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Ortmann AC, Cobanli SE, Wohlgeschaffen G, Poon HY, Ryther C, Greer CW, Wasserscheid J, Elias M, Robinson B, King TL. Factors that affect water column hydrocarbon concentrations have minor impacts on microbial responses following simulated diesel fuel spills. MARINE POLLUTION BULLETIN 2023; 194:115358. [PMID: 37567129 DOI: 10.1016/j.marpolbul.2023.115358] [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: 02/01/2023] [Revised: 07/24/2023] [Accepted: 07/29/2023] [Indexed: 08/13/2023]
Abstract
Effects of season and mixing on hydrocarbon concentrations and the microbial community response was explored in a series of mesocosm experiments simulating surface spills of diesel into coastal waters. Mixing of any amount contributed to hydrocarbons entering the water column, but diesel fuel composition had a significant effect on hydrocarbon concentrations. Higher initial concentrations of aromatic hydrocarbons resulted in higher water column concentrations, with minimal differences among seasons due to high variability. Regardless of the concentrations of hydrocarbons, prokaryotes increased and there were higher relative abundances of hydrocarbon affiliated bacteria with indications of biodegradation within 4 d of exposure. As concentrations decreased over time, the eukaryote community shifted from the initial community to one which appeared to be composed of organisms with some resilience to hydrocarbons. This series of experiments demonstrates the wide range of conditions under which natural attenuation of diesel fuel is an effective response.
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Affiliation(s)
- Alice C Ortmann
- Centre for Offshore Oil, Gas and Energy Research, Fisheries and Oceans Canada, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada.
| | - Susan E Cobanli
- Centre for Offshore Oil, Gas and Energy Research, Fisheries and Oceans Canada, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada
| | - Gary Wohlgeschaffen
- Centre for Offshore Oil, Gas and Energy Research, Fisheries and Oceans Canada, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada
| | - Ho Yin Poon
- Centre for Offshore Oil, Gas and Energy Research, Fisheries and Oceans Canada, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada
| | - Camilla Ryther
- Dalhousie University, 6299 South Street, Halifax, NS B3H 4R2, Canada
| | - Charles W Greer
- National Research Council of Canada, Energy, Mining and Environment Research Centre, 6100 Royalmount Ave, Montreal, PQ H4P 2R2, Canada
| | - Jessica Wasserscheid
- National Research Council of Canada, Energy, Mining and Environment Research Centre, 6100 Royalmount Ave, Montreal, PQ H4P 2R2, Canada
| | - Miria Elias
- National Research Council of Canada, Energy, Mining and Environment Research Centre, 6100 Royalmount Ave, Montreal, PQ H4P 2R2, Canada
| | - Brian Robinson
- Centre for Offshore Oil, Gas and Energy Research, Fisheries and Oceans Canada, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada
| | - Thomas L King
- Centre for Offshore Oil, Gas and Energy Research, Fisheries and Oceans Canada, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada
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Ryther CM, Ortmann AC, Wohlgeschaffen G, Robinson BJ. Temperate Coastal Microbial Communities Rapidly Respond to Low Concentrations of Partially Weathered Diesel. MICROBIAL ECOLOGY 2022; 84:1122-1132. [PMID: 34888738 PMCID: PMC9747835 DOI: 10.1007/s00248-021-01939-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 12/05/2021] [Indexed: 05/23/2023]
Abstract
Diesel is frequently encountered in coastal ecosystems due to land run-off from road surfaces. The current study investigates how partially weathered diesel at environmentally relevant concentrations, as may be seen during a run-off event, affect coastal microbial communities. A mesocosm experiment using seawater from the Bedford Basin, Nova Scotia, was followed for 72 h after the addition of partially weathered diesel. Sequencing data suggests partially weathered diesel acts quickly to alter the prokaryotic community, as both opportunistic (Vibrio and Lentibacter) and oil-degrading (Colwellia, Sulfitobacter, and Pseudoalteromonas) bacteria proliferated after 24 h in comparison to the control. In addition, total prokaryotes seemed to recover in abundance after 24 h, where eukaryotes only ceased to decrease slightly at 72 h, likely because of an inability to adapt to the oil-laden conditions, unlike the prokaryotes. Considering there were no highly volatile components (benzene, toluene, ethylbenzene, and xylene) present in the diesel when the communities were exposed, the results indicate that even a relatively small concentration of diesel run-off can cause a drastic change to the microbial community under low energy conditions. Higher energy conditions due to wave action may mitigate the response of the microbial communities by dilution and additional weathering of the diesel.
