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Xie L, Yang B, Xu J, Dan SF, Ning Z, Zhou J, Kang Z, Lu D, Huang H. Effects of intensive oyster farming on nitrogen speciation in surface sediments from a typical subtropical mariculture bay. Sci Total Environ 2024; 916:170092. [PMID: 38246374 DOI: 10.1016/j.scitotenv.2024.170092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 01/06/2024] [Accepted: 01/09/2024] [Indexed: 01/23/2024]
Abstract
The spatial-temporal distributions of various nitrogen (N) species in surface sediments were examined in a typical subtropical mariculture bay (Maowei Sea) in the northern Beibu Gulf to assess the impact of intensive oyster culture activities on sedimentary N speciation. The results indicated that the mean contents of total nitrogen (TN), extractable (labile) nitrogen (LN) and residual nitrogen (RN) in the surface sediments were 33.3 ± 15.5 μmol g-1, 13.8 ± 1.3 μmol g-1 and 19.5 ± 15.0 μmol g-1, respectively, which lacked significant seasonal variability (P > 0.05). Four forms of LN, namely ion extractable form (IEF-N), weak acid extractable form (WAEF-N), strong alkali extractable form (SAEF-N) and strong oxidant extractable form (SOEF-N) were identified based on sequential extraction. SOEF-N was the dominant form of LN, accounting for 67.8 ± 2.5 % and 63.7 ± 5.9 % in summer and winter, respectively. Spatially, the contents of sedimentary TN, LN, RN, WAEF-N and SOEF-N in intensive mariculture areas (IMA) were significantly higher than those in non-intensive mariculture areas (NIMA) during summer (P < 0.05). Stable nitrogen isotope (δ15N) mixing model revealed that shellfish biodeposition was the predominant source of sedimentary TN in IMA with a contribution of 67.8 ± 23.0 %, approximately 5.4 times that of NIMA (12.6 ± 3.3 %). Significant positive correlations (P < 0.05) were observed between most forms of N species (WAEF-N, SOEF-N, LN and RN) and shellfish-biodeposited N in the surface sediments during summer, indicating that intensive oyster farming greatly enhanced sedimentary TN accumulation.
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Affiliation(s)
- Lei Xie
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China
| | - Bin Yang
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Guangxi Key Laboratory of Marine Environment Change and Disaster in Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China.
| | - Jie Xu
- Center for Regional Ocean, Department of Ocean Science and Technology, Faculty of Science and Technology, University of Macau, Taipa, Macau
| | - Solomon Felix Dan
- Guangxi Key Laboratory of Marine Environment Change and Disaster in Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Zhiming Ning
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning 530004, China
| | - Jiaodi Zhou
- Guangxi Key Laboratory of Marine Environment Change and Disaster in Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China; Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning 530004, China
| | - Zhenjun Kang
- Guangxi Key Laboratory of Marine Environment Change and Disaster in Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Dongliang Lu
- Guangxi Key Laboratory of Marine Environment Change and Disaster in Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
| | - Haifang Huang
- Guangxi Key Laboratory of Marine Environment Change and Disaster in Beibu Gulf, Beibu Gulf University, Qinzhou 535011, China
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McMenemy P, Kleczkowski A, Taylor NGH. Modelling norovirus dynamics within oysters emphasises potential food safety issues associated with current testing & depuration protocols. Food Microbiol 2023; 116:104363. [PMID: 37689418 DOI: 10.1016/j.fm.2023.104363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/02/2023] [Accepted: 08/08/2023] [Indexed: 09/11/2023]
Abstract
Norovirus is a significant global cause of viral gastroenteritis, with raw oyster consumption often linked to such outbreaks due to their filter-feeding in harvest waters. National water quality and depuration/relaying times are often classified using Escherichia coli, a poor proxy for norovirus levels in shellfish. The current norovirus assay is limited to only the digestive tracts of oysters, meaning the total norovirus load of an oyster may differ from reported results. These limitations motivated this work, building upon previous modelling by the authors, and considers the sequestration of norovirus into observed and cryptic (unobservable) compartments within each oyster. Results show that total norovirus levels in shellfish batches exhibit distinct peaks during the early depuration stages, with each peak's magnitude dependent on the proportion of cryptic norovirus. These results are supported by depuration trial data and other studies, where viral levels often exhibit multiphase decays. This work's significant result is that any future norovirus legislation needs to consider not only the harvest site's water classification but also the total viral load present in oysters entering the market. We show that 62 h of depuration should be undertaken before any norovirus testing is conducted on oyster samples, being the time required for cryptic viral loads to have transited into the digestive tracts where they can be detected by current assay, or have exited the oyster.
