jean-Pierre Descy
- Research Unit in Environmental and Evolutionary Biology, University of Namur, Namur, Belgium
| | | |
Collapse
|
28
|
Mini-review: A priori considerations for bacteria–algae interactions in algal biofuel systems receiving municipal wastewaters. ALGAL RES 2014. [DOI: 10.1016/j.algal.2013.11.009] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
29
|
Fouilland E, Tolosa I, Bonnet D, Bouvier C, Bouvier T, Bouvy M, Got P, Le Floc'h E, Mostajir B, Roques C, Sempéré R, Sime-Ngando T, Vidussi F. Bacterial carbon dependence on freshly produced phytoplankton exudates under different nutrient availability and grazing pressure conditions in coastal marine waters. FEMS Microbiol Ecol 2013; 87:757-69. [DOI: 10.1111/1574-6941.12262] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Eric Fouilland
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Station Méditerranéenne de l'Environnement Littoral; Sète France
- Université Montpellier 2; Montpellier France
| | - Imma Tolosa
- International Atomic Energy Agency- Environment Laboratories; Monaco Monaco
| | - Delphine Bonnet
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
| | - Corinne Bouvier
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
| | - Thierry Bouvier
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
| | - Marc Bouvy
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
| | - Patrice Got
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
| | - Emilie Le Floc'h
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Station Méditerranéenne de l'Environnement Littoral; Sète France
- Université Montpellier 2; Montpellier France
- Centre d'écologie marine expérimentale MEDIMEER (Mediterranean Center for Marine Ecosystem Experimental Research) UMS 3301 (Université Montpellier 2, CNRS); Station Méditerranéenne de l'Environnement Littoral; Sète France
| | - Behzad Mostajir
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
- Centre d'écologie marine expérimentale MEDIMEER (Mediterranean Center for Marine Ecosystem Experimental Research) UMS 3301 (Université Montpellier 2, CNRS); Station Méditerranéenne de l'Environnement Littoral; Sète France
| | - Cécile Roques
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
| | - Richard Sempéré
- Aix-Marseille Université; Université du Sud Toulon-Var; CNRS/INSU, IRD; Mediterranean Institute of Oceanography (MIO) UM 110; Marseille France
| | - Télesphore Sime-Ngando
- Laboratoire Microorganismes: Génome et Environnement (LMGE); UMR CNRS 6023; Clermont Université Blaise Pascal; Aubière France
| | - Francesca Vidussi
- Ecologie des Systèmes Marins côtiers UMR 5119 ECOSYM (Université Montpellier 2, CNRS, IRD, IFREMER, Université Montpellier 1); Sète France
- Université Montpellier 2; Montpellier France
| |
Collapse
|
30
|
Cavalcanti GS, Gregoracci GB, dos Santos EO, Silveira CB, Meirelles PM, Longo L, Gotoh K, Nakamura S, Iida T, Sawabe T, Rezende CE, Francini-Filho RB, Moura RL, Amado-Filho GM, Thompson FL. Physiologic and metagenomic attributes of the rhodoliths forming the largest CaCO3 bed in the South Atlantic Ocean. ISME JOURNAL 2013; 8:52-62. [PMID: 23985749 DOI: 10.1038/ismej.2013.133] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 06/23/2013] [Accepted: 07/04/2013] [Indexed: 11/09/2022]
Abstract
Rhodoliths are free-living coralline algae (Rhodophyta, Corallinales) that are ecologically important for the functioning of marine environments. They form extensive beds distributed worldwide, providing a habitat and nursery for benthic organisms and space for fisheries, and are an important source of calcium carbonate. The Abrolhos Bank, off eastern Brazil, harbors the world's largest continuous rhodolith bed (of ∼21,000 km(2)) and has one of the largest marine CaCO3 deposits (producing 25 megatons of CaCO3 per year). Nevertheless, there is a lack of information about the microbial diversity, photosynthetic potential and ecological interactions within the rhodolith holobiont. Herein, we performed an ecophysiologic and metagenomic analysis of the Abrolhos rhodoliths to understand their microbial composition and functional components. Rhodoliths contained a specific microbiome that displayed a significant enrichment in aerobic ammonia-oxidizing betaproteobacteria and dissimilative sulfate-reducing deltaproteobacteria. We also observed a significant contribution of bacterial guilds (that is, photolithoautotrophs, anaerobic heterotrophs, sulfide oxidizers, anoxygenic phototrophs and methanogens) in the rhodolith metagenome, suggested to have important roles in biomineralization. The increased hits in aromatic compounds, fatty acid and secondary metabolism subsystems hint at an important chemically mediated interaction in which a functional job partition among eukaryal, archaeal and bacterial groups allows the rhodolith holobiont to thrive in the global ocean. High rates of photosynthesis were measured for Abrolhos rhodoliths (52.16 μmol carbon m(-2 )s(-1)), allowing the entire Abrolhos rhodolith bed to produce 5.65 × 10(5) tons C per day. This estimate illustrates the great importance of the Abrolhos rhodolith beds for dissolved carbon production in the South Atlantic Ocean.