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Affiliation(s)
- Camilla M Ryther
- Biology Department, Dalhousie University, 6299 South Street, Halifax, NS, B3H 4R2, Canada
| | - Alice C Ortmann
- Centre for Offshore Oil, Gas and Energy Research Laboratory, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS, B2Y 4A2, Canada.
| | - Gary Wohlgeschaffen
- Centre for Offshore Oil, Gas and Energy Research Laboratory, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS, B2Y 4A2, Canada
| | - Brian J Robinson
- Centre for Offshore Oil, Gas and Energy Research Laboratory, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS, B2Y 4A2, Canada
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3
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Melliti Ben Garali S, Sahraoui I, Ben Othman H, Kouki A, de la Iglesia P, Diogène J, Lafabrie C, Andree KB, Fernández-Tejedor M, Mejri K, Meddeb M, Pringault O, Hlaili AS. Capacity of the potentially toxic diatoms Pseudo-nitzschia mannii and Pseudo-nitzschia hasleana to tolerate polycyclic aromatic hydrocarbons. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 214:112082. [PMID: 33721579 DOI: 10.1016/j.ecoenv.2021.112082] [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: 09/18/2020] [Revised: 02/15/2021] [Accepted: 02/17/2021] [Indexed: 06/12/2023]
Abstract
This study investigates the effects of polycyclic aromatic hydrocarbons (PAHs) on two potentially toxic Pseudo-nitzschia hasleana and P. mannii, isolated from a PAH contaminated marine environment. Both species, maintained in non-axenic cultures, have been exposed during 144 h to increasing concentrations of a 15 PAHs mixture. Analysis of the domoic acid, showed very low concentrations. Dose-response curves for growth and photosynthesis inhibition were determined. Both species have maintained their growth until the end of incubation even at the highest concentration tested (120 µg l-1), Nevertheless, P mannii showed faster growth and seemed to be more tolerant than P. hasleana. To reduce PAH toxicity, both species have enhanced their biovolume, with a higher increase for P. mannii relative to P hasleana. Both species were also capable of bio-concentrating PAHs and were able to degrade them probably in synergy with their associated bacteria. The highest biodegradation was observed for P. mannii, which could harbored more efficient hydrocarbon-degrading bacteria. This study provides the first evidence that PAHs can control the growth and physiology of potentially toxic diatoms. Future studies should investigate the bacterial community associated with Pseudo-nitzschia species, as responses to pollutants or to other environmental stressors could be strongly influence by associated bacteria.
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Affiliation(s)
- Sondes Melliti Ben Garali
- Laboratoire de Biologie Végétale et Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Bizerte, Tunisia; Université de Tunis El Manar, Faculté des Sciences de Tunis, LR18ES41 Sciences de l'Environnement, Biologie et Physiologie des Organismes Aquatiques, Tunis, Tunisia.
| | - Inès Sahraoui
- Laboratoire de Biologie Végétale et Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Bizerte, Tunisia; Université de Tunis El Manar, Faculté des Sciences de Tunis, LR18ES41 Sciences de l'Environnement, Biologie et Physiologie des Organismes Aquatiques, Tunis, Tunisia
| | - Hiba Ben Othman
- Laboratoire de Biologie Végétale et Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Bizerte, Tunisia
| | - Abdessalem Kouki
- Laboratoire de Microscopie électronique et de Microanalyse, Faculté des Sciences de Bizerte, Université de Carthage, Bizerte, Tunisia
| | - Pablo de la Iglesia
- Institut de Recherche et Technologie Agroalimentaire (IRTA), Ctra. Poble Nou, Km 5.5, Sant Carles de la Rapita, 43540 Tarragona, Spain
| | - Jorge Diogène
- Institut de Recherche et Technologie Agroalimentaire (IRTA), Ctra. Poble Nou, Km 5.5, Sant Carles de la Rapita, 43540 Tarragona, Spain
| | - Céline Lafabrie
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugéne Bataillon, Case 093, 34095 Montpellier Cedex 5, France
| | - Karl B Andree
- Institut de Recherche et Technologie Agroalimentaire (IRTA), Ctra. Poble Nou, Km 5.5, Sant Carles de la Rapita, 43540 Tarragona, Spain
| | - Margarita Fernández-Tejedor
- Institut de Recherche et Technologie Agroalimentaire (IRTA), Ctra. Poble Nou, Km 5.5, Sant Carles de la Rapita, 43540 Tarragona, Spain
| | - Kaouther Mejri
- Laboratoire de Biologie Végétale et Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Bizerte, Tunisia; Université de Tunis El Manar, Faculté des Sciences de Tunis, LR18ES41 Sciences de l'Environnement, Biologie et Physiologie des Organismes Aquatiques, Tunis, Tunisia
| | - Marouan Meddeb
- Laboratoire de Biologie Végétale et Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Bizerte, Tunisia; Université de Tunis El Manar, Faculté des Sciences de Tunis, LR18ES41 Sciences de l'Environnement, Biologie et Physiologie des Organismes Aquatiques, Tunis, Tunisia
| | - Olivier Pringault
- UMR 9190 MARBEC IRD-Ifremer-CNRS-Université de Montpellier, Place Eugéne Bataillon, Case 093, 34095 Montpellier Cedex 5, France; UMR 110 MOI Institut Méditerranéen d'Océanologie, UniversitéAix Marseille, Université de Toulon, CNRS, IRD, Marseille, France
| | - Asma Sakka Hlaili
- Laboratoire de Biologie Végétale et Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Bizerte, Tunisia; Université de Tunis El Manar, Faculté des Sciences de Tunis, LR18ES41 Sciences de l'Environnement, Biologie et Physiologie des Organismes Aquatiques, Tunis, Tunisia
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Quigg A, Parsons M, Bargu S, Ozhan K, Daly KL, Chakraborty S, Kamalanathan M, Erdner D, Cosgrove S, Buskey EJ. Marine phytoplankton responses to oil and dispersant exposures: Knowledge gained since the Deepwater Horizon oil spill. MARINE POLLUTION BULLETIN 2021; 164:112074. [PMID: 33540275 DOI: 10.1016/j.marpolbul.2021.112074] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/16/2020] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
The Deepwater Horizon oil spill of 2010 brought the ecology and health of the Gulf of Mexico to the forefront of the public's and scientific community's attention. Not only did we need a better understanding of how this oil spill impacted the Gulf of Mexico ecosystem, but we also needed to apply this knowledge to help assess impacts from perturbations in the region and guide future response actions. Phytoplankton represent the base of the food web in oceanic systems. As such, alterations of the phytoplankton community propagate to upper trophic levels. This review brings together new insights into the influence of oil and dispersant on phytoplankton. We bring together laboratory, mesocosm and field experiments, including insights into novel observations of harmful algal bloom (HAB) forming species and zooplankton as well as bacteria-phytoplankton interactions. We finish by addressing knowledge gaps and highlighting key topics for research in novel areas.