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Affiliation(s)
- Paul McMenemy
- University of Strathclyde, 16 Richmond Street, Glasgow, G1 1XQ, United Kingdom; University of Stirling, Airthrey Road, Stirling, FK9 4LA, United Kingdom.
| | - Adam Kleczkowski
- University of Strathclyde, 16 Richmond Street, Glasgow, G1 1XQ, United Kingdom; University of Stirling, Airthrey Road, Stirling, FK9 4LA, United Kingdom.
| | - Nick G H Taylor
- Cefas, The Nothe, Barrack Road, Weymouth, DT4 8UB, United Kingdom; Office for National Statistics, 2 Marsham Street, London, SW1P 4DF, United Kingdom
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Hingant M, Mallarino S, Conforto E, Dubillot E, Barbier P, Bringer A, Thomas H. Artificial weathering of plastics used in oyster farming. Sci Total Environ 2023; 868:161638. [PMID: 36649774 DOI: 10.1016/j.scitotenv.2023.161638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/03/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
With the omnipresence of plastic litter from oyster farming in marine coastal areas, the objective of this work was to better understand the weathering of plastics used in this field, focusing on oyster spat collectors. During their use, around fifteen years, collectors made of polypropylene (PP) undergo numerous degradations, alternatively submerged, emerged in seawater, and stored outdoor until the next cycle. They weaken, crack, break, end up fragmenting and disseminated in the environment as microplastics associated to persistent organic pollutants. In this work, a comparison of 55 months of in situ weathering with five months of artificial weathering in air or in artificial seawater in a homemade UV chamber was conducted to better understand the mechanisms involved. Chemical, thermal and surface characterizations of virgin and weathered samples were conducted using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Environmental Scanning Electron Microscopy (ESEM). After 55 months of in situ weathering, collectors were notably damaged with large fissures and loss of microplastics (MPs) associated with an increase of carbonyl index values and a decrease of melting temperatures and crystallinity rates. Considering only UV irradiation, five months of artificial weathering at 30 °C under continuous irradiation of 6.9 W/m2 under UV lamps (295-400 nm) reproduced approximately 4.4 months of natural sunlight. Artificial weathering confirmed that photooxidation by combined effects of UV rays and oxygen was the main weathering mechanism and was reduced in seawater. These results help to understand the mechanisms involved in the weathering of these collectors in the marine environment and provide valuable information for industrials and professionals. Our study suggests a better storage away from UV rays and a reduction of the duration of use compared to current practices.
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Affiliation(s)
- Marion Hingant
- Littoral Environnement et Sociétés (LIENSs), UMRi 7266 CNRS - La Rochelle Université, 2 rue Olympe de Gouges, F-17042 La Rochelle Cedex 01, France.
