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Ma Q, Zhang R, Wei Y, Liang M, Xu H. Effects of Intermittent and Chronic Hypoxia on Fish Size and Nutrient Metabolism in Tiger Puffer ( Takifugu rubripes). Animals (Basel) 2024; 14:2470. [PMID: 39272255 PMCID: PMC11393956 DOI: 10.3390/ani14172470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2024] [Revised: 08/21/2024] [Accepted: 08/23/2024] [Indexed: 09/15/2024] Open
Abstract
Intermittent and chronic hypoxia are common stresses to marine fish, but the different responses of fish to intermittent and chronic hypoxia have not been well-known. In this study, tiger puffers were farmed in normoxia conditions (NO, 6.5 ± 0.5 mg/L), intermittent hypoxia (IH, 6.5 ± 0.5 mg/L in the day and 3.5 ± 0.5 mg/L in the night), or choric hypoxia (CH, 3.5 ± 0.5 mg/L) conditions for 4 weeks, after which the growth, nutrient metabolism and three hifα isoforms expression were measured. Both intermittent and chronic hypoxia decreased the fish growth and visceral weight but increased the feed conversion ratio and blood hemoglobin content. Chronic hypoxia but not intermittent hypoxia promoted protein synthesis and whole-fish protein content by activating mtor gene expression and promoted the glycolysis pathway by activating gene expression of hif1α and hif2α. Intermittent hypoxia but not chronic hypoxia decreased the hepatic lipid synthesis by inhibiting fasn and srebf1 gene expression. Meanwhile, intermittent hypoxia reduced the monounsaturated fatty acid content but increased the n-3 polyunsaturated fatty acids percentage. The results of this study clarified the adaptive mechanism of tiger puffer to intermittent and chronic hypoxia, which provides important information about mechanisms of hypoxia adaption in fish.
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Affiliation(s)
- Qiang Ma
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
| | - Renxiao Zhang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
- Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Yuliang Wei
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Mengqing Liang
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Houguo Xu
- State Key Laboratory of Mariculture Biobreeding and Sustainable Goods, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao Marine Science and Technology Center, Qingdao 266237, China
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2
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Moore WS, Benitez-Nelson C, Schutte C, Moody A, Shiller A, Sibert RJ, Joye S. SGD-OD: investigating the potential oxygen demand of submarine groundwater discharge in coastal systems. Sci Rep 2024; 14:9249. [PMID: 38649393 PMCID: PMC11035578 DOI: 10.1038/s41598-024-59229-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 04/08/2024] [Indexed: 04/25/2024] Open
Abstract
Submarine groundwater discharge (SGD) supplies nutrients, carbon, metals, and radionuclide tracers to estuarine and coastal waters. One aspect of SGD that is poorly recognized is its direct effect on dissolved oxygen (DO) demand in receiving waters, denoted here as SGD-OD. Sulfate-mediated oxidation of organic matter in salty coastal aquifers produces numerous reduced byproducts including sulfide, ammonia, dissolved organic carbon and nitrogen, methane, and reduced metals. When these byproducts are introduced to estuarine and coastal systems by SGD and are oxidized, they may substantially reduce the DO concentration in receiving waters and impact organisms living there. We consider six estuarine and coastal sites where SGD derived fluxes of reduced byproducts are well documented. Using data from these sites we present a semiquantitative model to estimate the effect of these byproducts on DO in the receiving waters. Without continued aeration with atmospheric oxygen, the study sites would have experienced periodic hypoxic conditions due to SGD-OD. The presence of H2S supplied by SGD could also impact organisms. This process is likely prevalent in other systems worldwide.
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Affiliation(s)
- Willard S Moore
- School of the Earth, Ocean, & Environment, University of South Carolina, Columbia, SC, USA.
| | - Claudia Benitez-Nelson
- School of the Earth, Ocean, & Environment, University of South Carolina, Columbia, SC, USA
| | - Charles Schutte
- Department of Environmental Science, Rowan University, Glassboro, NJ, USA
| | - Amy Moody
- Division of Marine Science, Stennis Space Center, University of Southern Mississippi, Hattiesburg, MS, USA
| | - Alan Shiller
- Division of Marine Science, Stennis Space Center, University of Southern Mississippi, Hattiesburg, MS, USA
| | - Ryan J Sibert
- Department of Marine Sciences, University of Georgia, Athens, GA, USA
| | - Samantha Joye
- Department of Marine Sciences, University of Georgia, Athens, GA, USA
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3
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Luczkovich JJ, Sprague MW, Paerl HW. Bottom water hypoxia suppresses fish chorusing in estuariesa). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2024; 155:2014-2024. [PMID: 38470188 DOI: 10.1121/10.0025289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 02/27/2024] [Indexed: 03/13/2024]
Abstract
Hypoxia in coastal ecosystems is increasing as a result of water quality declines from nutrient pollution. Hypoxia negatively affects fish populations and marine life, limiting their spawning habitats, population size, and growth. In this study, two approaches were used to understand the effect of hypoxia on the chorusing and reproductive behavior of fishes in estuaries. One approach used a water quality meter integrated with a prototype passive acoustic recorder, developed to monitor dissolved oxygen and fish chorusing simultaneously and continuously at sites with normoxic and hypoxic conditions. In a second approach, passive acoustic recorders were deployed near ambient water quality monitoring stations, monitored by the North Carolina agencies in estuaries where hypoxia occurs periodically. In both approaches, when hypoxia (dissolved oxygen < 4.0 mg/L) occurred, fish chorusing was diminished or ceased. A strong correlation was observed between bottom water dissolved oxygen and the power spectral density in a 100-200 Hz frequency band associated with red drum (Sciaenops ocellatus, Sciaenidae) calling. Passive acoustic monitoring stations and integrated passive acoustic and water quality meters should be used in estuarine hypoxia monitoring efforts to examine the expanding areas of hypoxia and its impact on fish critical spawning habitats.
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Affiliation(s)
- Joseph J Luczkovich
- Department of Biology, East Carolina University, Greenville, North Carolina 27858, USA
| | - Mark W Sprague
- Department of Physics, East Carolina University, Greenville, North Carolina 27858, USA
| | - Hans W Paerl
- Institute of Marine Sciences, University of North Carolina, Morehead City, North Carolina 28557, USA
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4
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Thambithurai D, Kuparinen A. Environmental forcing alters fisheries selection. Trends Ecol Evol 2024; 39:131-140. [PMID: 37743188 PMCID: PMC10850982 DOI: 10.1016/j.tree.2023.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/21/2023] [Accepted: 08/29/2023] [Indexed: 09/26/2023]
Abstract
Fishing-induced evolution (FIE) threatens the ecology, resilience, and economic value of fish populations. Traits under selection, and mechanisms of selection, can be influenced by abiotic and biotic perturbations, yet this has been overlooked. Here, we present the fishery selection continuum, where selection ranges from rigid fisheries selection to flexible fisheries selection. We provide examples on how FIE may function along this continuum, and identify selective processes that should be considered less or more flexible. We also introduce fishery reaction norms, which serve to conceptualise how selection from fishing may function in a dynamic context. Ultimately, we suggest an integrative approach to studying FIE that considers the environmental conditions in which it functions.
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Affiliation(s)
- Davide Thambithurai
- MARBEC, University of Montpellier, CNRS, Ifremer, IRD, Sète, France; School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, UK.
| | - Anna Kuparinen
- Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland.
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5
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Liu T, Lu Y, Sun M, Shen H, Niu D. Effects of acute hypoxia and reoxygenation on histological structure, antioxidant response, and apoptosis in razor clam Sinonovacula constricta. FISH & SHELLFISH IMMUNOLOGY 2024; 145:109310. [PMID: 38142828 DOI: 10.1016/j.fsi.2023.109310] [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: 10/19/2023] [Revised: 11/21/2023] [Accepted: 12/14/2023] [Indexed: 12/26/2023]
Abstract
Hypoxia is one of the major environmental problems limiting the healthy development of intensive aquaculture. Marine benthic shellfish are encountering heightened problems related to hypoxic stress as a result of ongoing human activities and aquaculture operations. Razor clam Sinonovacula constricta, a commercially valuable shellfish, has not yet been reported in studies on physiological changes caused by hypoxia and reoxygenation. To understand the negative effects of hypoxia and reoxygenation on the clams, we set up two low-oxygen concentration groups (DO 2.0 mg/L and DO 0.5 mg/L) and assessed multiple aspects of oxidative damage to their hepatopancreas and gills. After the hypoxic stress, the two tissues of the razor clam suffered varying degrees of damage, including cell degeneration and disruption of mitochondrial cristae. After reoxygenation, the 2.0 mg/L group recovered substantially, but the clams in the 0.5 mg/L group still unrecovered. The activities of antioxidant enzymes (MDA, T-AOC, SOD, GPX, and CAT) in clams were considerably altered by acute hypoxia and reoxygenation. Briefly, there was a growing and then declining trend in MDA, T-AOC, and SOD activities in the hepatopancreas, whereas GPX and CAT activities showed the converse trend. In the hepatopancreas and gills, the level of anti-apoptotic gene Bcl-2 transcripts gradually decreased with the duration of hypoxia and increased following reoxygenation. However, changes in the transcript level of the pro-apoptotic gene Bax were in contrast to that of Bcl-2. The TUNEL assay revealed that hypoxia caused apoptosis. Furthermore, at DO 0.5 mg/L, the degree of apoptosis was more significant than at DO 2.0 mg/L, and hepatopancreatic apoptosis was more severe than gill apoptosis. Collectively, our findings imply that hypoxia induces oxidative stress, histological damage, and apoptosis in razor clams in a concentration-dependent and tissue-specific manner. These consequences serve as a reminder that prolonged recovery periods may be required for razor clams to fully recover from oxidative damage resulting from hypoxia-reoxygenation episodes.
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Affiliation(s)
- Tao Liu
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-culture of Aquaculture Animals, Shanghai Ocean University, Shanghai, 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China
| | - Yang Lu
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-culture of Aquaculture Animals, Shanghai Ocean University, Shanghai, 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China
| | - Mengying Sun
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-culture of Aquaculture Animals, Shanghai Ocean University, Shanghai, 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China
| | - Heding Shen
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-culture of Aquaculture Animals, Shanghai Ocean University, Shanghai, 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China.
| | - Donghong Niu
- Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-culture of Aquaculture Animals, Shanghai Ocean University, Shanghai, 201306, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Huaihai Institute of Technology, Lianyungang, 222005, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China.
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6
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Lima ARA, Booms EM, Lopes AR, Martins-Cardoso S, Novais SC, Lemos MFL, Ribeiro L, Castanho S, Candeias-Mendes A, Pousão-Ferreira P, Faria AM. Early life stage mechanisms of an active fish species to cope with ocean warming and hypoxia as interacting stressors. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 341:122989. [PMID: 37984477 DOI: 10.1016/j.envpol.2023.122989] [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: 08/22/2023] [Revised: 11/01/2023] [Accepted: 11/16/2023] [Indexed: 11/22/2023]
Abstract
Ocean's characteristics are rapidly changing, modifying environmental suitability for early life stages of fish. We assessed whether the chronic effects of warming (24 °C) and hypoxia (<2-2.5 mg L-1) will be amplified by the combination of these stressors on mortality, growth, behaviour, metabolism and oxidative stress of early stages of the white seabream Diplodus sargus. Combined warming and hypoxia synergistically increased larval mortality by >51%. Warming induced faster growth in length and slower gains in weight when compared to other treatments. Boldness and exploration were not directly affected, but swimming activity increased under all test treatments. Under the combination of warming and hypoxia, routine metabolic rate (RMR) significantly decreases when compared to other treatments and shows a negative thermal dependence. Superoxide dismutase and catalase activities increased under warming and were maintained similar to control levels under hypoxia or under combined stressors. Under hypoxia, the enzymatic activities were not enough to prevent oxidative damages as lipid peroxidation and DNA damage increased above control levels. Hypoxia reduced electron transport system activity (cellular respiration) and isocitrate dehydrogenase activity (aerobic metabolism) below control levels. However, lactate dehydrogenase activity (anaerobic metabolism) did not differ among treatments. A Redundancy Analysis showed that ∼99% of the variability in mortality, growth, behaviour and RMR among treatments can be explained by molecular responses. Mortality and growth are highly influenced by oxidative stress and energy metabolism, exhibiting a positive relationship with reactive oxygen species and a negative relationship with aerobic metabolism, regardless of treatment. Under hypoxic condition, RMR, boldness and swimming activity have a positive relationship with anaerobic metabolism regardless of temperature. Thus, seabreams may use anaerobic reliance to counterbalance the effects of the stressors on RMR, activity and growth. The outcomes suggests that early life stages of white seabream overcame the single and combined effects of hypoxia and warming.
