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Waller MJ, Humphries NE, Womersley FC, Loveridge A, Jeffries AL, Watanabe Y, Payne N, Semmens J, Queiroz N, Southall EJ, Sims DW. The vulnerability of sharks, skates, and rays to ocean deoxygenation: Physiological mechanisms, behavioral responses, and ecological impacts. JOURNAL OF FISH BIOLOGY 2024; 105:482-511. [PMID: 38852616 DOI: 10.1111/jfb.15830] [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: 01/30/2024] [Revised: 05/08/2024] [Accepted: 05/20/2024] [Indexed: 06/11/2024]
Abstract
Levels of dissolved oxygen in open ocean and coastal waters are decreasing (ocean deoxygenation), with poorly understood effects on marine megafauna. All of the more than 1000 species of elasmobranchs (sharks, skates, and rays) are obligate water breathers, with a variety of life-history strategies and oxygen requirements. This review demonstrates that although many elasmobranchs typically avoid hypoxic water, they also appear capable of withstanding mild to moderate hypoxia with changes in activity, ventilatory responses, alterations to circulatory and hematological parameters, and morphological alterations to gill structures. However, such strategies may be insufficient to withstand severe, progressive, or prolonged hypoxia or anoxia where anaerobic metabolic pathways may be used for limited periods. As water temperatures increase with climate warming, ectothermic elasmobranchs will exhibit elevated metabolic rates and are likely to be less able to tolerate the effects of even mild hypoxia associated with deoxygenation. As a result, sustained hypoxic conditions in warmer coastal or surface-pelagic waters are likely to lead to shifts in elasmobranch distributions. Mass mortalities of elasmobranchs linked directly to deoxygenation have only rarely been observed but are likely underreported. One key concern is how reductions in habitat volume as a result of expanding hypoxia resulting from deoxygenation will influence interactions between elasmobranchs and industrial fisheries. Catch per unit of effort of threatened pelagic sharks by longline fisheries, for instance, has been shown to be higher above oxygen minimum zones compared to adjacent, normoxic regions, and attributed to vertical habitat compression of sharks overlapping with increased fishing effort. How a compound stressor such as marine heatwaves alters vulnerability to deoxygenation remains an open question. With over a third of elasmobranch species listed as endangered, a priority for conservation and management now lies in understanding and mitigating ocean deoxygenation effects in addition to population declines already occurring from overfishing.
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Affiliation(s)
- Matt J Waller
- Marine Biological Association, The Laboratory, Plymouth, UK
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, UK
| | | | | | | | - Amy L Jeffries
- Marine Biological Association, The Laboratory, Plymouth, UK
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, UK
| | - Yuuki Watanabe
- Research Center for Integrative Evolutionary Science, The Graduate University for Advanced Studies, SOKENDAI, Kanagawa, Japan
| | - Nicholas Payne
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Jayson Semmens
- Institue for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
| | - Nuno Queiroz
- CIBIO/InBIO, Universidade do Porto, Vairão, Portugal
- BIOPOLIS, Program in Genomics, Biodiversity and Land Planning, CIBIO, Vairão, Portugal
| | | | - David W Sims
- Marine Biological Association, The Laboratory, Plymouth, UK
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, UK
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Saavedra LM, Bastías M, Mendoza P, Lagos NA, García-Herrera C, Ponce V, Alvarez F, Llanos-Rivera A. Environmental correlates of oyster farming in an upwelling system: Implication upon growth, biomass production, shell strength and organic composition. MARINE ENVIRONMENTAL RESEARCH 2024; 198:106489. [PMID: 38640688 DOI: 10.1016/j.marenvres.2024.106489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 04/02/2024] [Accepted: 04/03/2024] [Indexed: 04/21/2024]
Abstract
Comprehending the potential effects of environmental variability on bivalves aquaculture becomes crucial for its sustainability under climate change scenarios, specially in the Humboldt Current System (HCS) where upwelling intensification leading to frequent hypoxia and acidification is expected. In a year-long study, Pacific oysters (Magallana gigas) were monitored at two depths (1.5m, 6.5m) in a bay affected by coastal upwelling. Surface waters exhibited warmer, well-oxygenated conditions and higher chlorophyll-a concentrations, while at depth greater hypoxia and acidification events occur, especially during upwelling. Surface cultured oysters exhibited 60 % larger size and 35% greater weight due to faster growth rate during the initial month of cultivation. The condition index (CI) increases in surface oysters after 10 months, whereas those at the bottom maintain a lower index. Food availability, temperature, and oxygen, correlates with higher growth rates, while pH associates with morphometric variables, indicating that larger oysters tend to develop under higher pH. Increased upwelling generally raises CI, but bottom oysters face stressful conditions such as hypoxia and acidification, resulting in lower performance. However, they acclimate by changing the organic composition of their shells and making them stronger. This study suggests that under intensified upwelling scenario, oysters would grow slowly, resulting in smaller sizes and lower performance, but the challenges may be confronted through complex compensation mechanisms among biomass production and maintenance of the shell structure and function. This poses a significant challenge for the sustainability of the aquaculture industry, emphasizing the need for adaptive strategies to mitigate the effects of climate change.