Collapse
Affiliation(s)
- Giselle S Cavalcanti
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Gustavo B Gregoracci
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Eidy O dos Santos
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Cynthia B Silveira
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Pedro M Meirelles
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Leila Longo
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Kazuyoshi Gotoh
- Laboratory of Genomic Research on Pathogenic Bacteria, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Shota Nakamura
- Laboratory of Genomic Research on Pathogenic Bacteria, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Tetsuya Iida
- Laboratory of Genomic Research on Pathogenic Bacteria, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Tomoo Sawabe
- Laboratory of Microbiology, Hokkaido University, Sapporo, Japan
| | - Carlos E Rezende
- Environmental Science Laboratory, Campos dos Goytacazes, UENF, Rio de Janeiro, Brazil
| | | | - Rodrigo L Moura
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | | | - Fabiano L Thompson
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| |
Collapse
|
31
|
Gradients in microbial methanol uptake: productive coastal upwelling waters to oligotrophic gyres in the Atlantic Ocean. ISME JOURNAL 2012. [PMID: 23178665 DOI: 10.1038/ismej.2012.130] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Methanol biogeochemistry and its importance as a carbon source in seawater is relatively unexplored. We report the first microbial methanol carbon assimilation rates (k) in productive coastal upwelling waters of up to 0.117±0.002 d(-1) (~10 nmol l(-1 )d(-1)). On average, coastal upwelling waters were 11 times greater than open ocean northern temperate (NT) waters, eight times greater than gyre waters and four times greater than equatorial upwelling (EU) waters; suggesting that all upwelling waters upon reaching the surface (≤20 m), contain a microbial population that uses a relatively high amount of carbon (0.3-10 nmol l(-1 )d(-1)), derived from methanol, to support their growth. In open ocean Atlantic regions, microbial uptake of methanol into biomass was significantly lower, ranging between 0.04-0.68 nmol l(-1 )d(-1). Microbes in the Mauritanian coastal upwelling used up to 57% of the total methanol for assimilation of the carbon into cells, compared with an average of 12% in the EU, and 1% in NT and gyre waters. Several methylotrophic bacterial species were identified from open ocean Atlantic waters using PCR amplification of mxaF encoding methanol dehydrogenase, the key enzyme in bacterial methanol oxidation. These included Methylophaga sp., Burkholderiales sp., Methylococcaceae sp., Ancylobacter aquaticus, Paracoccus denitrificans, Methylophilus methylotrophus, Methylobacterium oryzae, Hyphomicrobium sp. and Methylosulfonomonas methylovora. Statistically significant correlations for upwelling waters between methanol uptake into cells and both chlorophyll a concentrations and methanol oxidation rates suggest that remotely sensed chlorophyll a images, in these productive areas, could be used to derive total methanol biological loss rates, a useful tool for atmospheric and marine climatically active gas modellers, and air-sea exchange scientists.