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Affiliation(s)
- André R A Lima
- MARE-Marine and Environmental Sciences Centre, ARNET-Aquatic Research Infrastructure Network Associate Laboratory, ISPA-Instituto Universitário, Rua Jardim Do Tabaco 34, 1149-041, Lisbon, Portugal.
| | - Emily M Booms
- IMBRSea-The International Master of Science in Marine Biological Resources, Universities Consortium, Ghent University, Krijgslaan, Ghent, Belgium
| | - Ana Rita Lopes
- MARE-Marine and Environmental Sciences Centre, ARNET-Aquatic Research Infrastructure Network Associate Laboratory, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016, Lisbon, Portugal; Department of Animal Biology, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-013, Lisboa, Portugal
| | - Sara Martins-Cardoso
- MARE-Marine and Environmental Sciences Centre, ARNET-Aquatic Research Infrastructure Network Associate Laboratory, ISPA-Instituto Universitário, Rua Jardim Do Tabaco 34, 1149-041, Lisbon, Portugal
| | - Sara C Novais
- MARE - Marine and Environmental Sciences Centre, ARNET-Aquatic Research Infrastructure Network Associate Laboratory, ESTM, Polytechnic of Leiria, Peniche, Portugal
| | - Marco F L Lemos
- MARE - Marine and Environmental Sciences Centre, ARNET-Aquatic Research Infrastructure Network Associate Laboratory, ESTM, Polytechnic of Leiria, Peniche, Portugal
| | - Laura Ribeiro
- Portuguese Institute for the Sea and Atmosphere - IPMA, Aquaculture Research Station - EPPO, Olhão, Portugal
| | - Sara Castanho
- Portuguese Institute for the Sea and Atmosphere - IPMA, Aquaculture Research Station - EPPO, Olhão, Portugal
| | - Ana Candeias-Mendes
- Portuguese Institute for the Sea and Atmosphere - IPMA, Aquaculture Research Station - EPPO, Olhão, Portugal
| | - Pedro Pousão-Ferreira
- Portuguese Institute for the Sea and Atmosphere - IPMA, Aquaculture Research Station - EPPO, Olhão, Portugal
| | - Ana M Faria
- MARE-Marine and Environmental Sciences Centre, ARNET-Aquatic Research Infrastructure Network Associate Laboratory, ISPA-Instituto Universitário, Rua Jardim Do Tabaco 34, 1149-041, Lisbon, Portugal
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7
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Abdul Azeez S, Gireeshkumar TR, Muraleedharan KR, Vignesh ER, Jaleel AKU, Arya KS, Ravikumar Nair C, Ratheesh R. Factors influencing nearshore hypoxia in the southeastern Arabian Sea: A sensor-based study. MARINE POLLUTION BULLETIN 2023; 197:115696. [PMID: 37897966 DOI: 10.1016/j.marpolbul.2023.115696] [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: 06/18/2023] [Revised: 10/16/2023] [Accepted: 10/18/2023] [Indexed: 10/30/2023]
Abstract
Seasonal upwelling and the associated incursion of hypoxic waters into the coastal zone is a widely studied topic over different upwelling zones. However, its persistence or variations over short time scales are poorly addressed. The present study, therefore, brings out a first report on hourly variations in the temperature, salinity and dissolved oxygen recorded by an environmental data buoy equipped with sensors, deployed in the nearshore waters of Alappuzha (southeastern Arabian Sea) from April to August 2022. The characteristic feature of the Alappuzha coast is the development of mud banks during the southwest monsoon, providing a tranquil environment suitable for continuous sensor-based measurements when the sea remains turbulent elsewhere. The results showed that despite an advance in the upwelling intensity, there is a significant variation in the oxygen concentration in the study domain on a diurnal scale. In general, the nearshore region was under hypoxia during the first half of the day (00:00 to 12:00 h), which increased steadily to reach normoxic and supersaturated levels during the rest of the day (12:00 to 24:00 h). Statistical analysis showed that winds significantly correlate to the coastal environment's subsurface oxygen concentration. During the morning hours, the wind was weak, and the water column remained stratified over the subsurface hypoxic water layer. The situation changed in the afternoon (12:00 h onwards), as there was a steady increase in the local wind speed (>5 m/s), which was sustained during the rest of the day. A local wind speed >5 m/s can disturb the stratification and enhance the mixing process from 12:00 to 24:00 h. The total kinetic energy of 11.5 J/m3 is the threshold for this oxygen supersaturation. These findings emphasize the role of wind-induced mixing in alleviating coastal hypoxia, highlighting the need for further biogeochemical and ecological investigations into the impacts of alternating oxic-hypoxic conditions in nearshore waters.
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Affiliation(s)
- S Abdul Azeez
- CSIR - National Institute of Oceanography, Regional Centre, 31261, Kochi 682 018, India
| | - T R Gireeshkumar
- CSIR - National Institute of Oceanography, Regional Centre, 31261, Kochi 682 018, India.
| | - K R Muraleedharan
- CSIR - National Institute of Oceanography, Regional Centre, 31261, Kochi 682 018, India
| | - E R Vignesh
- CSIR - National Institute of Oceanography, Regional Centre, 31261, Kochi 682 018, India; Cochin University of Science and Technology, India
| | - A K U Jaleel
- CSIR - National Institute of Oceanography, Regional Centre, 31261, Kochi 682 018, India
| | - K S Arya
- CSIR - National Institute of Oceanography, Regional Centre, 31261, Kochi 682 018, India; Cochin University of Science and Technology, India
| | - C Ravikumar Nair
- CSIR - National Institute of Oceanography, Regional Centre, 31261, Kochi 682 018, India
| | - R Ratheesh
- Geo Sciences Division, Space Applications Centre, ISRO, Ahmedabad, India
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8
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Puri D, Sihag P, Thakur M. A Review: Aeration Efficiency of Hydraulic Structures in Diffusing DO in Water. MethodsX 2023; 10:102092. [PMID: 37007614 PMCID: PMC10050780 DOI: 10.1016/j.mex.2023.102092] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 02/20/2023] [Indexed: 03/11/2023] Open
Abstract
This paper contemplates the review of aeration efficiency with commonly used different aeration systems such as Venturi flumes, Weirs, Conduits, Stepped channels, In Venturi Aeration, the SAE value grows fast with the number of air holes. In Weir Aeration, it was found that among all the different labyrinth weir structure, triangular notch weirs are known for the optimum results for air entrainment. The ANN model was developed with parameters discharge (Q) and tail water depth (Tw) which showed that Q is more influential parameter than Tw. In conduits structure, it was found that circular high head gated conduits have better aeration performance than other conduits. Aeration efficiency in Stepped channels cascades may range from 30% to 70%. The sensitivity analysis with ANN model showed that discharge (Q) followed by number of steps (N) was the most influential parameter in E20. Bubble size was the important parameter to undertake when using bubble diffuser. The oxygen transfer efficiency (OTE) in jet diffusers was predicted developing an ANN model. It was found in sensitivity analysis that the input of 'velocity' is highly sensitive to OTE. According to literature, jets can provide OTE in the range of 1.91- 21.53kgO2/kW-hr.
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Affiliation(s)
- Diksha Puri
- School of Environmental Sciences, Shoolini University, Solan, Himachal Pradesh 173229, India
| | - Parveen Sihag
- Department of Civil Engineering, Chandigarh University, Punjab 140301, India
- Corresponding author.
| | - M.S. Thakur
- Professor, Department of Civil Engineering, Shoolini University, Solan, Himachal Pradesh 173229, India
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9
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Heran T, Laudien J, Waller RG, Häussermann V, Försterra G, González HE, Richter C. Life cycle of the cold-water coral Caryophyllia huinayensis. Sci Rep 2023; 13:2593. [PMID: 36788320 PMCID: PMC9929098 DOI: 10.1038/s41598-023-29620-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 02/07/2023] [Indexed: 02/16/2023] Open
Abstract
Little is known about the biology of cold-water corals (CWCs), let alone the reproduction and early life stages of these important deep-sea foundation species. Through a three-year aquarium experiment, we described the reproductive mode, larval release periodicity, planktonic stage, larval histology, metamorphosis and post-larval development of the solitary scleractinian CWC Caryophyllia (Caryophyllia) huinayensis collected in Comau Fjord, Chilean Patagonia. We found that C. huinayensis is a brooder releasing 78.4 ± 65.9 (mean ± standard deviation [SD]) planula larvae throughout the year, a possible adaptation to low seasonality. Planulae had a length of 905 ± 114 µm and showed a well-developed gastrovascular system. After 8 ± 9.3 days (d), the larvae settled, underwent metamorphosis and developed the first set of tentacles after 2 ± 1.5 d. Skeletogenesis, zooplankton feeding and initiation of the fourth set of tentacles started 5 ± 2.1 d later, 21 ± 12.9 d, and 895 ± 45.9 d after settlement, respectively. Our study shows that the ontogenetic timing of C. huinayensis is comparable to that of some tropical corals, despite lacking zooxanthellae.
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Affiliation(s)
- Thomas Heran
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Alten Hafen 26, 27568, Bremerhaven, Germany.
- University of Bremen, Bibliothekstraße 1, 28359, Bremen, Germany.
- Fundación San Ignacio del Huinay, Casilla 462, Puerto Montt, Chile.
| | - Jürgen Laudien
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Alten Hafen 26, 27568, Bremerhaven, Germany
| | - Rhian G Waller
- Tjärnö Marine Laboratory, University of Gothenburg, 452 96, Strömstad, Sweden
| | - Verena Häussermann
- Fundación San Ignacio del Huinay, Casilla 462, Puerto Montt, Chile
- Facultad de Ciencias de la naturaleza, Escuela de Ingeniería en Gestión de Expediciones y Ecoturismo, Universidad San Sebastián, Lago Panguipulli, 1390, Puerto Montt, Chile
| | - Günter Försterra
- Facultad de Recursos Naturales, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso (PUCV), Avda. Brasil, 2950, Valparaíso, Chile
| | - Humberto E González
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Research Center: Dynamics of High Latitude Marine Ecosystems (FONDAP-IDEAL), Valdivia, Chile
| | - Claudio Richter
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Alten Hafen 26, 27568, Bremerhaven, Germany
- University of Bremen, Bibliothekstraße 1, 28359, Bremen, Germany
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10
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Multistressor global change drivers reduce hatch and viability of Lingcod embryos, a benthic egg layer in the California Current System. Sci Rep 2022; 12:21987. [PMID: 36539443 PMCID: PMC9768118 DOI: 10.1038/s41598-022-25553-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022] Open
Abstract
Early life history stages of marine fishes are often more susceptible to environmental stressors than adult stages. This vulnerability is likely exacerbated for species that lay benthic egg masses bound to substrate because the embryos cannot evade locally unfavorable environmental conditions. Lingcod (Ophiodon elongatus), a benthic egg layer, is an ecologically and economically significant predator in the highly-productive California Current System (CCS). We ran a flow-through mesocosm experiment that exposed Lingcod eggs collected from Monterey Bay, CA to conditions we expect to see in the central CCS by the year 2050 and 2100. Exposure to temperature, pH, and dissolved oxygen concentrations projected by the year 2050 halved the successful hatch of Lingcod embryos and significantly reduced the size of day-1 larvae. In the year 2100 treatment, viable hatch plummeted (3% of normal), larvae were undersized (83% of normal), yolk reserves were exhausted (38% of normal), and deformities were widespread (94% of individuals). This experiment is the first to expose marine benthic eggs to future temperature, pH, and dissolved oxygen conditions in concert. Lingcod are a potential indicator species for other benthic egg layers for which global change conditions may significantly diminish recruitment rates.