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Affiliation(s)
- Luisa M Saavedra
- Department of Aquatic Systems and EULA Environmental Science Center, Faculty of Environmental Sciences, University of Concepción, Chile.
| | - Manuel Bastías
- Oceanography department, Faculty of Natural and Oceanographic Science, University of Concepción, Chile
| | - Paula Mendoza
- Department of Aquatic Systems and EULA Environmental Science Center, Faculty of Environmental Sciences, University of Concepción, Chile
| | - Nelson A Lagos
- Centro de Investigación e Innovación para el Cambio Climático (CiiCC), Facultad de Ciencias, Universidad Santo Tomás, Santiago, Chile; Instituto Milenio en Socio-Ecología Costera (SECOS), Santiago, Chile
| | - Claudio García-Herrera
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Vania Ponce
- Centro de Investigación e Innovación para el Cambio Climático (CiiCC), Facultad de Ciencias, Universidad Santo Tomás, Santiago, Chile
| | - Fabian Alvarez
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Alejandra Llanos-Rivera
- Oceanography department, Faculty of Natural and Oceanographic Science, University of Concepción, Chile
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Montúfar-Romero M, Valenzuela-Muñoz V, Valenzuela-Miranda D, Gallardo-Escárate C. Hypoxia in the Blue Mussel Mytilus chilensis Induces a Transcriptome Shift Associated with Endoplasmic Reticulum Stress, Metabolism, and Immune Response. Genes (Basel) 2024; 15:658. [PMID: 38927594 PMCID: PMC11203016 DOI: 10.3390/genes15060658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/01/2024] [Accepted: 05/15/2024] [Indexed: 06/28/2024] Open
Abstract
The increase in hypoxia events, a result of climate change in coastal and fjord ecosystems, impacts the health and survival of mussels. These organisms deploy physiological and molecular responses as an adaptive mechanism to maintain cellular homeostasis under environmental stress. However, the specific effects of hypoxia on mussels of socioeconomic interest, such as Mytilus chilensis, are unknown. Using RNA-seq, we investigated the transcriptomic profiles of the gills, digestive gland, and adductor muscle of M. chilensis under hypoxia (10 days at 2 mg L-1) and reoxygenation (10 days at 6 mg L-1). There were 15,056 differentially expressed transcripts identified in gills, 11,864 in the digestive gland, and 9862 in the adductor muscle. The response varied among tissues, showing chromosomal changes in Chr1, Chr9, and Chr10 during hypoxia. Hypoxia regulated signaling genes in the Toll-like, mTOR, citrate cycle, and apoptosis pathways in gills, indicating metabolic and immunological alterations. These changes suggest that hypoxia induced a metabolic shift in mussels, reducing reliance on aerobic respiration and increasing reliance on anaerobic metabolism. Furthermore, hypoxia appeared to suppress the immune response, potentially increasing disease susceptibility, with negative implications for the mussel culture industry and natural bed populations. This study provides pivotal insights into metabolic and immunological adaptations to hypoxia in M. chilensis, offering candidate genes for adaptive traits.
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Affiliation(s)
- Milton Montúfar-Romero
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, P.O. Box 160-C, Concepción 4030000, Chile; (M.M.-R.); (V.V.-M.); (D.V.-M.)
- Biotecnology Center, Universidad de Concepción, Concepción 4030000, Chile
- Instituto Público de Investigación de Acuicultura y Pesca (IPIAP), Guayaquil 090314, Ecuador
| | - Valentina Valenzuela-Muñoz
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, P.O. Box 160-C, Concepción 4030000, Chile; (M.M.-R.); (V.V.-M.); (D.V.-M.)