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Affiliation(s)
- Antonietta Quigg
- Texas A&M University at Galveston, 200 Seawolf Parkway, Galveston, TX 77553, USA.
| | - Michael Parsons
- Florida Gulf Coast University, 10501 FGCU Blvd South, Fort Myers, FL 33965, USA.
| | - Sibel Bargu
- Louisiana State University, 1235 Energy, Coast & Environment Building, Baton Rouge, LA 70803, USA.
| | - Koray Ozhan
- Middle East Technical University, P.O. Box 28, 33731 Erdemli, Mersin, Turkey.
| | - Kendra L Daly
- University of South Florida, 140 Seventh Ave S., St. Petersburg, FL 33701, USA.
| | - Sumit Chakraborty
- Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA.
| | - Manoj Kamalanathan
- Texas A&M University at Galveston, 200 Seawolf Parkway, Galveston, TX 77553, USA.
| | - Deana Erdner
- University of Texas Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA.
| | - Sarah Cosgrove
- University of Texas Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA.
| | - Edward J Buskey
- University of Texas Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA.
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Sharma KV, Sarvalingam BK, Marigoudar SR. A review of mesocosm experiments on heavy metals in marine environment and related issues of emerging concerns. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:1304-1316. [PMID: 33079346 DOI: 10.1007/s11356-020-11121-3] [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: 02/07/2020] [Accepted: 10/04/2020] [Indexed: 06/11/2023]
Abstract
Mesocosms are real-world environmental science tools for bridging the gap between laboratory-scale experiments and actual habitat studies on ecosystem complexities. These experiments are increasingly being applied in understanding the complex impacts of heavy metals, ocean acidification, global warming, and oil spills. The insights of the present review indicate how metals and metal-bound activities impact on various aspects of ecological complexities like prey predator cues, growth, embryonic development, and reproduction. Plankton and benthos are used more often over fish and microbes owing to their smaller size, faster reproduction, amenability, and repeatability during mesocosm experiments. The results of ocean acidification reveal calcification of plankton, corals, alteration of pelagic structures, and plankton blooms. The subtle effect of oil spills is amplified on sediment microorganisms, primary producers, and crustaceans. An overview of the mesocosm designs over the years indicates that gradual changes have evolved in the type, size, design, composition, parameters, methodology employed, and the outputs obtained. Most of the pelagic and benthic mesocosm designs involve consideration of interactions within the water columns, between water and sediments, trophic levels, and nutrient rivalry. Mesocosm structures are built considering physical processes (tidal currents, turbulence, inner cycling of nutrients, thermal stratification, and mixing), biological complexities (population, community, and ecosystem) using appropriate filling containers, and sampling facilities that employ inert materials. The principle of design is easy transportation, mooring, deployment, and free floating structures besides addressing the unique ecosystem-based science problems. The evolution of the mesocosm tools helps in understanding further advancement of techniques and their applications in marine ecosystems.
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Affiliation(s)
- Krishna Venkatarama Sharma
- National Centre for Coastal Research, Ministry of Earth Sciences, Government of India, NIOT Campus, Pallikaranai, Chennai, 600 100, India
| | - Barath Kumar Sarvalingam
- National Centre for Coastal Research, Ministry of Earth Sciences, Government of India, NIOT Campus, Pallikaranai, Chennai, 600 100, India
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6
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Ben Othman H, Lanouguère É, Got P, Sakka Hlaili A, Leboulanger C. Structural and functional responses of coastal marine phytoplankton communities to PAH mixtures. CHEMOSPHERE 2018; 209:908-919. [PMID: 30114740 DOI: 10.1016/j.chemosphere.2018.06.153] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 06/13/2018] [Accepted: 06/25/2018] [Indexed: 06/08/2023]
Abstract
The toxicity of polycyclic aromatic hydrocarbons (PAHs) mixtures was evaluated on natural phytoplankton communities sampled from lagoons of Bizerte (South-western Mediterranean Sea) and Thau (North-western Mediterranean Sea). PAHs induced short-term dose and ecosystem-dependant decreases in photosynthetic potential. Chlorophyll a was negatively affected by increasing PAHs concentrations, together with dramatic changes in phytoplankton community composition. Size classes were strongly affected in the Bizerte compare to the Thau lagoon, with a decrease in nano- and microphytoplankton densities compare to picophytoplankton. In both locations, the diatom Entomoneis paludosa appeared favoured under PAH exposure as evidenced by increase in cell density, whereas autotrophic flagellates and dinophytes were strongly reduced. Smaller cells were more tolerant to exposure to highest PAHs concentrations, with persistent picophytoplankton carbon biomass at the end of the incubations. Apparent recovery of photosynthetic potential, accompanied with a regrowth of chlorophyll a under the lowest PAH doses, coincided with a significantly altered community composition in both lagoons. Furthermore, sensitivity to PAHs was not related to the phytoplankton cell size, and toxicity-induced modification of top-down control by grazers during the experiment cannot be excluded.