Collapse
|
32
|
Regional variation in lytic and lysogenic viral infection in the Southern Ocean and its contribution to biogeochemical cycling. Appl Environ Microbiol 2012; 78:6741-8. [PMID: 22798377 DOI: 10.1128/aem.01388-12] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lytic and lysogenic viral infection was investigated throughout the Southern Ocean at sites spanning the sub-Antarctic zone, the Antarctic Circumpolar Current, and an Antarctic continental sea. Higher lytic virus activity was recorded in the more productive sub-Antarctic zone than in the iron-limited waters of the Antarctic Circumpolar Current during two transects. Reduced lytic viral activity in the Antarctic Circumpolar Current was combined with a shift toward lysogenic infection, probably resulting from the lower concentration of potential prokaryotic hosts. Superimposed on this variation, lytic viral production was lower in a transect completed in the Drake Passage in autumn (1.8 × 10(8) to 1.5 × 10(9) liter(-1) day(-1)) than over the Greenwich Meridian during summer (5.1 × 10(8) to 2.0 × 10(10) cells liter(-1) day(-1)), indicating that viral activity is linked to the overall seasonal fluctuations in biotic activity. Interestingly, while prokaryotic abundance was lowest in the coastal Weddell Sea, levels of bacterial and lytic viral production (4.3 × 10(8) to 1.7 × 10(10) cells liter(-1) day(-1)) in this area were similar to those of the other zones. This may explain the weak relationship between the distribution of prokaryotes and chlorophyll in the Weddell Sea, as a high turnover of prokaryotic biomass may have been stimulated by the availability of substrates in the form of viral lysate. With estimated carbon and iron releases of 0.02 to 7.5 μg liter(-1) day(-1) and 1.5 to 175.7 pg liter(-1) day(-1), respectively, viral activity in the Southern Ocean is shown to be a major contributor to satisfying the elemental requirements of microbes, notably prokaryotes in the Weddell Sea and phytoplankton in the sub-Antarctic zone.
Collapse
|
33
|
Variability of the microbial community in the western Antarctic Peninsula from late fall to spring during a low ice cover year. Polar Biol 2010. [DOI: 10.1007/s00300-010-0806-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
34
|
Fouilland E, Mostajir B. Revisited phytoplanktonic carbon dependency of heterotrophic bacteria in freshwaters, transitional, coastal and oceanic waters. FEMS Microbiol Ecol 2010; 73:419-29. [DOI: 10.1111/j.1574-6941.2010.00896.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
35
|
Pugnetti A, Del Negro P, Giani M, Acri F, Aubry FB, Bianchi F, Berto D, Valeri A. Phytoplankton-bacterioplankton interactions and carbon fluxes through microbial communities in a microtidal lagoon. FEMS Microbiol Ecol 2010; 72:153-64. [DOI: 10.1111/j.1574-6941.2010.00839.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
36
|
Tai V, Paulsen IT, Phillippy K, Johnson DA, Palenik B. Whole-genome microarray analyses of Synechococcus-Vibrio interactions. Environ Microbiol 2009; 11:2698-709. [PMID: 19659554 DOI: 10.1111/j.1462-2920.2009.01997.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Microbes live in diverse communities yet their physiologies are typically studied in axenic culture. To begin to address this dichotomy, whole-genome microarray analyses were used and revealed that several major metabolic pathways were affected in Synechococcus sp. WH8102, a model phototroph, when grown with Vibrio parahaemolyticus, a model heterotroph. In co-cultures with V. parahaemolyticus, although phosphate was not depleted, Synechococcus sp. WH8102 may have experienced phosphate stress since the expression of phosphate acquisition genes increased and alkaline phosphatase activity was higher than in monocultures. Expression of cell wall synthesis genes and the components of a zinc transporter were also upregulated. In contrast, a ferric uptake regulation (Fur) family gene was downregulated as were genes that encode proteins rich in iron or involved in detoxifying oxygen radicals. Nitrogen use may also have been affected in co-cultures as the gene expression changes share similarities with ammonia-grown Synechococcus. This study demonstrates the multiple impacts that interspecific microbial interactions can have on the physiology of a major primary producer and the importance of investigating microbial physiology from a community perspective.