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11
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Quillen K, Santos N, Testa JM, Woodland RJ. Coastal hypoxia reduces trophic resource coupling and alters niche characteristics of an ecologically dominant omnivore. FOOD WEBS 2022. [DOI: 10.1016/j.fooweb.2022.e00252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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12
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Guo Y, Wu C, Sun J. Pathogenic bacteria significantly increased under oxygen depletion in coastal waters: A continuous observation in the central Bohai Sea. Front Microbiol 2022; 13:1035904. [DOI: 10.3389/fmicb.2022.1035904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 10/19/2022] [Indexed: 11/22/2022] Open
Abstract
The spread of pathogenic bacteria in coastal waters endangers the health of the local people and jeopardizes the safety of the marine environment. However, their dynamics during seasonal hypoxia in the Bohai Sea (BHS) have not been studied. Here, pathogenic bacteria were detected from the 16S rRNA gene sequencing database and were used to explore their dynamics and driving factors with the progressively deoxygenating in the BHS. Our results showed that pathogenic bacteria were detected in all samples, accounting for 0.13 to 24.65% of the total number of prokaryotic sequences in each sample. Pathogenic Proteobacteria was dominated in all samples, followed by Firmicutes, Actinobacteria, Tenericutes, and Bacteroidetes, etc. β-diversity analysis showed that pathogenic bacteria are highly temporally heterogeneous and regulated by environmental factors. According to RDA analysis, these variations may be influenced by salinity, ammonia, DO, phosphate, silicate, and Chl a. Additionally, pathogenic bacteria in surface water and hypoxia zone were found to be significantly separated in August. The vertical distribution of pathogenic bacterial communities is influenced by several variables, including DO and nutrition. It is noteworthy that the hypoxia zones increase the abundance of certain pathogenic genera, especially Vibrio and Arcobacter, and the stability of the pathogenic bacterial community increased from May to August. These phenomena indicate that the central Bohai Sea is threatened by an increasingly serious pathogenic community from May to August. And the developing hypoxia zone in the future may intensify this phenomenon and pose a more serious threat to human health. This study provides new insight into the changes of pathogenic bacteria in aquatic ecosystems and may help to make effective policies to control the spread of pathogenic bacteria.
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Lovecchio E, Henson S, Carvalho F, Briggs N. Oxygen Variability in the Offshore Northern Benguela Upwelling System From Glider Data. JOURNAL OF GEOPHYSICAL RESEARCH. OCEANS 2022; 127:e2022JC019063. [PMID: 36589533 PMCID: PMC9788292 DOI: 10.1029/2022jc019063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/17/2022] [Accepted: 10/20/2022] [Indexed: 06/17/2023]
Abstract
Despite their role in modulating the marine ecosystem, variability and drivers of low-oxygen events in the offshore northern Benguela Upwelling System (BenUS) have been rarely investigated due to the events' episodicity which is difficult to resolve using shipboard measurements. We address this issue using 4 months of high-resolution glider data collected between February and June 2018, 100 km offshore at 18°S. We find that oxygen (O2) concentrations in the offshore northern Benguela are determined by the subsurface alternation of low-oxygen Angola-derived water and oxygenated water from the south at 100-500 m depth. We observe intermittent hypoxia (O2 < 60 μmol kg-1) which occurs on average for ∼30% of the 4 months deployment and is driven by the time-varying subsurface pulses of Angola-derived tropical water. Hypoxic events are rather persistent at depths of 300-450 m, while they are more sporadic and have weekly duration at shallower depths (100-300 m). We find extreme values of hypoxia, with O2 minima of 16 μmol kg-1, associated with an anticyclonic eddy spinning from the undercurrent flowing on the BenUS shelf and showing no surface signature. Fine-scale patchiness and water mass mixing are associated with cross-frontal stirring by a large anticyclone recirculating tropical water into the northern BenUS. The dominance of physical drivers and their high variability on short time scales reveal a dynamic coupling between Angola and Benguela, calling for long-term and high-resolution measurements and studies focusing on future changes of both tropical O2 minima and lateral fluxes in this region.
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Affiliation(s)
| | | | | | - Nathan Briggs
- National Oceanography CentreEuropean WaySouthamptonUK
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14
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M K VS, Joseph S, P S A, Ghermandi A, Kumar A. A coastal Ramsar site on transition to hypoxia and tracking pollution sources: a case study of south-west coast of India. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 195:45. [PMID: 36305948 DOI: 10.1007/s10661-022-10602-x] [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: 05/10/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
Coastal lakes and estuaries are considered economic drivers for coastal communities by delivering invaluable economic and ecosystem services. The coastal ecosystems are facing recurrent hypoxia events (dissolved oxygen; DO < 2.0 mg L-1) and are emerging as a major threat to ecosystem structure and functioning. The Ashtamudi Lake, (area = 56 km2), is one of the Ramsar sites in the State of Kerala and located on the SW coast of India. The waterways are extensively used for backwater tourism and for fishery activities. This paper discusses the spatio-temporal variation of water quality attributes with emphasis on hypoxia during non-monsoon and monsoon seasons. The extent of hypoxia on fishery diversity was discussed. The Southern Zone, adjacent to the urban area, shows the hypoxic condition with higher concentration of BOD, NO3-N, and NH4-N. The hypoxic condition is largely limited to the Southern Zone in both seasons. The occurrence of low DO in the lake is highly related to salinity and organic load in the lake system. The tracking of pollution sources in the lake system was also done through identification of pollution potential zones and found that catchments adjacent to Southern and Western Zones (urban regions) are the major source of pollution. The study suggests that hypoxia is chiefly attributed to anthropogenic interventions in the form of discharge of wastes into the lake causing overloading of nutrients and organic effluents, decrease in the freshwater supply, the absence of proper freshwater mixing or dilution, and effluent discharge from nearby urban centers.
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Affiliation(s)
- Vishnu Sagar M K
- Department of Environmental Sciences, University of Kerala, Thiruvananthapuram, Kerala, India, 695581
| | - Sabu Joseph
- Department of Environmental Sciences, University of Kerala, Thiruvananthapuram, Kerala, India, 695581.
| | - Arunkumar P S
- Department of Environmental Sciences, University of Kerala, Thiruvananthapuram, Kerala, India, 695581
| | - Andrea Ghermandi
- Department of Natural Resources and Environmental Management, University of Haifa, Haifa, Israel
| | - Amit Kumar
- School of Hydrology and Water Resources, Nanjing University of Information Science and Technology, Nanjing, 210044, China
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15
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Kim HH, Vaidya B, Cho SY, Kwon J, Kim D. Anti-hyperglycemic potential of alginate oligosaccharide in a high glucose-induced zebrafish model. J Funct Foods 2022. [DOI: 10.1016/j.jff.2022.105098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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16
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Frankel LT, Friedrichs MAM, St-Laurent P, Bever AJ, Lipcius RN, Bhatt G, Shenk GW. Nitrogen reductions have decreased hypoxia in the Chesapeake Bay: Evidence from empirical and numerical modeling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 814:152722. [PMID: 34974013 DOI: 10.1016/j.scitotenv.2021.152722] [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: 09/19/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
Seasonal hypoxia is a characteristic feature of the Chesapeake Bay due to anthropogenic nutrient input from agriculture and urbanization throughout the watershed. Although coordinated management efforts since 1985 have reduced nutrient inputs to the Bay, oxygen concentrations at depth in the summer still frequently fail to meet water quality standards that have been set to protect critical estuarine living resources. To quantify the impact of watershed nitrogen reductions on Bay hypoxia during a recent period including both average discharge and extremely wet years (2016-2019), this study employed both statistical and three-dimensional (3-D) numerical modeling analyses. Numerical model results suggest that if the nitrogen reductions since 1985 had not occurred, annual hypoxic volumes (O2 < 3 mg L-1) would have been ~50-120% greater during the average discharge years of 2016-2017 and ~20-50% greater during the wet years of 2018-2019. The effect was even greater for O2 < 1 mg L-1, where annual volumes would have been ~80-280% greater in 2016-2017 and ~30-100% greater in 2018-2019. These results were supported by statistical analysis of empirical data, though the magnitude of improvement due to nitrogen reductions was greater in the numerical modeling results than in the statistical analysis. This discrepancy is largely accounted for by warming in the Bay that has exacerbated hypoxia and offset roughly 6-34% of the improvement from nitrogen reductions. Although these results may reassure policymakers and stakeholders that their efforts to reduce hypoxia have improved ecosystem health in the Bay, they also indicate that greater reductions are needed to counteract the ever-increasing impacts of climate change.
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Affiliation(s)
- Luke T Frankel
- Virginia Institute of Marine Science, William & Mary, 1370 Greate Road, Gloucester Point, VA, USA.
| | - Marjorie A M Friedrichs
- Virginia Institute of Marine Science, William & Mary, 1370 Greate Road, Gloucester Point, VA, USA
| | - Pierre St-Laurent
- Virginia Institute of Marine Science, William & Mary, 1370 Greate Road, Gloucester Point, VA, USA
| | - Aaron J Bever
- Anchor QEA LLC, 1201 3rd Avenue, Suite 2600, Seattle, WA, USA
| | - Romuald N Lipcius
- Virginia Institute of Marine Science, William & Mary, 1370 Greate Road, Gloucester Point, VA, USA
| | - Gopal Bhatt
- Chesapeake Bay Program Office, 1750 Forest Drive, Suite 130, Annapolis, MD, USA; Department of Civil & Environmental Engineering, The Pennsylvania State University, 212 Sackett Building, University Park, PA, USA
| | - Gary W Shenk
- Chesapeake Bay Program Office, 1750 Forest Drive, Suite 130, Annapolis, MD, USA; U.S. Geological Survey, Virginia and West Virginia Water Science Center, 1730 East Parham Road, Richmond, VA, USA
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17
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Comparative transcriptome analysis provides novel insights into the molecular mechanism of the silver carp (Hypophthalmichthys molitrix) brain in response to hypoxia stress. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2022; 41:100951. [PMID: 34923202 DOI: 10.1016/j.cbd.2021.100951] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/06/2021] [Accepted: 12/08/2021] [Indexed: 02/05/2023]
Abstract
The brain of fish plays an important role in regulating growth and adapting to environmental changes. However, few studies have been performed to address the changes in gene expression profiles in fish brains under hypoxic stress. In the present study, silver carp (Hypophthalmichthys molitrix) were kept under hypoxic experimental conditions by using the method of natural oxygen consumption, which resulted in a significant decrease in malondialdehyde (MDA) and glutathione (GSH) content and superoxide dismutase (SOD) activity in the brain. In addition, RNA sequencing (RNA-Seq) was performed to analyze transcriptional regulation in the brains of silver carp under normoxia (control group), hypoxia, semi-asphyxia, and asphyxia conditions. The results of KEGG enrichment pathway analysis showed that the immune system, such as antigen processing and presentation, natural killer cell-mediated cytotoxicity, was enriched in the hypoxia group; the nervous system (e.g., "glutamatergic synapse"), signal transduction (e.g., "calcium signaling pathway"; "foxo signaling pathway"), and signaling molecules and interactions (e.g., "neuroactive ligand-receptor interaction") were enriched in the semi-asphyxia group; and signaling molecules and interactions (e.g., "neuroactive ligand-receptor interaction") were enriched in the asphyxia group. These results provide novel insights into the molecular regulatory mechanism of the fish brain coping with hypoxia stress.
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18
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Orio A, Heimbrand Y, Limburg K. Deoxygenation impacts on Baltic Sea cod: Dramatic declines in ecosystem services of an iconic keystone predator. AMBIO 2022; 51:626-637. [PMID: 34075555 PMCID: PMC8800964 DOI: 10.1007/s13280-021-01572-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/07/2021] [Accepted: 05/03/2021] [Indexed: 06/12/2023]
Abstract
The intensified expansion of the Baltic Sea's hypoxic zone has been proposed as one reason for the current poor status of cod (Gadus morhua) in the Baltic Sea, with repercussions throughout the food web and on ecosystem services. We examined the links between increased hypoxic areas and the decline in maximum length of Baltic cod, a demographic proxy for services generation. We analysed the effect of different predictors on maximum length of Baltic cod during 1978-2014 using a generalized additive model. The extent of minimally suitable areas for cod (oxygen concentration ≥ 1 ml l-1) is the most important predictor of decreased cod maximum length. We also show, with simulations, the potential for Baltic cod to increase its maximum length if hypoxic areal extent is reduced to levels comparable to the beginning of the 1990s. We discuss our findings in relation to ecosystem services affected by the decrease of cod maximum length.