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Affiliation(s)
- Hiba Ben Othman
- LMI COSYS-MED, UMR 248 MARBEC, IRD-CNRS- Université Montpellier-Ifremer, Avenue Jean Monnet, F-34200 Sète, France; LMI COSYS-MED, Laboratoire de Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Zarzouna 7021, Bizerte, Tunisia.
| | - Élodie Lanouguère
- LMI COSYS-MED, UMR 248 MARBEC, IRD-CNRS- Université Montpellier-Ifremer, Avenue Jean Monnet, F-34200 Sète, France
| | - Patrice Got
- LMI COSYS-MED, UMR 248 MARBEC, IRD-CNRS- Université Montpellier-Ifremer, Avenue Jean Monnet, F-34200 Sète, France
| | - Asma Sakka Hlaili
- LMI COSYS-MED, Laboratoire de Phytoplanctonologie, Faculté des Sciences de Bizerte, Université de Carthage, Zarzouna 7021, Bizerte, Tunisia
| | - Christophe Leboulanger
- LMI COSYS-MED, UMR 248 MARBEC, IRD-CNRS- Université Montpellier-Ifremer, Avenue Jean Monnet, F-34200 Sète, France
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Kottuparambil S, Agusti S. PAHs sensitivity of picophytoplankton populations in the Red Sea. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 239:607-616. [PMID: 29704673 DOI: 10.1016/j.envpol.2018.04.079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/27/2018] [Accepted: 04/18/2018] [Indexed: 06/08/2023]
Abstract
In this study, we investigated the in situ responses of Red Sea picophytoplankton, the dominant phytoplankton group in the oligotrophic ocean, to two toxic polycyclic aromatic hydrocarbons (PAHs), phenanthrene and pyrene. The experiments were conducted across a latitudinal gradient of the Saudi Arabian Red Sea, an area sensitive to oil pollution. We observed significant adverse effects on the growth and abundance of the picocyanobacteria Synechococcus and picoeukaryotes, at all stations sampled. Prochlorococcus, which was abundant only at one of the stations, also appeared to be affected. Pyrene was found to be more toxic to phytoplankton at all stations. In general, picoeukaryotes exhibited higher sensitivity to PAHs than Synechococcus. Populations in the highly oligotrophic Northern region of the Red Sea were more tolerant to PAHs, presumably influenced by the natural selection of more resistant strains of phytoplankton due to the prolonged exposure to PAHs. Toxicity threshold values estimated here are higher than those reported for picophytoplankton from other oligotrophic marine waters and exceed by far the natural levels of PAHs in many oceans. Our findings reveal a possible adaptation of picophytoplankton populations to oil-related contaminants, which may clearly influence their spatial distribution patterns in the Red Sea.
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Affiliation(s)
- Sreejith Kottuparambil
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
| | - Susana Agusti
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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Ramadass K, Megharaj M, Venkateswarlu K, Naidu R. Toxicity of diesel water accommodated fraction toward microalgae, Pseudokirchneriella subcapitata and Chlorella sp. MM3. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2017; 142:538-543. [PMID: 28478380 DOI: 10.1016/j.ecoenv.2017.04.052] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 04/20/2017] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
Diesel is a commonly used fuel and a key pollutant on water surface through leaks and accidental spills, thus creating risk directly to planktons as well as other aquatic organisms. We assessed the toxicty of diesel and its water accommodated fraction (WAF) towards two microalgal species, Pseudokirchneriella subcapitata and Chlorella sp. MM3. The toxicity criteria included were: chlorophyll a content as a growth parameter and induction of enzyme activities linked to oxidative stress. Increase in concentrations of diesel or its WAF significantly increased toxicity towards growth, measured in terms of chlorophyll a content in both the algae. Activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) in response to addition of diesel or diesel WAF to the microalgal cultures were dose-dependent. Diesel WAF was more toxic than diesel itself, suggesting that use of WAF may be more relevant for environmental risk assessment of diesel. The overall response of the antioxidant enzymes to toxicants' stress followed the order: POX≥SOD>CAT. The present study clearly demonstrated the use of SOD, POX and CAT as suitable biomarkers for assessing diesel pollution in aquatic ecosystem.