Collapse
Affiliation(s)
- Vera Tai
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California - San Diego, La Jolla, CA 92093-0202, USA
| | | | | | | | | |
Collapse
|
37
|
Levy JL, Stauber JL, Wakelin SA, Jolley DF. The effect of bacteria on the sensitivity of microalgae to copper in laboratory bioassays. CHEMOSPHERE 2009; 74:1266-1274. [PMID: 19101014 DOI: 10.1016/j.chemosphere.2008.10.049] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 10/22/2008] [Accepted: 10/27/2008] [Indexed: 05/27/2023]
Abstract
Although single-species laboratory toxicity tests with microalgae are sensitive and highly reproducible, they lack environmental realism. Interactions between algae and their associated bacteria, either in the plankton or in biofilms, may alter algal sensitivity to contaminants, which are not mimicked in laboratory toxicity tests. This study investigated the effects of simple algal-bacterial relationships on the sensitivity of laboratory-cultured algae to copper using 72-h algal growth-rate inhibition bioassays. Four species of microalgae were used, two isolates of each; a strain of algae with no microscopically visible and no culturable bacteria present (operationally defined as axenic) and a non-axenic strain. The four algae used were the marine diatom Nitzschia closterium, the freshwater green alga Pseudokirchneriella subcapitata and two tropical Chlorella spp. Under control conditions (no copper), N. closterium and P. subcapitata grew better in the presence of the bacterial community. Sensitivity to copper (assessed as the concentration to inhibit the growth rate by 50% after 72-h (IC50)) was not significantly different for the axenic and non-axenic strains of N. closterium, P. subcapitata or for Chlorella sp. (PNG isolate). At pH 5.7, the axenic Chlorella sp. (NT isolate) had a 72-h IC50 of 46mugCuL(-1), while in the presence of bacteria the IC50 increased (i.e., sensitivity decreased) to 208mugCuL(-1). However, when the bacterial status of both the operationally defined axenic and non-axenic cultures of N. closterium and Chlorella sp. (NT isolate) was investigated using polymerase chain reaction (PCR) amplification of 16S rRNA followed by DNA fingerprinting using denaturing gradient gel electrophoresis (DGGE), it was found that bacteria were actually present in all the algal cultures, i.e. the axenic cultures were not truly bacteria-free. Based on sequence information, the bacteria present were nearly all identified as alphaproteobacteria, and a number of isolates had high similarity to bacteria previously identified as symbionts or species endophytically associated with marine organisms. The "axenic" cultures contained less bacterial phylotypes than the non-axenic cultures, and based on band-intensity, also contained less bacterial DNA. This supported the findings of few differences in copper sensitivity between strains, and suggests that standard microalgal toxicity tests probably inadvertently use non-axenic cultures in metal assessment.
Collapse
Affiliation(s)
- Jacqueline L Levy
- Centre for Environmental Contaminants Research, CSIRO Land and Water, Private Mailbag 7, Lucas Heights, NSW 2234, Australia.
| | | | | | | |
Collapse
|
38
|
Pringault O, Tesson S, Rochelle-Newall E. Respiration in the light and bacterio-phytoplankton coupling in a coastal environment. MICROBIAL ECOLOGY 2009; 57:321-334. [PMID: 18661115 DOI: 10.1007/s00248-008-9422-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Accepted: 06/12/2008] [Indexed: 05/26/2023]
Abstract
In pelagic ecosystems, the principal source of organic matter is via autotrophic production and the primary sink is through heterotrophic respiration. One would therefore anticipate that there is some degree of linkage between these two compartments. Recent work has shown that respiration in the light is higher than dark respiration. Consequently, many of the methods used to determine respiration and production are biased as they require the assumption that light and dark respiration rates are equivalent. We show here that, in a coastal ecosystem, under visible light exposure, respiration in the light is related to gross production. More than 60% of the variation of respiration in the light, measured at 1 to 40 microg L(-1) of chlorophyll a (Chla), could be explained by the variations of gross production. Secondly, the relative contribution of bacterial respiration to community respiration in the light represented up to 79% at low Chla (1 microg L(-1)) and was negatively correlated with Chla concentration. Although bacterial production and bacterial respiration were both enhanced in the light, bacterial respiration in the light was more stimulated than bacterial production, which resulted in a decrease in bacterial growth efficiency during light exposure. These results show that the impact of light on the functioning of the microbial loop needs to be taken into account for a better understanding of the oceanic carbon cycle.
Collapse
Affiliation(s)
- Olivier Pringault
- UR 103 CAMELIA, Centre IRD de Nouméa, BP A5 98848, Nouméa, New Caledonia, France.
| | | | | |
Collapse
|
39
|
López-Urrutia A, Morán XAG. Resource limitation of bacterial production distorts the temperature dependence of oceanic carbon cycling. Ecology 2007; 88:817-22. [PMID: 17536698 DOI: 10.1890/06-1641] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Our view of the effects of temperature on bacterial carbon fluxes in the ocean has been confounded by the interplay of resource availability. Using an extensive compilation of cell-specific bacterial respiration (BRi) and production (BPi), we show that both physiological rates respond to changing temperature in a similar manner and follow the predictions of the metabolic theory of ecology. Their apparently different temperature dependence under warm, oligotrophic conditions is due to strong resource limitation of BP, but not of BRi. Thus, and despite previous preconception, bacterial growth efficiency (BGE = BPi/[BPi + BRi]) is not directly regulated by temperature, but by the availability of substrates for growth. We develop simple equations that can be used for the estimation of bacterial community metabolism from temperature, chlorophyll concentration, and bacterial abundance. Since bacteria are the greatest living planktonic biomass, our results challenge current understanding of how warming and shifts in ecosystem trophic state will modify oceanic carbon cycle feedbacks to climate change.