| | - Stéphanie Mallarino
- Laboratoire des Sciences de l'Ingénieur pour l'Environnemen (LaSIE), UMR 7356 CNRS - La Rochelle Université, Avenue Michel Crépeau, 17042 La Rochelle, France
| | - Egle Conforto
- Laboratoire des Sciences de l'Ingénieur pour l'Environnemen (LaSIE), UMR 7356 CNRS - La Rochelle Université, Avenue Michel Crépeau, 17042 La Rochelle, France
| | - Emmanuel Dubillot
- Littoral Environnement et Sociétés (LIENSs), UMRi 7266 CNRS - La Rochelle Université, 2 rue Olympe de Gouges, F-17042 La Rochelle Cedex 01, France
| | - Pierrick Barbier
- Centre pour l'Aquaculture, la Pêche et l'Environnement de Nouvelle-Aquitaine (CAPENA), Prise de Terdoux, 17480 Le Château d'Oléron, France
| | - Arno Bringer
- Littoral Environnement et Sociétés (LIENSs), UMRi 7266 CNRS - La Rochelle Université, 2 rue Olympe de Gouges, F-17042 La Rochelle Cedex 01, France; Qualyse, 5 Allée de l'Océan, 17000 La Rochelle, France
| | - Hélène Thomas
- Littoral Environnement et Sociétés (LIENSs), UMRi 7266 CNRS - La Rochelle Université, 2 rue Olympe de Gouges, F-17042 La Rochelle Cedex 01, France
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Oyanedel D, Rojas R, Brokordt K, Schmitt P. Crassostrea gigas oysters from a non-intensive farming area naturally harbor potentially pathogenic vibrio strains. J Invertebr Pathol 2023; 196:107856. [PMID: 36414122 DOI: 10.1016/j.jip.2022.107856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 09/05/2022] [Accepted: 11/15/2022] [Indexed: 11/21/2022]
Abstract
Farming intensification and climate change are inevitably linked to pathogen emergence in aquaculture. In this context, infectious diseases associated with vibrios span all developmental stages of the Pacific Oyster Crassostrea gigas. Moreover, virulence factors associated with pathogenicity spread among the vibrio community through horizontal gene transfer as part of the natural eco-evolutive dynamic of this group. Therefore, risk factors associated with the emergence of pathogens should be assessed before the appearance of mass mortalities in developing rearing areas. In this context, we characterized the vibrios community associated with oysters cultured in a non-intensive area free of massive mortalities located at Tongoy bay, Chile, through a culture-dependent approach. We taxonomically affiliated our isolates at the species level through the partial sequencing of the heat shock protein 60 gene and estimated their virulence potential through experimental infection of juvenile C. gigas. The vibrio community belonged almost entirely to the Splendidus clade, with Vibrio lentus being the most abundant species. The virulence potential of selected isolates was highly contrasted with oyster survival ranging between 100 and 30 %. Moreover, different vibrio species affected oyster survival at different rates, for instance V. splendidus TO2_12 produced most mortalities just 24 h after injection, while the V. lentus the most virulent strain TO6_11 produced sustained mortalities reaching 30 % of survival at day 4 after injection. Production of enzymes associated with pathogenicity was detected and hemolytic activity was positive for 50 % of the virulent strains and negative for 90 % of non-virulent strains, representing the phenotype that better relates to the virulence status of strains. Overall, results highlight that virulence is a trait present in the absence of disease expression, and therefore the monitoring of potentially pathogenic groups such as vibrios is essential to anticipate and manage oyster disease emergence in both established and under-development rearing areas.
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Affiliation(s)
- Daniel Oyanedel
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso 2340000, Chile.
| | - Rodrigo Rojas
- Laboratorio de Patobiología Acuática, Departamento de Acuicultura, Universidad Católica del Norte, Larrondo 1281, Coquimbo 1780000, Chile; Centro de Innovación Acuícola (AquaPacífico), Universidad Católica del Norte, Coquimbo 1780000, Chile
| | - Katherina Brokordt
- Laboratorio de Fisiología y Genética Marina (FIGEMA), Departamento de Acuicultura, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo 1780000, Chile; Centro de Estudios avanzados en Zonas Áridas (CEAZA), Coquimbo 1780000, Chile; Centro de Innovación Acuícola (AquaPacífico), Universidad Católica del Norte, Coquimbo 1780000, Chile
| | - Paulina Schmitt
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso 2340000, Chile
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Teng CJ, Su YJ, Yeh CY, Jie WB. Predation of Oysters Using an Autonomic Pharynx in the Oyster Leech Cryptostylochus sp. (Polycladida: Stylochidae). Zool Stud 2022; 60:e7. [PMID: 35774254 PMCID: PMC9168733 DOI: 10.6620/zs.2022.61-07] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 01/28/2022] [Indexed: 06/15/2023]
Abstract
Oyster farming has been threatened by marine flatworms for over 40 years, but few studies have been done to address this issue. Here, we examine the predatory behavior of the polyclad flatworm Cryptostylochus sp. from Penghu, Taiwan. Its predation process consists of three parts: the attack, invasion, and ingestion period. During the attack period, which begins 4 or more hours before the invasion, protruding pharynges form fragments that we call "autonomic pharynges". The autonomic pharynx is translucent white, membrane-like, and variable in length. Using time-lapse photography, we show that the pharynx moves around slowly and independently for roughly 10 hours before losing mobility. The autonomic pharynx moved toward the edge of the oyster shell and increases the frequency at which the oyster or clam opens and closes compared to the control group. The passageway demonstrates negative phototactic behavior in petri dishes. Linear regression showed a positive correlation between the number of autonomic pharynges and the clam mortality rate. Histological dissections showed that clam mantle tissue is externally digested by the autonomic pharynx. The fragments of multi-branched ruffled pharynx from polyclad flatworms slowly detach and play a critical role during the period of the attack on bivalves.