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Affiliation(s)
- Kavitha Ramadass
- Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation (GCER) and Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRCCARE), Faculty of Science, University of Newcastle, ATC Building, Callaghan, NSW 2308, Australia.
| | - Kadiyala Venkateswarlu
- Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia; Formerly Department of Microbiology, Sri Krishnadevaraya University, Anantapur 515055, India
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER) and Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRCCARE), Faculty of Science, University of Newcastle, ATC Building, Callaghan, NSW 2308, Australia
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9
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State of the art on public risk assessment of combined human exposure to multiple chemical contaminants. Trends Food Sci Technol 2016. [DOI: 10.1016/j.tifs.2016.06.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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10
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Blinova I, Kanarbik L, Sihtmäe M, Kahru A. Toxicity of Water Accommodated Fractions of Estonian Shale Fuel Oils to Aquatic Organisms. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 70:383-391. [PMID: 26590906 DOI: 10.1007/s00244-015-0242-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 11/13/2015] [Indexed: 06/05/2023]
Abstract
Estonia is the worldwide leading producer of the fuel oils from the oil shale. We evaluated the ecotoxicity of water accommodated fraction (WAF) of two Estonian shale fuel oils ("VKG D" and "VKG sweet") to aquatic species belonging to different trophic levels (marine bacteria, freshwater crustaceans and aquatic plants). Artificial fresh water and natural lake water were used to prepare WAFs. "VKG sweet" (lower density) proved more toxic to aquatic species than "VKG D" (higher density). Our data indicate that though shale oils were very toxic to crustaceans, the short-term exposure of Daphnia magna to sub-lethal concentrations of shale fuel oils WAFs may increase the reproductive potential of survived organisms. The weak correlation between measured chemical parameters (C10-C40 hydrocarbons and sum of 16 PAHs) and WAF's toxicity to studied species indicates that such integrated chemical parameters are not very informative for prediction of shale fuel oils ecotoxicity.
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Affiliation(s)
- Irina Blinova
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618, Tallinn, Estonia.
| | - Liina Kanarbik
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618, Tallinn, Estonia
- Department of Chemical and Materials Technology, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia
| | - Mariliis Sihtmäe
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618, Tallinn, Estonia
| | - Anne Kahru
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618, Tallinn, Estonia
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Santander-Avanceña SS, Sadaba RB, Taberna HS, Tayo GT, Koyama J. Acute Toxicity of Water-Accommodated Fraction and Chemically Enhanced WAF of Bunker C Oil and Dispersant to a Microalga Tetraselmis tetrathele. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 96:31-35. [PMID: 26585645 DOI: 10.1007/s00128-015-1696-0] [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: 03/17/2015] [Accepted: 11/11/2015] [Indexed: 06/05/2023]
Abstract
This study assessed the toxicity of water-accommodated fraction (WAF) and chemically enhanced WAF (CEWAF) of bunker C oil and dispersant (DISP) to a microalga, Tetraselmis tetrathele. The 72-h median effective concentration (72-h EC50) of CEWAF and DISP were determined at 3.30% and 2.40%, respectively. The no observed effect concentration (NOEC) of CEWAF to T. tetrathele was at 2.0% and lowest observed effect concentration (LOEC) was at 3.0% while NOEC and LOEC of DISP to T. tetrathele were determined at 1.0% and 2.0%, respectively. The addition of dispersant to oil increased the amount of total PAH present in the CEWAF test solutions. DISP alone was highly toxic, and the toxicity of CEWAF was primarily caused by the presence of dispersant.
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Affiliation(s)
- Sheryll S Santander-Avanceña
- College of Arts and Sciences and Oil Spill Response Program, University of the Philippines Visayas, Miagao, Iloilo, Philippines.
- Aquaculture Department/Southeast Asian Fisheries Development Center, Tigbauan, Iloilo, Philippines.
| | - Resurreccion B Sadaba
- College of Arts and Sciences and Oil Spill Response Program, University of the Philippines Visayas, Miagao, Iloilo, Philippines
| | - Hilario S Taberna
- College of Arts and Sciences and Oil Spill Response Program, University of the Philippines Visayas, Miagao, Iloilo, Philippines
- Iloilo Science and Technology University, Lapaz, Iloilo City, Philippines
| | - Gilma T Tayo
- College of Arts and Sciences and Oil Spill Response Program, University of the Philippines Visayas, Miagao, Iloilo, Philippines
| | - Jiro Koyama
- Faculty of Fisheries, Education and Research Center for Marine Resources and Environment, Kagoshima University, Kagoshima, Japan
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12
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Nassar MZ, El-Din NGS, Gharib SM. Phytoplankton variability in relation to some environmental factors in the eastern coast of Suez Gulf, Egypt. ENVIRONMENTAL MONITORING AND ASSESSMENT 2015; 187:648. [PMID: 26407862 PMCID: PMC4611007 DOI: 10.1007/s10661-015-4874-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 09/16/2015] [Indexed: 06/05/2023]
Abstract
Water samples were seasonally collected from 12 stations of the eastern coast of Suez Gulf during autumn of 2012 and winter, spring, and summer of 2013 in order to investigate phytoplankton community structure in relation to some physicochemical parameters. The study area harbored a diversified phytoplankton community (138 species), belonging to 67 genera. Four algal groups were represented and classified as Bacillariophyceae (90 species), Dinophyceae (28 species), Cyanophyceae (16 species), and Chlorophyceae (4 species). The results indicated a relative high occurrence of some species namely.; Pleurotaenium trabecula of green algae; Chaetoceros lorenzianus, Proboscia alata var. gracillima, Pseudosolenia calcar-avis, and Pseudo-nitzschia pungens of diatoms; Trichodesmium erythraeum and Pseudoanabaena limnetica of cyanophytes. Most of other algal species were fairly distributed at the selected stations of the study area. The total abundance of phytoplankton was relatively low (average of 2989 unit/L) in the eastern coast of Suez Gulf, as compared its western coast and the northern part of the Red Sea. The diversity of phytoplankton species was relatively high (2.35-3.82 nats) with an annual average of 3.22 nats in the present study. The results concluded that most of eastern coast of Suez Gulf is still healthy, relatively unpolluted, and oligotrophic area, which is clearly achieved by the low values of dissolved phosphate (0.025-0.3 μM), nitrate (0.18-1.26 μM), and dissolved ammonium (0.81-5.36 μM). Even if the occurrence of potentially harmful algae species was low, the study area should be monitored continuously. The dissolved oxygen ranged between 1.77 and 8.41 mg/L and pH values between 7.6 and 8.41. The multiple regression analysis showed that the dissolved nitrate and pH values were the most effective factors that controlled the seasonal fluctuations of phytoplankton along the eastern coast of Suez Gulf during 2012-2013.