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Naturaleza, Universidad San Sebastián, Concepción 4030000, Chile
| | - Diego Valenzuela-Miranda
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, P.O. Box 160-C, Concepción 4030000, Chile; (M.M.-R.); (V.V.-M.); (D.V.-M.)
- Biotecnology Center, Universidad de Concepción, Concepción 4030000, Chile
| | - Cristian Gallardo-Escárate
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, P.O. Box 160-C, Concepción 4030000, Chile; (M.M.-R.); (V.V.-M.); (D.V.-M.)
- Biotecnology Center, Universidad de Concepción, Concepción 4030000, Chile
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Paredes-Molina FJ, Chaparro OR, Navarro JM, Cubillos VM, Paschke K, Márquez F, Averbuj A, Zabala MS, Bökenhans V, Pechenik JA. Upwelling as a stressor event during embryonic development: Consequences for encapsulated and early juvenile stages of the marine gastropod Acanthina monodon. MARINE ENVIRONMENTAL RESEARCH 2024; 193:106270. [PMID: 38011827 DOI: 10.1016/j.marenvres.2023.106270] [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: 05/31/2023] [Revised: 10/18/2023] [Accepted: 11/10/2023] [Indexed: 11/29/2023]
Abstract
Upwelling phenomena alter the physical and chemical parameters of the sea's subsurface waters, producing low levels of temperature, pH and dissolved oxygen, which can seriously impact the early developmental stages of marine organisms. To understand how upwelling can affect the encapsulated development of the gastropod Acanthina monodon, capsules containing embryos at different stages of development (initial, intermediate and advanced) were exposed to upwelling conditions (pH = 7.6; O2 = 3 mg L-1; T° = 9 °C) for a period of 7 days. Effects of treatment were determined by estimating parameters such as time to hatching, number of hatchlings per capsule, percentage of individuals with incomplete development, and shell parameters such as shell shape and size, shell strength, and the percentage of the organic/inorganic content. We found no significant impacts on hatching time, number of hatchlings per capsule, or percentage of incomplete development in either the presence or absence of upwelling, regardless of developmental stage. On the other hand, latent effects on encapsulated stages of A. monodon were detected in embryos that had been exposed to upwelling stress in the initial embryonic stage. The juveniles from this treatment hatched at smaller sizes and with higher organic content in their shells, resulting in a higher resistance to cracking 30 days after hatching, due to greater elasticity. Geometric morphometric analysis showed that exposure to upwelling condition induced a change in the morphology of shell growth in all post-hatching juveniles (0-30 days), regardless of embryonic developmental stage at the time of exposure. Thus, more elongated shells (siphonal canal and posterior region) and more globular shells were observed in newly hatched juveniles that had been exposed to the upwelling condition. The neutral or even positive upwelling exposure results suggests that exposure to upwelling events during the encapsulated embryonic phase of A. monodon development might not have major impacts on the future juvenile stages. However, this should be taken with caution in consideration of the increased frequency and intensity of upwelling events predicted for the coming decades.
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Affiliation(s)
- F J Paredes-Molina
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile.