Collapse
Affiliation(s)
- Angel López-Urrutia
- Centro Oceanográfico de Gijón, Instituto Español de Oceanografía, Camín de L'Arbeyal, s/n, Xixón, Asturies, E-33212 Spain.
| | | |
Collapse
|
40
|
Ducklow HW, Baker K, Martinson DG, Quetin LB, Ross RM, Smith RC, Stammerjohn SE, Vernet M, Fraser W. Marine pelagic ecosystems: the west Antarctic Peninsula. Philos Trans R Soc Lond B Biol Sci 2007; 362:67-94. [PMID: 17405208 PMCID: PMC1764834 DOI: 10.1098/rstb.2006.1955] [Citation(s) in RCA: 195] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The marine ecosystem of the West Antarctic Peninsula (WAP) extends from the Bellingshausen Sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. The glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. The ecosystem is divided into three subregions, the continental slope, shelf and coastal regions, each with unique ocean dynamics, water mass and biological distributions. The WAP shelf lies within the Antarctic Sea Ice Zone (SIZ) and like other SIZs, the WAP system is very productive, supporting large stocks of marine mammals, birds and the Antarctic krill, Euphausia superba. Ecosystem dynamics is dominated by the seasonal and interannual variation in sea ice extent and retreat. The Antarctic Peninsula is one among the most rapidly warming regions on Earth, having experienced a 2 degrees C increase in the annual mean temperature and a 6 degrees C rise in the mean winter temperature since 1950. Delivery of heat from the Antarctic Circumpolar Current has increased significantly in the past decade, sufficient to drive to a 0.6 degrees C warming of the upper 300 m of shelf water. In the past 50 years and continuing in the twenty-first century, the warm, moist maritime climate of the northern WAP has been migrating south, displacing the once dominant cold, dry continental Antarctic climate and causing multi-level responses in the marine ecosystem. Ecosystem responses to the regional warming include increased heat transport, decreased sea ice extent and duration, local declines in icedependent Adélie penguins, increase in ice-tolerant gentoo and chinstrap penguins, alterations in phytoplankton and zooplankton community composition and changes in krill recruitment, abundance and availability to predators. The climate/ecological gradients extending along the WAP and the presence of monitoring systems, field stations and long-term research programmes make the region an invaluable observatory of climate change and marine ecosystem response.
Collapse
Affiliation(s)
- Hugh W Ducklow
- School of Marine Science, The College of William and Mary, Gloucester Point, VA 23062, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Chapter 10 Pelagic Bacterial Processes in Polynyas. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0422-9894(06)74010-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
|
42
|
Varela MM, Bode A, Morán XAG, Valencia J. Dissolved organic nitrogen release and bacterial activity in the upper layers of the Atlantic Ocean. MICROBIAL ECOLOGY 2006; 51:487-500. [PMID: 16645924 DOI: 10.1007/s00248-006-9054-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2005] [Accepted: 11/11/2005] [Indexed: 05/08/2023]
Abstract
The variability of the percentage of extracellular dissolved organic nitrogen (DON) release (PER), along with the relationship between DON release and bacterioplankton activity, was examined during five oceanographic cruises, carried out in the upwelling region of the NW Iberian Peninsula, the SW Bay of Biscay, and a latitudinal transect in the Atlantic Ocean (50 degrees N-35 degrees S). Rates of nitrogen uptake, DON release, and bacterial production were measured at 66 stations and sampled between August 1998 and October 2000. The percentage of DON release relative to the gross uptake of ammonium (PERNH4+) ranged from 3 to 46%, whereas that relative to total nitrogen (NH4+ + NO3- + urea) gross uptake (PERtotal) varied between 21 and 82%. The highest values for both PERNH4+ and PER(total) were found in oligotrophic oceanic waters (< 0.25 mg chlorophyll a m(-3)). In oceanic environments, a positive relationship was found between nitrogen uptake and DON release rates, with a log-log linear regression slope significantly lower than 1, suggesting an inverse relationship between PER and gross nitrogen uptake rates. In contrast, in areas with higher productivity levels (> 6 mg chlorophyll a m(-3)), such as the continental shelf off the NW Iberian Peninsula, PER held constant as nitrogen uptake increased. These results suggest the dominance of different processes controlling DON release in oceanic and neritic zones. DON release rates accounted for less than 15% of the variability observed in bacterial production rates, suggesting a weak response of bacterioplankton to phytoplankton on short time scales (hours). Furthermore, nitrogen budgets showed an excess of DON release in relation to bacterial requirements.