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Affiliation(s)
- Mohamed Z Nassar
- National Institute of Oceanography and Fisheries, B.O.182, Suez, Egypt.
| | | | - Samiha M Gharib
- National Institute of Oceanography and Fisheries, Alexandria, Egypt
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13
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Ramadass K, Megharaj M, Venkateswarlu K, Naidu R. Toxicity and oxidative stress induced by used and unused motor oil on freshwater microalga, Pseudokirchneriella subcapitata. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:8890-8901. [PMID: 25135168 DOI: 10.1007/s11356-014-3403-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Accepted: 07/29/2014] [Indexed: 06/03/2023]
Abstract
Although used motor oil from automobiles is one of the major pollutants through storm water in urban environments leading to contamination of water bodies, very little information is available on its toxicity towards growth of microalgae. Also, to our knowledge, there are no data on the used motor oil-induced oxidative stress in microalgae. We therefore investigated the toxicity of used and fresh motor oil on growth and antioxidant enzymes of a microalga, Pseudokirchneriella subcapitata. In general, used oil was more toxic to the alga than fresh oil. Used oil at 0.20 % inhibited algal growth, measured in terms of chlorophyll a, by 44 % while fresh oil was nontoxic up to 2.8 %. Water-accommodated fraction (WAF) of the used oil at >50 % concentration exhibited significant toxicity while WAF from fresh oil was nontoxic even up to 100 %. Used oil and its WAF, even at lower concentrations, increased the levels of antioxidant enzymes indicating algal response to the toxicity stress. When the alga was exposed to WAF from fresh motor oil, no alterations in the antioxidant enzyme levels were evident. The present investigation suggests that contamination of aquatic systems with used oil could potentially affect the ecosystem health via disruption of primary producers that are located at the base of the food chain.
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Affiliation(s)
- Kavitha Ramadass
- Centre for Environmental Risk Assessment and Remediation (CERAR), University of South Australia, Mawson Lakes, SA, 5095, Australia
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14
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Chu TV, Torréton JP, Mari X, Nguyen HMT, Pham KT, Pham TT, Bouvier T, Bettarel Y, Pringault O, Bouvier C, Rochelle-Newall E. Nutrient ratios and the complex structure of phytoplankton communities in a highly turbid estuary of Southeast Asia. ENVIRONMENTAL MONITORING AND ASSESSMENT 2014; 186:8555-8572. [PMID: 25200992 DOI: 10.1007/s10661-014-4024-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 08/21/2014] [Indexed: 06/03/2023]
Abstract
Phytoplankton diversity and abundance in estuarine systems are controlled by many factors. Salinity, turbidity, and inorganic nutrient concentrations and their respective ratios have all been proposed as principal factors that structure phytoplankton diversity and influence the emergence of potentially toxic species. Although much work has been conducted on temperate estuaries, less is known about how phytoplankton diversity is controlled in tropical, monsoonal systems that are subject to large, seasonal shifts in hydrology and to rapidly changing land use. Here, we present the results of an investigation into the factors controlling phytoplankton species composition and distribution in a tropical, monsoonal estuary (Bach Dang estuary, North Vietnam). A total of 245 taxa, 89 genera from six algal divisions were observed. Bacillariophyceae were the most diverse group contributing to 51.4 % of the microalgal assemblage, followed by Dinophyceae (29.8 %), Chlorophyceae (10.2 %), Cyanophyceae (3.7 %), Euglenophyceae (3.7 %) and Dictyochophyceae (1.2 %). The phytoplankton community was structured by inorganic nutrient ratios (DSi:DIP and DIN:DIP) as well as by salinity and turbidity. Evidence of a decrease in phytoplankton diversity concomitant with an increase in abundance and dominance of certain species (e.g., Skeletonema costatum) and the appearance of some potentially toxic species over the last two decades was also found. These changes in phytoplankton diversity are probably due to a combination of land use change resulting in changes in nutrient ratios and concentrations and global change as both rainfall and temperature have increased over the last two decades. It is therefore probable in the future that phytoplankton diversity will continue to change, potentially favoring the emergence of toxic species in this system.