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Affiliation(s)
- Ching-Jung Teng
- National Experimental High School at Hsinchu Science Park, No.300, Jieshou Rd, East Dist., Hsinchu City 300, Taiwan. E-mail: (Jie); (Teng); (Su); (Yeh)
| | - Ying-Jung Su
- National Experimental High School at Hsinchu Science Park, No.300, Jieshou Rd, East Dist., Hsinchu City 300, Taiwan. E-mail: (Jie); (Teng); (Su); (Yeh)
| | - Chih-Yu Yeh
- National Experimental High School at Hsinchu Science Park, No.300, Jieshou Rd, East Dist., Hsinchu City 300, Taiwan. E-mail: (Jie); (Teng); (Su); (Yeh)
| | - Wei-Ban Jie
- National Experimental High School at Hsinchu Science Park, No.300, Jieshou Rd, East Dist., Hsinchu City 300, Taiwan. E-mail: (Jie); (Teng); (Su); (Yeh)
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Yan Q, Song J, Zhou J, Han Y, Cai Z. Biodeposition of oysters in an urbanized bay area alleviates the black-malodorous compounds in sediments by altering microbial sulfur and iron metabolism. Sci Total Environ 2022; 817:152891. [PMID: 34995586 DOI: 10.1016/j.scitotenv.2021.152891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/17/2021] [Accepted: 12/30/2021] [Indexed: 06/14/2023]
Abstract
The occurrence of the 'black-malodorous phenomenon' in a waterbody is a clear sign of a highly eutrophic bay, the formation of which is associated with microbial sulfur and iron metabolism in the sediments. Oyster farming restoration has been widely studied as an important method for treating eutrophication and related ecological problems. However, few studies focus on the ecosystem-level consequences of oyster farming concerning microbial sulfur and iron cycles in the sediment. Here, we compared the physicochemical features and microbial functions of oyster farms with those of reference areas using the Geochip5.0 technique. Our results showed a significant reduction of acid volatile sulfide (AVS) content associated with oyster farming, thus alleviating the black-malodorous status of Shenzhen Bay in China. Oyster farming created loose and porous sedimentary structures and stimulated the oxidation of black-odorous compounds. Moreover, we observed that the introduction of oysters changed microbial biodiversity significantly based on gyrB gene structure, with typical sulfur- and iron-cycling microbes being enriched. We also demonstrated that microbial abilities involved in sulfur and iron metabolism were greatly increased in oyster farming areas compared with reference areas. Under such circumstances, some cascading processes (AVS uptake and rates of organic matter turnover) were improved, which eventually contributed to black odor reduction. From the microecological perspective, we conclude that the biodeposition of oysters was the key factor for water retention and improvement of microbial metabolism. This study suggests that biodeposition shapes the microbial functional communities in adjacent territories and presumably alleviates the black-malodorous compounds in sediments.