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Affiliation(s)
- Alessandro Orio
- Department of Aquatic Resources, Institute of Marine Research, Swedish University of Agricultural Sciences, Turistgatan 5, 453 30 Lysekil, Sweden
| | - Yvette Heimbrand
- Department of Aquatic Resources, Institute of Coastal Research, Swedish University of Agricultural Sciences, Skolgatan 6, 742 42 Öregrund, Sweden
| | - Karin Limburg
- Department of Aquatic Resources, Institute of Marine Research, Swedish University of Agricultural Sciences, Turistgatan 5, 453 30 Lysekil, Sweden
- College of Environmental Science and Forestry, State University of New York, Syracuse, NY USA
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19
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20
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Adyasari D, Pratama MA, Teguh NA, Sabdaningsih A, Kusumaningtyas MA, Dimova N. Anthropogenic impact on Indonesian coastal water and ecosystems: Current status and future opportunities. MARINE POLLUTION BULLETIN 2021; 171:112689. [PMID: 34256325 DOI: 10.1016/j.marpolbul.2021.112689] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 06/22/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
Indonesia, the world's largest archipelagic country and the fourth most populated nation, has struggled with coastal water pollution in the last decades. With the increasing population in coastal urban cities, more land-based pollutants are transported to the coastal water and adversely affected the tropical ecosystems. This paper provides an overview of anthropogenic pollutant studies in Indonesian coastal water and ecosystems from 1986 to 2021. Nutrients, heavy metals, organic pollutants, and plastic debris are the most-studied contaminants. We found that 82%, 54% and 50% of the studies exceeding nutrients, heavy metals, and organic pollutants standard limit, respectively; thus, indicating poor water quality status in part of Indonesian coastal water. The coral reef ecosystems is found to be the most sensitive to anthropogenic disturbance. The potential effect of climate change, new coastal pollution hotspots in eastern Indonesia, marine anthropogenic sources, legacy/emerging pollutants, and the need for research related to the biological contamination, are discussed for future opportunities.
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Affiliation(s)
- Dini Adyasari
- Department of Geological Sciences, University of Alabama, Tuscaloosa 35487, USA.
| | | | - Novi Andriany Teguh
- Department of Civil Engineering, Sepuluh Nopember Institute of Technology, Surabaya 60111, Indonesia
| | - Aninditia Sabdaningsih
- Department of Aquatic Resources, Faculty of Fisheries and Marine Sciences, Diponegoro University, Semarang 50275, Indonesia; Tropical Marine Biotechnology Laboratory, Faculty of Fisheries and Marine Sciences, Diponegoro University, Semarang 50275, Indonesia
| | | | - Natasha Dimova
- Department of Geological Sciences, University of Alabama, Tuscaloosa 35487, USA
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21
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Knowledge of, and Attitudes towards, Live Fish Transport among Aquaculture Industry Stakeholders in China: A Qualitative Study. Animals (Basel) 2021; 11:ani11092678. [PMID: 34573646 PMCID: PMC8466337 DOI: 10.3390/ani11092678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 08/21/2021] [Accepted: 09/01/2021] [Indexed: 01/26/2023] Open
Abstract
Simple Summary China is the world’s largest producer of food fish, and Chinese consumers have a preference to buy live fish. Live transport of fish is, therefore, a common procedure in aquaculture and is a potential animal welfare hazard. Little has been published on current fish transportation practices in China or the knowledge and attitudes of stakeholders in this industry. Our qualitative study aimed to obtain original information about live transport processes from a cross-section of aquaculture stakeholders in China by conducting individual interviews. Stakeholders were interviewed about their knowledge of live transport and their attitudes towards the welfare of fish. Self-described knowledge of live transport varied between participants with different job types. Most participants had heard of and understood the concept of “animal welfare”, but many understood it to only refer to terrestrial livestock, not fish. This suggests that knowledge of fish welfare in the industry may be less than for other farm animals. The findings of this pilot study contribute to a better understanding of live fish transport from a stakeholder point of view. The findings will also assist in informing, educating, and sensitizing stakeholders to the importance of fish welfare during live transport. Abstract China is the largest food fish producer in the world. Chinese consumers normally purchase fish that are still alive to ensure freshness. Therefore, the live transport of fish is important in China’s aquaculture, although it carries potential risks for animal welfare. This study investigated the attitudes and knowledge of stakeholders within Chinese aquaculture towards the live transport and welfare of fish. Semi-structured interviews were conducted with 12 participants who were involved with the aquaculture industry in China. Most participants self-rated their transport-related knowledge as moderate and had some understanding of animal welfare, although this term was generally considered only relevant to terrestrial animals. Participants’ responses indicated that the live transport of fish occurs frequently in China, generally using sealed tanks, plastic bags, and foam boxes, in purpose-built vehicles. Seasonal changes, such as changes in ambient and water temperature, are considered to be important contributors to successful live transport, as well as sufficient oxygen supplies and stocking density. The use of anesthetics was not commonly reported, particularly in food fish, and fish capture is predominantly by conventional dipnets. The health status of transported fish is determined mostly by morphology (body injury, body or eye color, and fin condition), as well as vigor and swimming ability. Our results indicate that live transport poses a number of welfare risks to fish but that participants in the process associated welfare concerns more with terrestrial animals, not fish.
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22
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Variable coastal hypoxia exposure and drivers across the southern California Current. Sci Rep 2021; 11:10929. [PMID: 34035327 PMCID: PMC8149850 DOI: 10.1038/s41598-021-89928-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 04/26/2021] [Indexed: 02/04/2023] Open
Abstract
Declining oxygen is one of the most drastic changes in the ocean, and this trend is expected to worsen under future climate change scenarios. Spatial variability in dissolved oxygen dynamics and hypoxia exposures can drive differences in vulnerabilities of coastal ecosystems and resources, but documentation of variability at regional scales is rare in open-coast systems. Using a regional collaborative network of dissolved oxygen and temperature sensors maintained by scientists and fishing cooperatives from California, USA, and Baja California, Mexico, we characterize spatial and temporal variability in dissolved oxygen and seawater temperature dynamics in kelp forest ecosystems across 13° of latitude in the productive California Current upwelling system. We find distinct latitudinal patterns of hypoxia exposure and evidence for upwelling and respiration as regional drivers of oxygen dynamics, as well as more localized effects. This regional and small-scale spatial variability in dissolved oxygen dynamics supports the use of adaptive management at local scales, and highlights the value of collaborative, large-scale coastal monitoring networks for informing effective adaptation strategies for coastal communities and fisheries in a changing climate.
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23
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Steube TR, Altenritter ME, Walther BD. Distributive stress: individually variable responses to hypoxia expand trophic niches in fish. Ecology 2021; 102:e03356. [PMID: 33811651 PMCID: PMC8244237 DOI: 10.1002/ecy.3356] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 01/05/2021] [Accepted: 02/05/2021] [Indexed: 01/18/2023]
Abstract
Environmental stress can reshape trophic interactions by excluding predators or rendering prey vulnerable, depending on the relative sensitivity of species to the stressor. Classical models of food web responses to stress predict either complete predator exclusion from stressed areas or complete prey vulnerability if predators are stress tolerant. However, if the consumer response to the stress is individually variable, the result may be a distributive stress model (DSM) whereby predators distribute consumption pressure across a range of prey guilds and their trophic niche is expanded. We test these models in one of the largest hypoxic “Dead Zones” in the world, the northern Gulf of Mexico, by combining geochemical tracers of hypoxia exposure and isotope ratios to assess individual‐level trophic responses. Hypoxia‐exposed fish occupied niche widths that were 14.8% and 400% larger than their normoxic counterparts in two different years, consistent with variable displacement from benthic to pelagic food webs. The degree of isotopic displacement depended on the magnitude of hypoxia exposure. These results are consistent with the DSM and highlight the need to account for individually variable sublethal effects when predicting community responses to environmental stress.
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Affiliation(s)
- Tyler R Steube
- Department of Life Sciences, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, Texas, 78412, USA
| | - Matthew E Altenritter
- Department of Life Sciences, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, Texas, 78412, USA.,Department of Environmental Science & Ecology, The College at Brockport, State University of New York, 350 New Campus Drive, Brockport, New York, 14420, USA
| | - Benjamin D Walther
- Department of Life Sciences, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, Texas, 78412, USA
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Joachim S, Beaudouin R, Daniele G, Geffard A, Bado-Nilles A, Tebby C, Palluel O, Dedourge-Geffard O, Fieu M, Bonnard M, Palos-Ladeiro M, Turiès C, Vulliet E, David V, Baudoin P, James A, Andres S, Porcher JM. Effects of diclofenac on sentinel species and aquatic communities in semi-natural conditions. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 211:111812. [PMID: 33472112 DOI: 10.1016/j.ecoenv.2020.111812] [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: 07/06/2020] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 05/14/2023]
Abstract
Due to the potential hazard of diclofenac on aquatic organisms and the lack of higher-tier ecotoxicological studies, a long-term freshwater mesocosm experiment was set up to study the effects of this substance on primary producers and consumers at environmentally realistic nominal concentrations 0.1, 1 and 10 µg/L (average effective concentrations 0.041, 0.44 and 3.82 µg/L). During the six-month exposure period, the biovolume of two macrophyte species (Nasturtium officinale and Callitriche platycarpa) significantly decreased at the highest treatment level. Subsequently, a decrease in dissolved oxygen levels was observed. High mortality rates, effects on immunity, and high genotoxicity were found for encaged zebra mussels (Dreissena polymorpha) in all treatments. In the highest treatment level, one month after the beginning of the exposure, mortality of adult fish (Gasterosteus aculeatus) caused effects on the final population structure. Total abundance of fish and the percentage of juveniles decreased whereas the percentage of adults increased. This led to an overall shift in the length frequency distribution of the F1 generation compared to the control. Consequently, indirect effects on the community structure of zooplankton and macroinvertebrates were observed in the highest treatment level. The No Observed Effect Concentration (NOEC) value at the individual level was < 0.1 µg/L and 1 µg/L at the population and community levels. Our study showed that in more natural conditions, diclofenac could cause more severe effects compared to those observed in laboratory conditions. The use of our results for regulatory matters is also discussed.
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Affiliation(s)
- S Joachim
- Unité d'écotoxicologie in vitro et in vivo(ECOT)/UMR-I 02 SEBIO, INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte,France.
| | - R Beaudouin
- Unit of Models for Ecotoxicology and Toxicology (METO), INERIS, 60550 Verneuil-en-Halatte, France
| | - G Daniele
- Univ Lyon, CNRS, Université Claude Bernard Lyon 1, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100 Villeurbanne, France
| | - A Geffard
- Université de Reims Champagne Ardenne, UMR-I 02 SEBIO, Moulin de la Housse BP 1039, 51687 Reims
| | - A Bado-Nilles
- Unité d'écotoxicologie in vitro et in vivo(ECOT)/UMR-I 02 SEBIO, INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte,France
| | - C Tebby
- Unit of Models for Ecotoxicology and Toxicology (METO), INERIS, 60550 Verneuil-en-Halatte, France
| | - O Palluel
- Unité d'écotoxicologie in vitro et in vivo(ECOT)/UMR-I 02 SEBIO, INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte,France
| | - O Dedourge-Geffard
- Université de Reims Champagne Ardenne, UMR-I 02 SEBIO, Moulin de la Housse BP 1039, 51687 Reims
| | - M Fieu
- Univ Lyon, CNRS, Université Claude Bernard Lyon 1, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100 Villeurbanne, France
| | - M Bonnard
- Université de Reims Champagne Ardenne, UMR-I 02 SEBIO, Moulin de la Housse BP 1039, 51687 Reims
| | - M Palos-Ladeiro
- Université de Reims Champagne Ardenne, UMR-I 02 SEBIO, Moulin de la Housse BP 1039, 51687 Reims
| | - C Turiès
- Unité d'écotoxicologie in vitro et in vivo(ECOT)/UMR-I 02 SEBIO, INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte,France
| | - E Vulliet
- Univ Lyon, CNRS, Université Claude Bernard Lyon 1, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100 Villeurbanne, France
| | - V David
- Unit of Models for Ecotoxicology and Toxicology (METO), INERIS, 60550 Verneuil-en-Halatte, France
| | - P Baudoin
- Unité d'écotoxicologie in vitro et in vivo(ECOT)/UMR-I 02 SEBIO, INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte,France
| | - A James
- Expertise entoxicologie/écotoxicologie des substances chimiques (ETES), INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte, France
| | - S Andres
- Expertise entoxicologie/écotoxicologie des substances chimiques (ETES), INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte, France
| | - J M Porcher
- Unité d'écotoxicologie in vitro et in vivo(ECOT)/UMR-I 02 SEBIO, INERIS, Parc ALATA, BP2, 60550 Verneuil-en-Halatte,France
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Resequencing and SNP discovery of Amur ide (Leuciscus waleckii) provides insights into local adaptations to extreme environments. Sci Rep 2021; 11:5064. [PMID: 33658614 PMCID: PMC7930030 DOI: 10.1038/s41598-021-84652-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 02/18/2021] [Indexed: 01/31/2023] Open
Abstract
Amur ide (Leuciscus waleckii), a Cyprinid species, is broadly distributed in Northeast Asia. Different from its freshwater counterparts, the population in Lake Dali Nor has a strong alkalinity tolerance and can adapt to extremely alkali-saline water with bicarbonate over 50 mmol/L. To uncover the genetic basis of its alkaline adaptation, three populations, including one alkali form from Lake Dali Nor (DL), one freshwater form from its adjacent sister Lake Ganggeng Nor (GG), and one freshwater form from its historical origin, namely, the Songhua River (SH), were analyzed using genome resequencing technology. A total of 679.82 Gb clean data and 38,091,163 high-quality single-nucleotide polymorphism (SNP) loci were detected in the three populations. Nucleotide diversity and population structure analysis revealed that the DL and GG populations have lower nucleotide diversities and different genetic structures than those of the SH population. Selective sweeping showed 21 genes involved in osmoregulatory regulation (DLG1, VIPR1, AKT1, and GNAI1), inflammation and immune responses (DLG1, BRINP1, CTSL, TRAF6, AKT1, STAT3, GNAI1, SEC22b, and PSME4b), and cardiorespiratory development (TRAF6, PSME4b, STAT3, AKT1, and COL9A1) to be associated with alkaline adaption of the DL population. Interestingly, selective pressure (CodeML, MEME, and FEL) methods identified two functional codon sites of VIPR1 to be under positive selection in the DL population. The subsequent 3D protein modeling confirmed that these selected sites will incur changes in protein structure and function in the DL population. In brief, this study provides molecular evidence of population divergence and alkaline adaptation, which will be very useful for revealing the genetic basis of alkaline adaptation in Amur ide.