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Affiliation(s)
- Thuoc Van Chu
- Institute of Marine Environment and Resources (IMER), Vietnam Academy of Science and Technology (VAST), Haiphong, Viet Nam
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15
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Lewis M, Pryor R. Toxicities of oils, dispersants and dispersed oils to algae and aquatic plants: review and database value to resource sustainability. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2013; 180:345-367. [PMID: 23770072 DOI: 10.1016/j.envpol.2013.05.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 04/23/2013] [Accepted: 05/01/2013] [Indexed: 06/02/2023]
Abstract
Phytotoxicity results are reviewed for oils, dispersants and dispersed oils. The phytotoxicity database consists largely of results from a patchwork of reactive research conducted after oil spills to marine waters. Toxicity information is available for at least 41 crude oils and 56 dispersants. As many as 107 response parameters have been monitored for 85 species of unicellular and multicellular algae, 28 wetland plants, 13 mangroves and 9 seagrasses. Effect concentrations have varied by as much as six orders of magnitude due to experimental diversity. This diversity restricts phytotoxicity predictions and identification of sensitive species, life stages and response parameters. As a result, evidence-based risk assessments for most aquatic plants and petrochemicals and dispersants are not supported by the current toxicity database. A proactive and experimentally-consistent approach is recommended to provide threshold toxic effect concentrations for sensitive life stages of aquatic plants inhabiting diverse ecosystems.
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Affiliation(s)
- Michael Lewis
- U.S. Environmental Protection Agency, Office of Research and Development, 1 Sabine Island Drive, Gulf Breeze, FL 32561, USA.
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Huang YJ, Jiang ZB, Zeng JN, Chen QZ, Zhao YQ, Liao YB, Shou L, Xu XQ. The chronic effects of oil pollution on marine phytoplankton in a subtropical bay, China. ENVIRONMENTAL MONITORING AND ASSESSMENT 2011; 176:517-530. [PMID: 20640504 DOI: 10.1007/s10661-010-1601-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 06/27/2010] [Indexed: 05/29/2023]
Abstract
To evaluate the effects of crude oil water accommodated fraction (WAF) on marine phytoplankton community, natural phytoplankton collected seasonally from the Yueqing bay were exposed to eight groups of crude oil WAF for 15 days under laboratory conditions. Chlorophyll a and cell density were measured, and species of phytoplankton were identified every 24 h to reflect the change of phytoplankton community. The results showed that (1) High concentrations (≥ 2.28 mg l(-1)) of oil pollution would greatly restrain phytoplankton growth (p<0.001), decrease chlorophyll a content and cell density, whereas low concentrations (≤ 1.21 mg l(-1)) did not restrain its growth but rather promoted the phytoplankton growth. (2) The biodiversity, evenness, and species number of phytoplankton were all significantly influenced by crude oil WAF in all seasons (p<0.001). (3) The dominant species changes were different under different pollutant concentrations in different seasons. Different species had different tolerances to the oil pollution, thus leading to abnormal succession.
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Affiliation(s)
- Yi-Jun Huang
- Key Laboratory of Marine Ecosystem and Biogeochemistry, Second Institute of Oceanography, State Oceanic Administration, No. 36 Northern Baochu Road, Hangzhou, 310012, People's Republic of China.
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17
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Nogales B, Lanfranconi MP, Piña-Villalonga JM, Bosch R. Anthropogenic perturbations in marine microbial communities. FEMS Microbiol Rev 2011; 35:275-98. [DOI: 10.1111/j.1574-6976.2010.00248.x] [Citation(s) in RCA: 229] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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18
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Effects of crude oil on marine microbial communities in short term outdoor microcosms. J Microbiol 2010; 48:594-600. [DOI: 10.1007/s12275-010-0199-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Accepted: 07/26/2010] [Indexed: 11/27/2022]
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19
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Jiang Z, Huang Y, Xu X, Liao Y, Shou L, Liu J, Chen Q, Zeng J. Advance in the toxic effects of petroleum water accommodated fraction on marine plankton. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.chnaes.2009.12.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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20
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Petersen DG, Reichenberg F, Dahllöf I. Phototoxicity of pyrene affects benthic algae and bacteria from the Arctic. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:1371-1376. [PMID: 18351119 DOI: 10.1021/es071854n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Phototoxicity of polycyclic aromatic hydrocarbons (PAHs) in the Arctic is important to study since the future PAH load is likely to increase. In combination with the increased UV-light penetration due to ozone layer thinning, phototoxicity may be a potential problem for arctic areas. The aim of this study was to evaluate effects of pyrene and phototoxicity of pyrene on natural algae and bacteria from arctic sediments. Sediments from a shallow-water marine baywere spiked with different pyrene concentrations. Microcosms containing the sediment were incubated under three light regimes, natural sunlight with UV-light, natural sunlight without UV-light, and dark. Significant effects were evident at low pyrene concentrations, particularly in presence of UV-light, indicating phototoxicity. The microalgae were especially sensitive to the phototoxicity of pyrene. Already atthe lowest pyrene concentration (Cfree: 4 nM) algal 14C-incorporation and chlorophyll a content were reduced. The toxic effects of pyrene on the microalgae probably led to the release of organic matter. In agreement with this, bacterial activity increased at high pyrene concentrations indicated by increased oxygen consumption and increased release of inorganic N and P from the sediment. This study indicates that phototoxicity of PAHs may be relevant for sediment communities from shallow marine arctic areas at environmentally relevant pyrene concentrations.