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Affiliation(s)
- Qi Yan
- School of Life Science, Tsinghua University, Beijing 100083, PR China
| | - Junting Song
- The Institute for Ocean Engineering, Tsinghua Shenzhen International Graduate School (SIGS), Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Jin Zhou
- The Institute for Ocean Engineering, Tsinghua Shenzhen International Graduate School (SIGS), Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Yilin Han
- The Institute for Ocean Engineering, Tsinghua Shenzhen International Graduate School (SIGS), Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Zhonghua Cai
- The Institute for Ocean Engineering, Tsinghua Shenzhen International Graduate School (SIGS), Tsinghua University, Shenzhen 518055, Guangdong Province, PR China.
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Onduka T, Mizuno KI, Shikata T, Mastubara T, Onitsuka G, Hamaguchi M. Assessment of the risk posed by three antifouling biocides to Pacific oyster embryos and larvae in Hiroshima Bay, Japan. Environ Sci Pollut Res Int 2022; 29:9011-9022. [PMID: 34494197 DOI: 10.1007/s11356-021-16346-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
The Pacific oyster (Crassostrea gigas) is an important species in oyster farming worldwide, including in Japan. Hiroshima Bay is one of the most important oyster farming areas in Japan. We investigated the occurrence of antifouling biocides used worldwide including diuron, Irgarol 1051 (Irgarol), and 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT), which have been detected at sub-ppb levels in seawater in Japan, and estimated their no observed effect concentrations (NOECs). In recent years, the spat settlement of Pacific oysters has become poor, which presents a challenge for oyster aquaculture in Hiroshima Bay; hence, we conducted embryotoxicity and larva settlement tests using Pacific oysters. Compared to diuron and Irgarol, DCOIT exhibited a higher toxicity toward oyster embryos, and the minimum 24-h NOEC toxicity value for the oyster embryos was <3 ng/L. The highest concentrations of diuron, Irgarol, and DCOIT in the environmental seawater in the Seto Inland Sea were 27.6, 3.2, and 24 ng/L, respectively. Considering the NOECs, the environmental concentrations of these biocides suggest that the ecological risks posed by diuron and Irgarol are low, whereas those posed by DCOIT are high. However, the rate of detection of DCOIT was low because it degraded rapidly in the seawater before treatment for chemical analysis, except in the case of the treatment on the research vessel.
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Affiliation(s)
- Toshimitsu Onduka
- Hatsukaichi Branch, Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima, 739-0452, Japan.
| | - Ken-Ichiro Mizuno
- Fisheries and Ocean Technologies Center, Hiroshima Prefectural Technology Research Institute, 6-21-1 Ondochō Hatami, Kure, Hiroshima, 737-1207, Japan
| | - Tomoyuki Shikata
- Hatsukaichi Branch, Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima, 739-0452, Japan
- Goto Field Station, Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 122-7 Tamanouramachi-Nunoura, Goto, Nagasaki, 853-0508, Japan
| | - Tadashi Mastubara
- Hatsukaichi Branch, Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima, 739-0452, Japan
| | - Goh Onitsuka
- Hatsukaichi Branch, Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima, 739-0452, Japan
| | - Masami Hamaguchi
- Hatsukaichi Branch, Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima, 739-0452, Japan
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Vanhuysse C, Normand J, Lepoittevin M, Orvain F. Changes in benthic macrofauna in oyster parks during an OsHV-1 μVar oyster spat mortality outbreak. Mar Pollut Bull 2021; 166:112239. [PMID: 33744802 DOI: 10.1016/j.marpolbul.2021.112239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
In intertidal areas, oyster farming creates a crosshatching pattern between oyster tables and aisles. Tables provide a refuge from the current and solar irradiance and the oysters facilitate the accumulation of OM, thereby structuring the spatial organization of the associated macrozoobenthic community at mesoscale. The aim of this study was to describe the quality of the oyster table environment at small scale and the response of the macrozoobenthic community to OsHV-1 μvar oyster mortality. The species assemblage was dominated by Golfingia vulgaris, Tubificoides benedii, Capitella capitata and Scoloplos armiger. The table habitat appeared to be in a bad ecological state throughout the 2-month survey (May and June 2017), whereas in the aisle, eutrophication occurred lately and was clearly related to be due to the massive stranding of dead seaweed at the end of the survey (in early July). So, this disturbance of the species assemblage seemed to occur in two phases: 1) after oyster spat mortality and 2) after seaweed stranding resulted in a bad ecological status, as revealed by macrofaunal indicators. Large quantities of OsHV-1 DNA were also found in some species, including small crabs and amphipods, one week after the mortality crisis, but there is no apparent virus reservoir found in the benthic species.