Collapse
Affiliation(s)
- Marta M Varela
- Instituto Español de Oceanografía, Centro Oceanográfico de A Coruña, Apdo. 130, 15080-A, Coruña, Spain.
| | | | | | | |
Collapse
|
43
|
Mueller LN, de Brouwer JFC, Almeida JS, Stal LJ, Xavier JB. Analysis of a marine phototrophic biofilm by confocal laser scanning microscopy using the new image quantification software PHLIP. BMC Ecol 2006; 6:1. [PMID: 16412253 PMCID: PMC1360661 DOI: 10.1186/1472-6785-6-1] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Accepted: 01/16/2006] [Indexed: 11/15/2022] Open
Abstract
Background Confocal laser scanning microscopy (CLSM) is the method of choice to study interfacial biofilms and acquires time-resolved three-dimensional data of the biofilm structure. CLSM can be used in a multi-channel modus where the different channels map individual biofilm components. This communication presents a novel image quantification tool, PHLIP, for the quantitative analysis of large amounts of multichannel CLSM data in an automated way. PHLIP can be freely downloaded from Results PHLIP is an open source public license Matlab toolbox that includes functions for CLSM imaging data handling and ten image analysis operations describing various aspects of biofilm morphology. The use of PHLIP is here demonstrated by a study of the development of a natural marine phototrophic biofilm. It is shown how the examination of the individual biofilm components using the multi-channel capability of PHLIP allowed the description of the dynamic spatial and temporal separation of diatoms, bacteria and organic and inorganic matter during the shift from a bacteria-dominated to a diatom-dominated phototrophic biofilm. Reflection images and weight measurements complementing the PHLIP analyses suggest that a large part of the biofilm mass consisted of inorganic mineral material. Conclusion The presented case study reveals new insight into the temporal development of a phototrophic biofilm where multi-channel imaging allowed to parallel monitor the dynamics of the individual biofilm components over time. This application of PHLIP presents the power of biofilm image analysis by multi-channel CLSM software and demonstrates the importance of PHLIP for the scientific community as a flexible and extendable image analysis platform for automated image processing.
Collapse
Affiliation(s)
- Lukas N Mueller
- Institute for Molecular Systems Biology, ETH Hönggerberg, CH-8093 Zürich, Switzerland
- Instituto de Tecnologia de Quimíca e Biológica, Universidade Nova de Lisboa, 2781-901 Oeiras, Portugal
| | - Jody FC de Brouwer
- Scottish Association for Marine Science, Oban, Argyll, Scotland, PA37 1QA, UK
| | - Jonas S Almeida
- Instituto de Tecnologia de Quimíca e Biológica, Universidade Nova de Lisboa, 2781-901 Oeiras, Portugal
- Department of Biostatistics, Bioinformatics and Epidemiology, Medical University of South Carolina, Charleston SC 29425, USA
| | - Lucas J Stal
- Center for Estuarine and Marine Ecology, Netherlands Institute of Ecology (NIOO-KNAW), PO Box 140, 440 0 AC Yerseke, The Netherlands
| | - João B Xavier
- Department of Biotechnology, Delft University of Technology, 2628 BC Delft, The Netherlands
| |
Collapse
|
44
|
Grégori G, Denis M, Lefèvre D, Romano JC. Viabilité des bactéries hétérotrophes dans la baie de Marseille. C R Biol 2003; 326:739-50. [PMID: 14608694 DOI: 10.1016/j.crvi.2003.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Marine microorganism activities are commonly assessed by bulk methods and assigned to the total cell count. The presence in significant amounts of ghost, dead, and damaged cells makes such as assignment a non-correct one. A Nucleic Acid Double Staining protocol (NADS) of fresh water bacteria (Barbesti et al., Cytometry 40 (2000) 214-218) has been adapted to resolve viable, damaged and dead cells in marine environments (Grégori et al., Appl. Environ. Microbiol. 67 (2001) 4662-4670). The present reports the first in situ application of this approach, conducted in the Bay of Marseilles in winter and spring periods at two sites with contrasted features.
Collapse
Affiliation(s)
- Gérald Grégori
- Purdue University Cytometry Laboratories, Hansen Life Sciences Research Building, Room B050, 201 S. University Street, West Lafayette, IN 47907-2064, USA
| | | | | | | |
Collapse
|