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Affiliation(s)
- Dorthe G Petersen
- National Environmental Research Institute, Department of Marine Ecology, University of Aarhus, Frederiksborgvej 399, 4000 Roskilde, Denmark.
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Teira E, Lekunberri I, Gasol JM, Nieto-Cid M, Alvarez-Salgado XA, Figueiras FG. Dynamics of the hydrocarbon-degrading Cycloclasticus bacteria during mesocosm-simulated oil spills. Environ Microbiol 2007; 9:2551-62. [PMID: 17803779 DOI: 10.1111/j.1462-2920.2007.01373.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We used catalysed reported deposition - fluorescence in situ hybridization (CARD-FISH) to analyse changes in the abundance of the bacterial groups Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes, and of hydrocarbon-degrading Cycloclasticus bacteria in mesocosms that had received polycyclic aromatic hydrocarbons (PAHs) additions. The effects of PAHs were assessed under four contrasting hydrographic conditions in the coastal upwelling system of the Rías Baixas: winter mixing, spring bloom, summer stratification and autumn upwelling. We used realistic additions of water soluble PAHs (approximately 20-30 microg l(-1) equivalent of chrysene), but during the winter period we also investigated the effect of higher PAHs concentrations (10-80 microg l(-1) chrysene) on the bacterial community using microcosms. The most significant change observed was a significant reduction (68 +/- 5%) in the relative abundance of Alphaproteobacteria. The magnitude of the response of Cycloclasticus bacteria (positive with probe CYPU829) to PAHs additions varied depending on the initial environmental conditions, and on the initial concentration of added PAHs. Our results clearly show that bacteria of the Cycloclasticus group play a major role in low molecular weight PAHs biodegradation in this planktonic ecosystem. Their response was stronger in colder waters, when their background abundance was also higher. During the warm periods, the response of Cycloclasticus was limited, possibly due to both, a lower bioavailability of PAHs caused by abiotic factors (solar radiation, temperature), and by inorganic nutrient limitation of bacterial growth.
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Affiliation(s)
- Eva Teira
- Departamento de Ecoloxía e Bioloxía Animal, Universidade de Vigo, Vigo, Spain.
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Nayar S, Miller DJ, Hunt A, Goh BPL, Chou LM. Environmental effects of dredging on sediment nutrients, carbon and granulometry in a tropical estuary. ENVIRONMENTAL MONITORING AND ASSESSMENT 2007; 127:1-13. [PMID: 16897509 DOI: 10.1007/s10661-006-9253-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2005] [Accepted: 04/11/2006] [Indexed: 05/11/2023]
Abstract
This monitoring study encompassed a period prior to dredging, during dredging and post dredging between July 1999 to June 2000 in Ponggol estuary located along the northeastern coast of Singapore. Mean concentrations of sediment nutrients in mg x Kg(-1) (+/- standard error of means) prior to dredging, during dredging and post dredging were 9.75 +/- 4.24, 8.18 +/- 4.29 and 11.46 +/- 4.74 for ammonium, 0.08 +/- 0.05, 0.06 +/- 0.02 and 0.09 +/- 0.01 for nitrite, 0.04 +/- 0.04, 0.11 +/- 0.17 and 0.25 +/- 0.30 for nitrate, 4.83 +/- 3.48, 0.77 +/- 0.48 and 8.33 +/- 9.73 for phosphate respectively. Pre dredge, dredge and post dredge levels of total carbon (TC) were 18.5 +/- 3.7, 20.2 +/- 3.5 and 34.6 +/- 12.0, of total organic carbon (TOC) were 10.5 +/- 2.9, 19.5 +/- 3.6 and 34.6 +/- 12.0 and of total inorganic carbon (TIC) were 7.9 +/- 1.0, 0.7 +/- 0.4 and non detectable in the sediments, respectively. Both, sediment nutrients and carbon registered lower concentrations with onset of dredging, with the exception of nitrate and TOC. A shift in sedimentary carbon from inorganic carbon to organic carbon was also observed with the onset of the dredging activities when the organically enriched historically contaminated layer was exposed. Sediment granulometry showed that the sediments in the estuary were predominantly silt and clay prior to dredging, which changed to sand with onset of dredging. Silt load in the sediments was highest post-dredge. Sediment nutrients and sediment organic carbon were observed to associate with the finer fractions (silt and clay) of sediments. Finer fractions of sediments get resuspended during a dredging event and are dispersed spatially as the result of tides and water movements. Prior to this study, the potential for nutrient release and sediment granulometry due to dredging have been suggested, but there have been few studies of it, especially in the tropics. The baseline information gathered from this study could be used to work out effective management strategies to protect similar tropical ecosystems elsewhere, should there be no other alternative to dredging.
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Affiliation(s)
- S Nayar
- South Australian Research and Development Institute - Aquatic Sciences, 2 Hamra Avenue, West Beach, SA 5024, Australia.
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