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de Carvalho DR, Alves CBM, Moreira MZ, Pompeu PS. Trophic diversity and carbon sources supporting fish communities along a pollution gradient in a tropical river. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:139878. [PMID: 32535283 DOI: 10.1016/j.scitotenv.2020.139878] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/14/2020] [Accepted: 05/30/2020] [Indexed: 06/11/2023]
Abstract
Anthropogenic activities can have a great influence on water quality and in the availability of habitat and food resources, which can promote changes in the trophic diversity and carbon sources sustaining aquatic communities. The objective of this study was to evaluate if the trophic diversity and the main carbon sources sustaining fish communities change along a pollution gradient. The study was carried out at eight sites distributed along the Rio das Velhas, a Brazilian river highly impacted by anthropogenic activities, in which the discharge of domestic and industrial sewage from the Metropolitan Region of Belo Horizonte (MRBH) presents a major source of pollution. Using carbon (δ13C) and nitrogen (δ15N) isotope ratios, we identified the major carbon sources/food sources of common fish species and calculated six metrics of trophic diversity. Autochthonous primary producers (algae, periphyton, and macrophytes) were the main carbon sources for all trophic guilds at all sites, but notably, sewage-derived organic matter was an additional significant carbon source to the fish community in the most polluted testing site. Here, the community was composed mainly by detritivorous and omnivorous fishes and exhibited greater ranges of carbon and nitrogen isotopic values, large total areas, high trophic diversity, small trophic redundancy, and less even distribution of trophic niches than the less polluted sites. We conclude that the trophic guilds, trophic diversity metrics, and carbon sources sustaining fish communities in the Rio das Velhas are highly influenced by the presence of pollution. Besides favoring omnivorous and detritivorous fishes, the input of sewage also provided an important food source to sustain the fish community from sites close to the MRBH.
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Affiliation(s)
- Débora Reis de Carvalho
- Laboratório de Ecologia de Peixes, Setor de Ecologia, Departamento de Biologia, Universidade Federal de Lavras, Campus Universitário, Caixa Postal 3037, CEP 37200-000 Lavras, MG, Brasil.
| | - Carlos Bernardo Mascarenhas Alves
- Laboratório Nuvelhas, Projeto Manuelzão, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, CEP 31270-901 Belo Horizonte, MG, Brasil.
| | - Marcelo Zacharias Moreira
- Laboratório de Ecologia Isotópica, Centro de Energia Nuclear na Agricultura - CENA, Universidade de São Paulo, Av. Centenário, 303, Caixa Postal 96, CEP 13400-970 Piracicaba, SP, Brasil.
| | - Paulo Santos Pompeu
- Laboratório de Ecologia de Peixes, Setor de Ecologia, Departamento de Biologia, Universidade Federal de Lavras, Campus Universitário, Caixa Postal 3037, CEP 37200-000 Lavras, MG, Brasil.
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Lee CW, Lim JH, Heng PL, Marican NF, Narayanan K, Sim EUH, Bong CW. Influence of elevated river flow on hypoxia occurrence, nutrient concentration and microbial dynamics in a tropical estuary. ENVIRONMENTAL MONITORING AND ASSESSMENT 2020; 192:660. [PMID: 32975666 DOI: 10.1007/s10661-020-08625-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 09/20/2020] [Indexed: 06/11/2023]
Abstract
We sampled the Klang estuary during the inter-monsoon and northeast monsoon period (July-Nov 2011, Oct-Nov 2012), which coincided with higher rainfall and elevated Klang River flow. The increased freshwater inflow into the estuary resulted in water column stratification that was observed during both sampling periods. Dissolved oxygen (DO) dropped below 63 μM, and hypoxia was observed. Elevated river flow also transported dissolved inorganic nutrients, chlorophyll a and bacteria to the estuary. However, bacterial production did not correlate with DO concentration in this study. As hypoxia was probably not due to in situ heterotrophic processes, deoxygenated waters were probably from upstream. We surmised this as DO correlated with salinity (R2 = 0.664, df = 86, p < 0.001). DO also decreased with increasing flushing time (R2 = 0.556, df = 11, p < 0.01), suggesting that when flushing time (> 6.7 h), hypoxia could occur at the Klang estuary. Here, we presented a model that related riverine flow rate to the post-heavy rainfall hypoxia that explicated the episodic hypoxia at Klang estuary. As Klang estuary supports aquaculture and cockle culture, our results could help protect the aquaculture and cockle culture industry here.
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Affiliation(s)
- Choon Weng Lee
- Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
- Institute of Ocean and Earth Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Joon Hai Lim
- Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
- Institute of Ocean and Earth Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia
- Institute for Advanced Studies, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Pei Li Heng
- Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Nurul Fitrah Marican
- Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kumaran Narayanan
- School of Science, Monash University Malaysia, Bandar Sunway, 47500, Subang Jaya, Selangor, Malaysia
| | - Edmund Ui Hang Sim
- Faculty of Resource Sciences and Technology, Universiti Malaysia Sarawak, 94300, Kota Samarahan, Sarawak, Malaysia
| | - Chui Wei Bong
- Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
- Institute of Ocean and Earth Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia
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Mattiasen EG, Kashef NS, Stafford DM, Logan CA, Sogard SM, Bjorkstedt EP, Hamilton SL. Effects of hypoxia on the behavior and physiology of kelp forest fishes. GLOBAL CHANGE BIOLOGY 2020; 26:3498-3511. [PMID: 32153086 DOI: 10.1111/gcb.15076] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 02/23/2020] [Indexed: 05/14/2023]
Abstract
Forecasts from climate models and oceanographic observations indicate increasing deoxygenation in the global oceans and an elevated frequency and intensity of hypoxic events in the coastal zone, which have the potential to affect marine biodiversity and fisheries. Exposure to low dissolved oxygen (DO) conditions may have deleterious effects on early life stages in fishes. This study aims to identify thresholds to hypoxia while testing behavioral and physiological responses of two congeneric species of kelp forest fish to four DO levels, ranging from normoxic to hypoxic (8.7, 6.0, 4.1, and 2.2 mg O2 /L). Behavioral tests identified changes in exploratory behavior and turning bias (lateralization), whereas physiological tests focused on determining changes in hypoxia tolerance (pCrit), ventilation rates, and metabolic rates, with impacts on the resulting capacity for aerobic activity. Our findings indicated that copper rockfish (Sebastes caurinus) and blue rockfish (Sebastes mystinus) express sensitivity to hypoxia; however, the strength of the response differed between species. Copper rockfish exhibited reduced absolute lateralization and increased escape time at the lowest DO levels, whereas behavioral metrics for blue rockfish did not vary with oxygen level. Both species exhibited decreases in aerobic scope (as a function of reduced maximum metabolic rate) and increases in ventilation rates to compensate for decreasing oxygen levels. Blue rockfish had a lower pCrit and stronger acclimation response compared to copper rockfish. The differences expressed by each species suggest that acclimatization to changing ocean conditions may vary, even among related species that recruit to the same kelp forest habitat, leading to winners and losers under future ocean conditions. Exposure to hypoxia can decrease individual physiological fitness through metabolic and aerobic depression and changes to anti-predator behavior, with implications for the outcome of ecological interactions and the management of fish stocks in the face of climate change.
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Affiliation(s)
| | - Neosha S Kashef
- Fisheries Ecology Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Santa Cruz, CA, USA
- Marine Science Institute, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - David M Stafford
- Fisheries Ecology Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Santa Cruz, CA, USA
- Marine Science Institute, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Cheryl A Logan
- California State University Monterey Bay, Seaside, CA, USA
| | - Susan M Sogard
- Fisheries Ecology Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Santa Cruz, CA, USA
| | - Eric P Bjorkstedt
- Fisheries Ecology Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Santa Cruz, CA, USA
- Department of Fisheries Biology, Humboldt State University, Trinidad, CA, USA
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Yabsley NA, Gilby BL, Schlacher TA, Henderson CJ, Connolly RM, Maxwell PS, Olds AD. Landscape context and nutrients modify the effects of coastal urbanisation. MARINE ENVIRONMENTAL RESEARCH 2020; 158:104936. [PMID: 32217293 DOI: 10.1016/j.marenvres.2020.104936] [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: 10/07/2019] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 06/10/2023]
Abstract
Estuaries are focal points for coastal cities worldwide, their habitats frequently transformed into engineered shorelines abutting waters with elevated nutrients in an urbanised landscape. Here we test for relationships between shoreline armouring and nutrients on the diversity and trophic composition of fish assemblages across 22 estuaries in eastern Australia. Urbanisation was associated with fish diversity and abundance, but there were differences in the effects of shoreline armouring and nutrient level on the trophic composition of fish assemblages. Fish diversity and the abundance of most trophic groups, particularly omnivores, zoobenthivores and detritivores, was greatest in highly urban estuaries. We show that estuarine fish assemblages are associated with urbanisation in more nuanced ways than simple habitat transformation would suggest, but this depends on the broader environmental context. Our findings have wider implications for estuarine conservation and restoration, emphasizing that ecological benefits of habitat measures may depend on both landscape attributes and water quality in urban settings.