| | - O R Chaparro
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - J M Navarro
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile; Centro FONDAP de Investigación de Ecosistemas Marinos de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile
| | - V M Cubillos
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - K Paschke
- Instituto de Acuicultura, Universidad Austral de Chile, Puerto Montt, Chile; Centro FONDAP de Investigación de Ecosistemas Marinos de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile; Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems, BASE, Universidad Austral de Chile, Chile
| | - F Márquez
- Laboratorio de Reproducción y Biología Integrativa de Invertebrados Marinos (LARBIM)-IBIOMAR, CCT, CONICET-CENPAT, Puerto Madryn, Chubut, Argentina; Universidad Nacional de La Patagonia San Juan Bosco (UNPSJB), Puerto Madryn, Argentina
| | - A Averbuj
- Laboratorio de Reproducción y Biología Integrativa de Invertebrados Marinos (LARBIM)-IBIOMAR, CCT, CONICET-CENPAT, Puerto Madryn, Chubut, Argentina
| | - M S Zabala
- Laboratorio de Reproducción y Biología Integrativa de Invertebrados Marinos (LARBIM)-IBIOMAR, CCT, CONICET-CENPAT, Puerto Madryn, Chubut, Argentina
| | - V Bökenhans
- Laboratorio de Reproducción y Biología Integrativa de Invertebrados Marinos (LARBIM)-IBIOMAR, CCT, CONICET-CENPAT, Puerto Madryn, Chubut, Argentina
| | - J A Pechenik
- Biology Department, Tufts University, Medford, MA, 02155, USA
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Vásquez C, Vera-Escalona I, Brante A, Silva F, Hernández-Miranda E. Natural mega disturbances drive spatial and temporal changes in diversity and genetic structure on the toadfish Aphos porosus. Sci Rep 2023; 13:13902. [PMID: 37626080 PMCID: PMC10457337 DOI: 10.1038/s41598-023-40698-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 08/16/2023] [Indexed: 08/27/2023] Open
Abstract
Natural disturbances can modify extinction-colonization dynamics, driving changes in the genetic diversity and structure of marine populations. Along Chilean coast (36°S, 73°W), a strong hypoxic-upwelling event in 2008, and a mega earthquake-tsunami in 2010 caused mass mortality within the Aphos porosus population, which is a vulnerable species with low dispersal potential. We evaluated the effects of these two major disturbances on the diversity and spatial-temporal genetic structure of Aphos porosus in two neighboring areas that were impacted on different levels (High level: Coliumo Bay; Low level: Itata Shelf). Thirteen microsatellites (from 2008 to 2015) amplified in individuals collected from both locations were used to evaluate the effects of the two disturbances. Results showed that after the strong hypoxic-upwelling event and the mega earthquake-tsunami, Aphos porosus populations exhibited lower genetic diversity and less effective population sizes (Ne < 20), as well as asymmetries in migration and spatial-temporal genetic structure. These findings suggest a rise in extinction-recolonization dynamics in local Aphos porosus populations after the disturbances, which led to a loss of local genetic diversity (mainly in Coliumo Bay area impacted the most), and to greater spatial-temporal genetic structure caused by drift and gene flow. Our results suggest that continuous genetic monitoring is needed in order to assess potential risks for Aphos porosus in light of new natural and anthropogenic disturbances.
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Affiliation(s)
- Cynthia Vásquez
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, Concepción, Chile
- Programa de Doctorado en Sistemática y Biodiversidad, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Iván Vera-Escalona
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Antonio Brante
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
- Center for Research on Biodiversity and Sustainable Environments (CIBAS), Universidad Católica de la Santísima Concepción, Concepción, Chile
- Programa de Doctorado en Ciencias Mención en Biodiversidad y Biorecursos, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Francisco Silva
- Programa de Doctorado en Ciencias Mención en Biodiversidad y Biorecursos, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Eduardo Hernández-Miranda
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, Concepción, Chile.
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile.
- Laboratorio de Investigación en Ecosistemas Acuáticos (LInEA), Concepción, Chile.
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Alarcón-Vivero M, Moena NRT, Gonzalez F, Jopia-Contreras P, Aspé E, Briones HU, Fernandez KS. Anaerobic biofilm enriched with an ammonia tolerant methanogenic consortium to improve wastewater treatment in the fishing industry. Biotechnol Lett 2022; 44:239-251. [PMID: 35037233 DOI: 10.1007/s10529-021-03213-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 11/29/2021] [Indexed: 11/29/2022]
Abstract
The digestion efficiency of liquid industrial wastes increases when using bioreactors colonized by microbial biofilms. High concentrations of proteins derived from the fish processing industry lead to the production of ammonia, which inhibits methane production. Two bioreactors were constructed to compare methanogenic activity: one enriched with mMPA (methylaminotrofic methane production archaea) consortia (control bioreactor), and the second with NH3 tolerant consortia (treatment bioreactor). Ammonia tolerant activity was assessed by applying an ammonia shock (755 mg NH3/L). Methane production, consumption of total organic carbon (TOC) and the taxonomic composition of bacteria and archaea was evaluated using 16S rDNA in the acclimatization, ammonia shock, and recovery phases.The ammonia shock significantly affected both methane production and the consumption of TOC in the control reactor (p < 0.05) and taxonomical composition of the microbial consortia (OTU). These values remained constant in the treatment reactor. The analysis of biofilm composition showed a predominance of Methanosarcinaceae (Methanomethylovorans sp., and probably two different species of Methanosarcina sp.) in bioreactors. These results demonstrate that using acclimated biofilms enriched with ammonia tolerant methanogens control the inhibitory effect of ammonia on methanogenesis.