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Affiliation(s)
- Charles Vanhuysse
- BOREA - Biologie des ORganismes et Ecosystèmes Aquatiques MNHN, UPMC, UCN, CNRS-8207, IRD-207 UFR Sciences, Université de Caen Normandie, Esplanade de la Paix - CS, 14032 CAEN Cedex 5, France.
| | - Julien Normand
- Ifremer, Laboratoire Environnement Ressources de Normandie, Avenue du Général de Gaulle, 14 520 Port en Bessin, France
| | - Mélanie Lepoittevin
- BOREA - Biologie des ORganismes et Ecosystèmes Aquatiques MNHN, UPMC, UCN, CNRS-8207, IRD-207 UFR Sciences, Université de Caen Normandie, Esplanade de la Paix - CS, 14032 CAEN Cedex 5, France
| | - Francis Orvain
- BOREA - Biologie des ORganismes et Ecosystèmes Aquatiques MNHN, UPMC, UCN, CNRS-8207, IRD-207 UFR Sciences, Université de Caen Normandie, Esplanade de la Paix - CS, 14032 CAEN Cedex 5, France.
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Jiang Z, Du P, Liao Y, Liu Q, Chen Q, Shou L, Zeng J, Chen J. Oyster farming control on phytoplankton bloom promoted by thermal discharge from a power plant in a eutrophic, semi-enclosed bay. Water Res 2019; 159:1-9. [PMID: 31075499 DOI: 10.1016/j.watres.2019.04.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 04/01/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
Temperature increase caused by thermal discharge from power plants promotes phytoplankton growth and frequent bloom in eutrophic subtropical waters, particularly in cold seasons. Suspension filter-feeding bivalves show size-selective grazing on phytoplankton. Thus, we hypothesized that algal bloom under thermal stimulation could be controlled and that phytoplankton community was structured by oyster farming. Here, ten cruises were conducted in two oyster farms (OFs) and control areas (CAs) adjacent to the Ninghai Power Plant in the upper section of Xiangshan Bay during 2009-2015. We found that thermal discharge induced severe winter algal blooms. Phytoplankton abundance and chlorophyll a (chla) were significantly lower (46.3% and 28.3%, respectively) in OF than in CA, indicating a high filtration efficiency by oysters and the associated biofouling assemblages. In addition, oyster farming significantly increased species richness (by 26.3%), Shannon-Wiener diversity (by 38.3%), and Pielou's evenness indices (by 28.8%) and reduced suspended solids (by 12.2%), total organic carbon (by 18.4%), dissolved inorganic nitrogen (by 1.5%), and phosphorus (by 3.7%). Furthermore, oyster farming considerably reduced (increased) micro-chla contribution (pheophytin/chla) by 34.8% (71.1%), suggesting a strong size-selective grazing on phytoplankton. Analysis of similarity revealed a significant difference in phytoplankton community composition between OF and CA. However, after the removal of culture rafts, all the abundance, chla, species diversity, dominant species, size structure, and community composition of phytoplankton showed no significant difference. Our study demonstrated that oyster farming effectively alleviated eutrophication and algal bloom and enhanced phytoplankton diversity, which provides guidance for aquaculture and ecological restoration in subtropical coastal eutrophic waters.
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Affiliation(s)
- Zhibing Jiang
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China; Function Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Ping Du
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China; Function Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China
| | - Yibo Liao
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China; State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Qiang Liu
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Quanzhen Chen
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Lu Shou
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China.
| | - Jiangning Zeng
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China.
| | - Jianfang Chen
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China; State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
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