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Affiliation(s)
- Nicholas A Yabsley
- School of Science and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
| | - Ben L Gilby
- School of Science and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
| | - Thomas A Schlacher
- School of Science and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
| | - Christopher J Henderson
- School of Science and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia.
| | - Rod M Connolly
- Australian Rivers Institute- Coasts and Estuaries, School of Environment and Science, Griffith University, Gold Coast, Queensland, 4222, Australia
| | - Paul S Maxwell
- Healthy Land and Water, Level 4, 200 Creek Street, Spring Hill, 4004, Queensland, Australia
| | - Andrew D Olds
- School of Science and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland, 4558, Australia
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Saari GN, Haddad SP, Mole RM, Hill BN, Steele WB, Lovin LM, Chambliss CK, Brooks BW. Low dissolved oxygen increases uptake of a model calcium channel blocker and alters its effects on adult Pimephales promelas. Comp Biochem Physiol C Toxicol Pharmacol 2020; 231:108719. [PMID: 31987992 DOI: 10.1016/j.cbpc.2020.108719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 01/18/2020] [Accepted: 01/21/2020] [Indexed: 10/25/2022]
Abstract
Human population growth accompanied with urbanization is urbanizing the water cycle in many regions. Urban watersheds, particularly with limited upstream dilution of effluent discharges, represent worst case scenarios for exposure to multiple environmental stressors, including down the drain chemicals (e.g., pharmaceuticals) and other stressors (e.g., dissolved oxygen (DO)). We recently identified the calcium channel blocker diltiazem (DZM) to accumulate in fish plasma exceeding human therapeutic doses (e.g., Cmin) in coastal estuaries impaired due to nonattainment of DO water quality standards. Thus, we examined whether DO influences DZM uptake by fish, and if changes in DO-dependent upatke alter fish physiological and biochemical responses. Low DO (3.0 mg DO/L) approximately doubled diltiazem uptake in adult fathead minnows relative to normoxic (8.2 mg DO/L) conditions and were associated with significant (p < 0.05) increases in fish ventilation rate at low DO levels. Decreased burst swim performance (Uburst) of adult fathead minnows were significantly (p < 0.05) altered by low versus normal DO levels. DO × DZM studies reduced Uburst by 13-31% from controls, though not significantly (p = 0.06). Physiological responses in fish exposed to DZM alone were minimal; however, in co-exposure with low DO, decreasing trends in Uburst appeared inversely related to plasma lactate levels. Such physiological responses to multiple stressors, when paired with internal tissue concentrations, identify the utility of employing biological read across approaches to identify adverse outcomes of heart medications and potentially other cardiotoxicants impacting fish cardiovascular function across DO gradients.
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Affiliation(s)
- Gavin N Saari
- Department of Environmental Science, Baylor University, Waco, TX, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | - Samuel P Haddad
- Department of Environmental Science, Baylor University, Waco, TX, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | - Rachel M Mole
- Department of Environmental Science, Baylor University, Waco, TX, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | - Bridgett N Hill
- Department of Environmental Science, Baylor University, Waco, TX, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | - W Baylor Steele
- Department of Environmental Science, Baylor University, Waco, TX, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA; Institute of Biomedical Studies, Baylor University, Waco, TX, USA
| | - Lea M Lovin
- Department of Environmental Science, Baylor University, Waco, TX, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | - C Kevin Chambliss
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA; Department of Chemistry, Baylor University, Waco, TX, USA
| | - Bryan W Brooks
- Department of Environmental Science, Baylor University, Waco, TX, USA; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA; Institute of Biomedical Studies, Baylor University, Waco, TX, USA; School of Environment, Jinan University, Guangzhou, China.
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Fewer Copepods, Fewer Anchovies, and More Jellyfish: How Does Hypoxia Impact the Chesapeake Bay Zooplankton Community? DIVERSITY 2020. [DOI: 10.3390/d12010035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To understand dissolved oxygen deficiency in Chesapeake Bay and its direct impact on zooplankton and planktivorous fish communities, six research cruises were conducted at two sites in the Chesapeake Bay from spring to autumn in 2010 and 2011. Temperature, salinity, and dissolved oxygen were measured from hourly conductivity, temperature, and depth (CTD) casts, and crustacean zooplankton, planktivorous fish and gelatinous zooplankton were collected with nets and trawls. CTD data were grouped into three temperature groups and two dissolved oxygen-level subgroups using principal component analysis (PCA). Species concentrations and copepod nonpredatory mortalities were compared between oxygenated conditions within each temperature group. Under hypoxic conditions, there usually were significantly fewer copepods Acartia tonsa and bay anchovies Anchoa mitchilli, but more bay nettles Chyrsaora chesapeakei and lobate ctenophores Mnemiopsis leidyi. Neutral red staining of copepod samples confirmed that copepod nonpredatory mortalities were higher under hypoxic conditions than under normoxia, indicating that the sudden decline in copepod concentration in summer was directly associated with hypoxia. Because comparisons were made within each temperature group, the effects of temperature were isolated, and hypoxia was clearly shown to have contributed to copepod decreases, planktivorous fish decreases, and gelatinous zooplankton increases. This research quantified the direct effects of hypoxia and explained the interactions between seasonality and hypoxia on the zooplankton population.
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32
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Ziegler SL, Able KW, Fodrie FJ. Dietary shifts across biogeographic scales alter spatial subsidy dynamics. Ecosphere 2019. [DOI: 10.1002/ecs2.2980] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Shelby L. Ziegler
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City North Carolina 28557 USA
| | - Kenneth W. Able
- Rutgers University Marine Field Station Rutgers University Tuckerton New Jersey 08087 USA
| | - F. Joel Fodrie
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City North Carolina 28557 USA
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Cross EL, Murray CS, Baumann H. Diel and tidal pCO 2 × O 2 fluctuations provide physiological refuge to early life stages of a coastal forage fish. Sci Rep 2019; 9:18146. [PMID: 31796762 PMCID: PMC6890771 DOI: 10.1038/s41598-019-53930-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/06/2019] [Indexed: 11/09/2022] Open
Abstract
Coastal ecosystems experience substantial natural fluctuations in pCO2 and dissolved oxygen (DO) conditions on diel, tidal, seasonal and interannual timescales. Rising carbon dioxide emissions and anthropogenic nutrient input are expected to increase these pCO2 and DO cycles in severity and duration of acidification and hypoxia. How coastal marine organisms respond to natural pCO2 × DO variability and future climate change remains largely unknown. Here, we assess the impact of static and cycling pCO2 × DO conditions of various magnitudes and frequencies on early life survival and growth of an important coastal forage fish, Menidia menidia. Static low DO conditions severely decreased embryo survival, larval survival, time to 50% hatch, size at hatch and post-larval growth rates. Static elevated pCO2 did not affect most response traits, however, a synergistic negative effect did occur on embryo survival under hypoxic conditions (3.0 mg L−1). Cycling pCO2 × DO, however, reduced these negative effects of static conditions on all response traits with the magnitude of fluctuations influencing the extent of this reduction. This indicates that fluctuations in pCO2 and DO may benefit coastal organisms by providing periodic physiological refuge from stressful conditions, which could promote species adaptability to climate change.
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Affiliation(s)
- Emma L Cross
- University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, 06340, Groton, CT, USA.
| | - Christopher S Murray
- University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, 06340, Groton, CT, USA
| | - Hannes Baumann
- University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, 06340, Groton, CT, USA
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Thambithurai D, Crespel A, Norin T, Rácz A, Lindström J, Parsons KJ, Killen SS. Hypoxia alters vulnerability to capture and the potential for trait-based selection in a scaled-down trawl fishery. CONSERVATION PHYSIOLOGY 2019; 7:coz082. [PMID: 31803472 PMCID: PMC6880855 DOI: 10.1093/conphys/coz082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 08/29/2019] [Accepted: 09/18/2019] [Indexed: 06/10/2023]
Abstract
Lay summary Selective harvest of wild organisms by humans can influence the evolution of plants and animals, and fishing is recognized as a particularly strong driver of this process. Importantly, these effects occur alongside environmental change. Here we show that aquatic hypoxia can alter which individuals within a fish population are vulnerable to capture by trawling, potentially altering the selection and evolutionary effects stemming from commercial fisheries.
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Affiliation(s)
- Davide Thambithurai
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Amelie Crespel
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Tommy Norin
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
- DTU Aqua: National Institute of Aquatic Resources, Technical University of Denmark, Kemitorvet, Building 202, 2800 Kgs. Lyngby, Denmark
| | - Anita Rácz
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
- Department of Genetics, Eötvös Loránd University, Pázmány P.s. 1C, H-1117 Budapest, Hungary
| | - Jan Lindström
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Kevin J Parsons
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Shaun S Killen
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
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Martínez-Jardines M, Pérez-Alfaro E, González-Robles RO, Texier AC, Cuervo-López F. Decrease of inhibitory effect of 2-chlorophenol on nitrification in sequencing batch reactors. ENVIRONMENTAL TECHNOLOGY 2019; 40:3422-3433. [PMID: 29757088 DOI: 10.1080/09593330.2018.1476594] [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: 01/11/2018] [Accepted: 05/05/2018] [Indexed: 06/08/2023]
Abstract
The metabolic and kinetic behaviour of a nitrification process in the presence of 2-chlorophenol (2-CP) was evaluated in two sequencing batch reactors (SBR1, SBR2) inoculated with nitrifying sludge previously exposed to phenolic compounds. The SBR1 was inoculated with sludge previously exposed to 2-CP, while the SBR2 was inoculated with sludge previously exposed to p-cresol. An inhibitory effect of 20 mg 2-CP-C/L on both nitrification processes was observed, as specific rates decreased according to a control assay in the absence of 2-CP. However, the inhibitory effect decreased throughout the cycles. At the end of cycle 6, a stable nitrifying process was observed with the sludge previously exposed to 2-CP (SBR1), as an ammonium consumption efficiency and a nitrate production yield close to 99.6 ± 0.3% and 0.99 ± 0.02 were respectively achieved. Despite a complete ammonium consumption being achieved with the sludge previously exposed to p-cresol (SBR2), partial nitrification was observed as nitrate production yield accounted for 0.28 ± 0.08 and nitrite was accumulated within the culture. Nevertheless, both nitrifying sludges had the ability to completely consume 2-CP. The use of SBR systems with nitrifying sludge previously exposed to 2-CP resulted in a better nitrification performance, thus it may be a good alternative for achieving a stable nitrifying respiratory process where complete and simultaneous ammonium and 2-CP consumption can be acquired.
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Affiliation(s)
- Miguel Martínez-Jardines
- Department of Biotechnology CBS, Universidad Autónoma Metropolitana-Iztapalapa , Mexico City , Mexico
| | - Emmanuel Pérez-Alfaro
- Department of Basic Sciences, Universidad Tecnológica del Valle de Chalco , Valle de Chalco , Mexico
| | - R O González-Robles
- Department of Mathematics CBI, Universidad Autónoma Metropolitana-Iztapalapa , Mexico City , Mexico
| | - Anne-Claire Texier
- Department of Biotechnology CBS, Universidad Autónoma Metropolitana-Iztapalapa , Mexico City , Mexico
| | - Flor Cuervo-López
- Department of Biotechnology CBS, Universidad Autónoma Metropolitana-Iztapalapa , Mexico City , Mexico
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Abdel-Tawwab M, Monier MN, Hoseinifar SH, Faggio C. Fish response to hypoxia stress: growth, physiological, and immunological biomarkers. FISH PHYSIOLOGY AND BIOCHEMISTRY 2019; 45:997-1013. [PMID: 30715663 DOI: 10.1007/s10695-019-00614-9] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/22/2019] [Indexed: 05/20/2023]
Abstract
Water quality encompasses the water physical, biological, and chemical parameters. It generally affects the fish growth and welfare. Thus, the success of a commercial aquaculture project depends on supplying the optimum water quality for prompt fish growth at the minimum cost of resources. Although the aquaculture environment is a complicated system, depending on various water quality variables, only less of them have a critical role. One of these vital parameters is dissolved oxygen (DO) level, which requires continuous oversight in aquaculture systems. In addition, the processes of natural stream refinement require suitable DO levels in order to extend for aerobic life forms. The depletion of DO concentration (called hypoxia) in pond water causes great stress on fish where DO levels that remain below 1-2 mg/L for a few hours can adversely affect fish growth resulting in fish death. Furthermore, hypoxia has substantial effects on fish physiological and immune responses, making them more susceptible to diseases. Therefore, to avoid disease outbreak in modern aquaculture production systems where fish are intensified and more crowded, increasing attention should be taken into account on DO levels.
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Affiliation(s)
- Mohsen Abdel-Tawwab
- Department of Fish Biology and Ecology, Central Laboratory for Aquaculture Research, Abbassa, Abo-Hammad, Sharqia, Egypt.
| | - Mohamed N Monier
- Department of Fish Biology and Ecology, Central Laboratory for Aquaculture Research, Abbassa, Abo-Hammad, Sharqia, Egypt
| | - Seyed Hossein Hoseinifar
- Department of Fisheries, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
| | - Caterina Faggio
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy
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Nelson JA, Kraskura K, Lipkey GK. Repeatability of Hypoxia Tolerance of Individual Juvenile Striped Bass Morone saxatilis and Effects of Social Status. Physiol Biochem Zool 2019; 92:396-407. [PMID: 31141466 DOI: 10.1086/704010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Chesapeake Bay is the primary nursery for striped bass (Morone saxatilis), which are increasingly being exposed to hypoxic waters. Tolerance to hypoxia in fish is generally determined by a single exposure of an isolated individual or by exposing large groups of conspecifics to hypoxia without regard to social status. The importance of social context in determining physiological responses to stressors is being increasingly recognized. To determine whether social interactions influence hypoxia tolerance (HT) in striped bass, loss of equilibrium HT was assessed in the same fish while manipulating the social environment around it. Small group settings were used to be more representative of the normal sociality experienced by this species than the paired encounters typically used. After establishing the dominance hierarchy within a group of fish, HT was determined collectively for the individuals in that group, and then new groups were constructed from the same pool of fish. Individuals could then be followed across multiple settings for both repeatability of HT and hierarchy position ( X ¯ = 4.2 ± 0.91 SD groups per individual). HT increased with repeated exposures to hypoxia ( P < 0.001 ), with a significant increase by a third exposure ( P = 0.004 ). Despite this changing HT, rank order of HT was significantly repeatable across trials for 6 mo ( P = 0.012 ). Social status was significantly repeatable across trials of different group composition ( P = 0.02 ) and unrelated to growth rate but affected HT weakly in a complex interaction with size. Final HT was significantly correlated with blood [hemoglobin] and hematocrit. The repeatability and large intraspecific variance of HT in juvenile striped bass suggest that HT is potentially an important determinant of Darwinian fitness in an increasingly hypoxic Chesapeake Bay.
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Dance MA, Rooker JR. Cross-shelf habitat shifts by red snapper (Lutjanus campechanus) in the Gulf of Mexico. PLoS One 2019; 14:e0213506. [PMID: 30870449 PMCID: PMC6417787 DOI: 10.1371/journal.pone.0213506] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 02/22/2019] [Indexed: 11/19/2022] Open
Abstract
Habitat shifts that occur during the life cycles of marine fishes influence population connectivity and structure. A generalized additive modeling approach was used to characterize relationships between environmental variables and the relative abundance of red snapper Lutjanus campechanus over unconsolidated substrate on the continental shelf (<150 m) of the U.S. Gulf of Mexico (GoM) at three different life stages: juvenile (age-0, <125 mm FL), sub-adult (age-1-2, 125-300 mm FL), and adult (age-2+, >300 mm FL). Fisheries independent data (2008-2014) were used to develop separate models for both the eastern and western GoM, and final models were used to predict the relative availability of suitable habitat for each life stage across the two regions. Predictor variables included in final models varied by age class and region, with depth, dissolved oxygen, longitude, and distance to artificial structure common to most models. Depth was among the most influential variables in all models, and preferred depth increased with increasing size/age. Regional differences in fish-habitat relationships were also observed, as relative abundance of larger red snapper over unconsolidated substrates was more closely linked to artificial structure in the eastern GoM. The location of predicted high quality habitat for juvenile red snapper was greatest on the inner Texas shelf and a smaller area east of the Mississippi River Delta, suggesting these two areas may represent important nursery grounds for the respective regions. Clear ontogenetic shifts in the spatial distribution of predicted high quality habitat were evident in both the eastern (expansion from west to east with age) and western (shift from inshore to offshore) GoM. Given the unique population dynamics between the eastern and western GoM, improving our understanding of spatial and temporal variability in habitat quality may be important to maintaining connectivity between juvenile and adult habitats, and may enhance recovery and management of red snapper stocks in the GoM.
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Affiliation(s)
- Michael A. Dance
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Jay R. Rooker
- Department of Marine Biology, Texas A&M University (Galveston Campus), Galveston, Texas, United States of America
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, Texas, United States of America
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Silva-Junior LC, Santos SR, Macedo MC, Nunan GW, Vianna M. Use of a species-rich and highly eutrophic tropical estuary in the South Atlantic by Pleuronectiformes (Teleostei: Acanthopterygii). BIOTA NEOTROPICA 2019. [DOI: 10.1590/1676-0611-bn-2018-0561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract: A total of 1,471 specimens of 16 species of flatfishes (Pleuronectiformes) were caught during 48 sampling campaigns between July 2005 and June 2007 at ten stations in Guanabara Bay, Rio de Janeiro, Brazil. Paralichthyidae was the dominant family, with Etropus crossotus as the dominant species. The outer stations, especially those on the western side of the lower estuary, were distinguished as a result of their higher abundance of flatfishes and number of species. The spatial distribution of E. crossotus and its population structure indicate that this species is an estuarine resident despite the apparent reduction in its area of occupation within the estuarine complex. Among the other species, nine were classified as marine stragglers (Achirus declivis, Bothus ocellatus, Cyclopsetta chittendeni, Etropus longimanus, Paralichthys orbignyanus, P. patagonicus, Syacium micrurum, Symphurus diomedeanus and Trinectes paulistanus) and three as estuarine opportunists (Bothus robinsi, Citharichthys macrops and Syacium papillosum); another three could not be classified due to the small number of captures or lack of previous data (S. tessellatus, A. lineatus and C. spilopterus).
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Modeling Summer Hypoxia Spatial Distribution and Fish Habitat Volume in Artificial Estuarine Waterway. WATER 2018. [DOI: 10.3390/w10111695] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study analyzes the dissolved oxygen (DO) depletion or hypoxia formation affecting the ecological vulnerability of Gyeongin-Ara Waterway (GAW), an artificial estuarine waterway. The physical, chemical, and biochemical factors affecting the summer hypoxia dynamics and distribution are simulated and the habitat volumes of major fish species are calculated. CE-QUAL-W2, a two-dimensional hydrodynamic and water quality model, is applied for the simulation. Comparison with observation reveals that the salinity stratification, vertical DO gradient, and summer hypoxia characteristics are realistically reproduced by the model. Comprehensive analysis of the spatial distributions of the residence time, salinity, and DO concentration reveal that the residence time is longest at the bottom of a freshwater inflow zone. Accordingly, residence time is identified as the physical factor having the greatest influence on hypoxia. It is also clear that a hypoxic water mass diffuses towards the entire waterway during neap tides and summer, when the seawater inflow decreases. Based on the modeling results, the DO depletion drivers are identified and the hypoxic zone formation and distribution are sufficiently explained. Finally, fish habitat volumes are calculated. In particular, the survival habitat volume of Mugil cephalus is found to decrease by 32–34% as a result of hypoxia from July to August. The model employed in this study could be utilized to establish an operational plan for the waterway, which would increase fish habitat volumes.
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Matli VRR, Fang S, Guinness J, Rabalais NN, Craig JK, Obenour DR. Space-Time Geostatistical Assessment of Hypoxia in the Northern Gulf of Mexico. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:12484-12493. [PMID: 30264998 DOI: 10.1021/acs.est.8b03474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nearly every summer, a large hypoxic zone forms in the northern Gulf of Mexico. Research on the causes and consequences of hypoxia requires reliable estimates of hypoxic extent, which can vary at submonthly time scales due to hydro-meteorological variability. Here, we use an innovative space-time geostatistical model and data collected by multiple research organizations to estimate bottom-water dissolved oxygen (BWDO) concentrations and hypoxic area across summers from 1985 to 2016. We find that 27% of variability in BWDO is explained by deterministic trends with location, depth, and date, while correlated stochasticity accounts for 62% of observational variance within a range of 185 km and 28 days. Space-time modeling reduces uncertainty in estimated hypoxic area by 30% when compared to a spatial-only model, and results provide new insights into the temporal variability of hypoxia. For years with shelf-wide cruises in multiple months, hypoxia is most severe in July in 59% of years, 29% in August, and 12% in June. Also, midsummer cruise estimates of hypoxic area are only modestly correlated with summer-wide (June-August) average estimates ( r2 = 0.5), suggesting midsummer cruises are not necessarily reflective of seasonal hypoxic severity. Furthermore, summer-wide estimates are more strongly correlated with nutrient loading than midsummer estimates.
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Affiliation(s)
- V Rohith Reddy Matli
- Department of Civil, Construction & Environmental Engineering , North Carolina State University , Raleigh , North Carolina 27607 , United States
| | - Shiqi Fang
- Department of Civil, Construction & Environmental Engineering , North Carolina State University , Raleigh , North Carolina 27607 , United States
| | - Joseph Guinness
- Department of Statistical Science , Cornell University , Ithaca , New York 14853 , United States
| | - Nancy N Rabalais
- Department of Oceanography and Coastal Sciences , Louisiana State University Baton Rouge , Louisiana 70803 , United States
| | - J Kevin Craig
- NOAA Southeast Fisheries Science Center Beaufort North Carolina 28516 , United States
| | - Daniel R Obenour
- Department of Civil, Construction & Environmental Engineering , North Carolina State University , Raleigh , North Carolina 27607 , United States
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Saari GN, Corrales J, Haddad SP, Chambliss CK, Brooks BW. Influence of Diltiazem on Fathead Minnows Across Dissolved Oxygen Gradients. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2018; 37:2835-2850. [PMID: 30055012 DOI: 10.1002/etc.4242] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 06/24/2018] [Accepted: 07/26/2018] [Indexed: 06/08/2023]
Abstract
Water resources in many arid to semi-arid regions are stressed by population growth and drought. Growing populations and climatic changes are influencing contaminant and water chemistry dynamics in urban inland waters, where flows can be dominated by, or even dependent on, wastewater effluent discharge. In these watersheds, interacting stressors such as dissolved oxygen and environmental contaminants (e.g., pharmaceuticals) have the potential to affect fish physiology and populations. Recent field observations from our group identified the calcium channel blocker (CCB) diltiazem in fish plasma exceeding human therapeutic doses (e.g., Cmin ) in aquatic systems impaired because of nonattainment of dissolved oxygen water quality standards. Therefore our study objectives examined: 1) standard acute and chronic effects of dissolved oxygen and diltiazem to fish, 2) influences of dissolved oxygen at criteria levels deemed protective of aquatic life on diltiazem toxicity to fish, and 3) whether sublethal effects occur at diltiazem water concentrations predicted to cause a human therapeutic level (therapeutic hazard value [THV]) in fish plasma. Dissolved oxygen × diltiazem co-exposures significantly decreased survival at typical stream, lake, and reservoir water quality standards of 5.0 and 3.0 mg dissolved oxygen/L. Dissolved oxygen and diltiazem growth effects were observed at 2 times and 10 times lower than median lethal concentration (LC50) values (1.7 and 28.2 mg/L, respectively). Larval fathead minnow (Pimephales promelas) swimming behavior following low dissolved oxygen and diltiazem exposure generally decreased and was significantly reduced in light-to-dark bursting distance traveled, number of movements, and duration at concentrations as low as the THV. Individual and population level consequences of such responses are not yet understood, particularly in older organisms or other species; however, these findings suggest that assessments with pharmaceuticals and other cardioactive contaminants may underestimate adverse outcomes in fish across dissolved oxygen levels considered protective of aquatic life. Environ Toxicol Chem 2018;37:2835-2850. © 2018 SETAC.
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Affiliation(s)
- Gavin N Saari
- Department of Environmental Science, Baylor University, Waco, Texas, USA
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, Texas, USA
| | - Jone Corrales
- Department of Environmental Science, Baylor University, Waco, Texas, USA
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, Texas, USA
| | - Samuel P Haddad
- Department of Environmental Science, Baylor University, Waco, Texas, USA
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, Texas, USA
| | - C Kevin Chambliss
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, Texas, USA
- Department of Chemistry, Baylor University, Waco, Texas, USA
| | - Bryan W Brooks
- Department of Environmental Science, Baylor University, Waco, Texas, USA
- Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, Texas, USA
- Institute of Biomedical Studies, Baylor University, Waco, Texas, USA
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Du J, Shen J, Park K, Wang YP, Yu X. Worsened physical condition due to climate change contributes to the increasing hypoxia in Chesapeake Bay. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 630:707-717. [PMID: 29494978 DOI: 10.1016/j.scitotenv.2018.02.265] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 02/21/2018] [Accepted: 02/21/2018] [Indexed: 06/08/2023]
Abstract
There are increasing concerns about the impact of worsened physical condition on hypoxia in a variety of coastal systems, especially considering the influence of changing climate. In this study, an EOF analysis of the DO data for 1985-2012, a long-term numerical simulation of vertical exchange, and statistical analysis were applied to understand the underlying mechanisms for the variation of DO condition in Chesapeake Bay. Three types of analysis consistently demonstrated that both biological and physical conditions contribute equally to seasonal and interannual variations of the hypoxic condition in Chesapeake Bay. We found the physical condition (vertical exchange+temperature) determines the spatial and seasonal pattern of the hypoxia in Chesapeake Bay. The EOF analysis showed that the first mode, which was highly related to the physical forcings and correlated with the summer hypoxia volume, can be well explained by seasonal and interannual variations of physical variables and biological activities, while the second mode is significantly correlated with the estuarine circulation and river discharge. The weakened vertical exchange and increased water temperature since the 1980s demonstrated a worsened physical condition over the past few decades. Under changing climate (e.g., warming, accelerated sea-level rise, altered precipitation and wind patterns), Chesapeake Bay is likely to experience a worsened physical condition, which will amplify the negative impact of anthropogenic inputs on eutrophication and consequently require more efforts for nutrient reduction to improve the water quality condition in Chesapeake Bay.
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Affiliation(s)
- Jiabi Du
- Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062, United States; Department of Marine Sciences, Texas A&M University at Galveston, Galveston, TX 77554, United States.
| | - Jian Shen
- Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062, United States
| | - Kyeong Park
- Department of Marine Sciences, Texas A&M University at Galveston, Galveston, TX 77554, United States
| | - Ya Ping Wang
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210093, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China
| | - Xin Yu
- Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062, United States
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Richards CM, van Puffelen JL, Pallud C. Effects of sediment resuspension on the oxidation of acid-volatile sulfides and release of metals (iron, manganese, zinc) in Pescadero estuary (CA, USA). ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2018; 37:993-1006. [PMID: 29168891 DOI: 10.1002/etc.4047] [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: 02/03/2017] [Revised: 04/14/2017] [Accepted: 11/21/2017] [Indexed: 06/07/2023]
Abstract
Bar-built estuaries are unique ecosystems characterized by the presence of a sandbar barrier, which separates the estuary from the ocean for extended periods and can naturally reopen to the ocean with heavy rainfall and freshwater inflows. The physical effects associated with the transition from closed to open state, specifically water mixing and sediment resuspension, often indirectly worsen water quality conditions and are suspected to drive near-annual fish kills at the Pescadero estuary in northern California. The effects of sediment acid-volatile sulfide (AVS) oxidation, specifically oxygen depletion, acidification, and metal release, are believed to aggravate water conditions for fish but remain poorly understood. We performed slurry incubations containing sediment from 4 sites in the Pescadero estuary, representing a gradient from the Pacific Ocean to freshwater tributaries. We measured near-maximum rates of aqueous hydrogen sulfide oxidation, sediment AVS oxidation, sulfate production, and acidification, as well as near-maximum release rates of iron (Fe), manganese (Mn), and zinc (Zn) to the water column. We estimated AVS oxidation rates of 8 to 21 mmol S kg-1 d-1 , which were 3 orders of magnitude higher than aqueous hydrogen sulfide oxidation rates, 6 to 26 μmol S kg-1 d-1 . We suggest that aqueous hydrogen sulfide cannot be responsible for the observed kills because of low concentrations and minimal oxidative effects on pH and metal concentrations. However, the oxidative effects of AVS are potentially severe, decreasing pH to strongly acidic levels and releasing aqueous Fe, Mn, and Zn concentrations up to 11.2 mM, 0.46 mM, and 88 μM, respectively, indicating a potential role in worsening water conditions for fish in the Pescadero estuary. Environ Toxicol Chem 2018;37:993-1006. © 2017 SETAC.
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Affiliation(s)
- Chandra M Richards
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
| | - Jasper L van Puffelen
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
- Sub-Department of Environmental Technology, Wageningen University, Wageningen, The Netherlands
| | - Céline Pallud
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
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Cottrell RS, Fleming A, Fulton EA, Nash KL, Watson RA, Blanchard JL. Considering land-sea interactions and trade-offs for food and biodiversity. GLOBAL CHANGE BIOLOGY 2018; 24:580-596. [PMID: 28833818 DOI: 10.1111/gcb.13873] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 08/14/2017] [Indexed: 05/14/2023]
Abstract
With the human population expected to near 10 billion by 2050, and diets shifting towards greater per-capita consumption of animal protein, meeting future food demands will place ever-growing burdens on natural resources and those dependent on them. Solutions proposed to increase the sustainability of agriculture, aquaculture, and capture fisheries have typically approached development from single sector perspectives. Recent work highlights the importance of recognising links among food sectors, and the challenge cross-sector dependencies create for sustainable food production. Yet without understanding the full suite of interactions between food systems on land and sea, development in one sector may result in unanticipated trade-offs in another. We review the interactions between terrestrial and aquatic food systems. We show that most of the studied land-sea interactions fall into at least one of four categories: ecosystem connectivity, feed interdependencies, livelihood interactions, and climate feedback. Critically, these interactions modify nutrient flows, and the partitioning of natural resource use between land and sea, amid a backdrop of climate variability and change that reaches across all sectors. Addressing counter-productive trade-offs resulting from land-sea links will require simultaneous improvements in food production and consumption efficiency, while creating more sustainable feed products for fish and livestock. Food security research and policy also needs to better integrate aquatic and terrestrial production to anticipate how cross-sector interactions could transmit change across ecosystem and governance boundaries into the future.
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Affiliation(s)
- Richard S Cottrell
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Aysha Fleming
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- CSIRO Land and Water, Hobart, Tasmania, Australia
| | - Elizabeth A Fulton
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
| | - Kirsty L Nash
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Reg A Watson
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Julia L Blanchard
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
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Breitburg D, Levin LA, Oschlies A, Grégoire M, Chavez FP, Conley DJ, Garçon V, Gilbert D, Gutiérrez D, Isensee K, Jacinto GS, Limburg KE, Montes I, Naqvi SWA, Pitcher GC, Rabalais NN, Roman MR, Rose KA, Seibel BA, Telszewski M, Yasuhara M, Zhang J. Declining oxygen in the global ocean and coastal waters. Science 2018; 359:359/6371/eaam7240. [DOI: 10.1126/science.aam7240] [Citation(s) in RCA: 1096] [Impact Index Per Article: 182.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Oxygen is fundamental to life. Not only is it essential for the survival of individual animals, but it regulates global cycles of major nutrients and carbon. The oxygen content of the open ocean and coastal waters has been declining for at least the past half-century, largely because of human activities that have increased global temperatures and nutrients discharged to coastal waters. These changes have accelerated consumption of oxygen by microbial respiration, reduced solubility of oxygen in water, and reduced the rate of oxygen resupply from the atmosphere to the ocean interior, with a wide range of biological and ecological consequences. Further research is needed to understand and predict long-term, global- and regional-scale oxygen changes and their effects on marine and estuarine fisheries and ecosystems.
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Abstract
Internal waves are widespread features of global oceans that play critical roles in mixing and thermohaline circulation. Similarly to surface waves, internal waves can travel long distances, ultimately breaking along continental margins. These breaking waves can transport deep ocean water and associated constituents (nutrients, larvae, and acidic low-oxygen waters) onto the shelf and locally enhance turbulence and mixing, with important effects on nearshore ecosystems. We are only beginning to understand the role internal waves play in shaping nearshore ecosystems. Here, I review the physics of internal waves in shallow waters and identify two commonalities among internal waves in the nearshore: exposure to deep offshore waters and enhanced turbulence and mixing. I relate these phenomena to important ecosystem processes ranging from extreme events to fertilization success to draw general conclusions about the influence of internal waves on ecosystems and the effects of internal waves in a changing climate.
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Affiliation(s)
- C B Woodson
- COBIAlab, College of Engineering, University of Georgia, Athens, Georgia 30602;
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48
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Li G, Liu J, Diao Z, Jiang X, Li J, Ke Z, Shen P, Ren L, Huang L, Tan Y. Subsurface low dissolved oxygen occurred at fresh- and saline-water intersection of the Pearl River estuary during the summer period. MARINE POLLUTION BULLETIN 2018; 126:585-591. [PMID: 28986111 DOI: 10.1016/j.marpolbul.2017.09.061] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 09/26/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
Estuarine oxygen depletion is one of the worldwide problems, which is caused by the freshwater-input-derived severe stratification and high nutrients loading. In this study we presented the horizontal and vertical distributions of dissolved oxygen (DO) in the Pearl River estuary, together with temperature, salinity, chlorophyll a concentration and heterotrophic bacteria abundance obtained from two cruises during the summer (wet) and winter (dry) periods of 2015. In surface water, the DO level in the summer period was lower and varied greater, as compared to the winter period. The DO remained unsaturated in the summer period if salinity is <12 and saturated if salinity is >12; while in the winter period it remained saturated throughout the estuary. In subsurface (>5m) water, the DO level varied from 0.71 to 6.65mgL-1 and from 6.58 to 8.20mgL-1 in the summer and winter periods, respectively. Particularly, we observed an area of ~1500km2 low DO zone in the subsurface water with a threshold of 4mgDOL-1 during this summer period, that located at the fresh- and saline-water intersection where is characterized with severe stratification and high heterotrophic bacteria abundance. In addition, our results indicate that spatial DO variability in surface water was contributed differently by biological and physio-chemical variables in the summer and winter periods, respectively.
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Affiliation(s)
- Gang Li
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
| | - Jiaxing Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Zenghui Diao
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Xin Jiang
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Jiajun Li
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Zhixin Ke
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Pingping Shen
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Lijuan Ren
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Liangmin Huang
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Yehui Tan
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
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Gedan KB, Altieri AH, Feller I, Burrell R, Breitburg D. Community composition in mangrove ponds with pulsed hypoxic and acidified conditions. Ecosphere 2017. [DOI: 10.1002/ecs2.2053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Keryn B. Gedan
- Biological Sciences; George Washington University; 800 22nd Street NW Washington D.C. 20052 USA
| | - Andrew H. Altieri
- Smithsonian Tropical Research Institute; Apartado 0843-03092 Balboa Ancon Panama
| | - Ilka Feller
- Smithsonian Environmental Research Center; 647 Contees Wharf Road Edgewater Maryland 21037 USA
| | - Rebecca Burrell
- Maryland Department of Natural Resources; 580 Taylor Avenue Annapolis Maryland 21401 USA
| | - Denise Breitburg
- Smithsonian Environmental Research Center; 647 Contees Wharf Road Edgewater Maryland 21037 USA
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50
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Lewis NS, DeWitt TH. Effect of Green Macroalgal Blooms on the Behavior, Growth, and Survival of Cockles ( Clinocardium nuttallii) in Pacific NW Estuaries. MARINE ECOLOGY PROGRESS SERIES 2017; 582:105-120. [PMID: 29375170 PMCID: PMC5783308 DOI: 10.3354/meps12328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Nutrient over-enrichment can produce adverse ecological effects within coastal ecosystems and negatively impact the production of ecosystem goods and services. In small estuaries of the U.S. Pacific Northwest, seasonal blooms of green macroalgae (GMA; Family Ulvaceae) are primarily associated with natural nutrient input, rather than anthropogenic sources. This provided us a unique opportunity to investigate the effects of naturally-stimulated macroalgal blooms on intertidal bivalves. Clinocardium nuttallii (heart cockles) are an important species for shellfisheries in the region. In summer population surveys, we found that cockles emerged from the sediment with greater frequency as GMA biomass increased. Experimental manipulation of GMA biomass in the field showed that GMA elicited emergence, evoked above-ground lateral movement, inhibited shell growth, and increased mortality (by 34.0 ± 15.2%) in cockles. Laboratory experiments revealed that the interaction of a weighted barrier at the sediment surface and GMA presence elicited rapid emergence among cockles. Risk assessment of the emergence response in cockles showed that the in situ emergent population experienced 11.0 ± 8.0% mortality due to gull predation, while laboratory exposure to elevated temperatures (≥34 °C) slowed valve-closure, inhibited reburial, and increased mortality, which could have translated to 7.1 ± 1.5% in situ mortality. We found that cockles avoided mortality due to burial below GMA mats by emerging from the sediment, but that behavior consequently put them at risk of mortality due to heat stress or gull predation. Regardless of nutrient source, our research showed that GMA blooms pose a threat to the survival of intertidal bivalves.
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Affiliation(s)
- Nathaniel S. Lewis
- ORISE Research Fellow, Pacific Coastal Ecology Branch, Western Ecology Division, U.S. Environmental Protection Agency, Newport, OR 97365, USA
| | - Theodore H. DeWitt
- Pacific Coastal Ecology Branch, Western Ecology Division, U.S. Environmental Protection Agency, Newport, OR 97365, USA
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