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Affiliation(s)
- Manuel Alarcón-Vivero
- Instituto de Acuicultura, Universidad Austral de Chile (UACh), Sede Puerto Montt, Puerto Montt, Chile
| | - Nathaly Ruiz-Tagle Moena
- Lab. Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile
| | - Fidelina Gonzalez
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | | | - Estrella Aspé
- Departamento de Ingeniería Química, Facultad de Ingeniería, Universidad de Concepción, Concepción, Chile
| | - Homero Urrutia Briones
- Lab. Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile.,Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Katherine Sossa Fernandez
- Lab. Biopelículas y Microbiología Ambiental, Centro de Biotecnología, Universidad de Concepción, Concepción, Chile. .,Facultad de Ciencias Forestales, Universidad de Concepción, Concepción, Chile.
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Seguel V, Guzmán F, Bascur M, Riera R, Urzúa Á. Temporal variation in larval biochemical condition at hatching of the red squat lobster Pleuroncodes monodon(Decapoda: Munididae) from Humboldt Current System. INVERTEBR REPROD DEV 2019. [DOI: 10.1080/07924259.2019.1647471] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Victoria Seguel
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Fabián Guzmán
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
- Centro de Investigación en Biodiversidad y Ambientes Sustentables (CIBAS), Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Miguel Bascur
- Programa de Magíster en Ecología Marina, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Rodrigo Riera
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Ángel Urzúa
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
- Centro de Investigación en Biodiversidad y Ambientes Sustentables (CIBAS), Universidad Católica de la Santísima Concepción, Concepción, Chile
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Krautz MC, Hernández-Miranda E, Veas R, Bocaz P, Riquelme P, Quiñones RA. An estimate of the percentage of non-predatory dead variability in coastal zooplankton of the southern Humboldt Current System. MARINE ENVIRONMENTAL RESEARCH 2017; 132:103-116. [PMID: 29126632 DOI: 10.1016/j.marenvres.2017.10.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 06/16/2017] [Accepted: 10/17/2017] [Indexed: 06/07/2023]
Abstract
Non-predatory dead variability in zooplankton remains poorly quantified worldwide. Here, we make the first estimation of the percentage of dead organisms in coastal zooplankton communities in the Humboldt Current System (HCS) under in situ conditions. The study was conducted in four coastal sites of the southern HCS (between 36 and 37°S) over a period of one year. Percentages of dead organisms were based on the classification as live or dead of 158,220 holoplankton and 17,591 meroplankton individuals using neutral red staining technique. The percentage of dead organisms in total-zooplankton was between 4.3% in Coronel Bay (summer) and 76.9% in Llico (autumn). The percentage of dead total-holoplankton varied from 4.2% (Itata River Mouth; autumn) to 77.6% (Llico; autumn), while the percentage of dead total-meroplankton ranged from 1.5% to 56.8% in Coronel Bay and Coliumo Bay, respectively. The most abundant taxa analyzed were the copepods Acartia sp., Paracalanus sp., Calanoides sp., Cladocera, Polychaeta, and the eggs of anchoveta Engraulis ringens. Among these taxa, there was a high degree of interspecific variability in the estimation of the dead organisms. The Pearson correlation shows significant relationships between maximum temperature, and minimum salinity, with the percentage of dead individuals of Acartia sp. and Paracalanus sp. Environmental factors explaining those relationships were: the El Niño 2015-2016 event, and freshwater river runoff. The use of vital staining to estimate non-predatory death for total-zooplankton and selected sentinel species is a promising tool to establish baselines to evaluate natural perturbations (e.g. ENSO), and anthropogenic alterations in coastal pelagic ecosystems.
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Affiliation(s)
- M C Krautz
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Laboratorio de Investigación en Ecosistemas Acuáticos (LInEA), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - E Hernández-Miranda
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Laboratorio de Investigación en Ecosistemas Acuáticos (LInEA), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, O'Higgins 1695, Concepción, Chile.
| | - R Veas
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Laboratorio de Investigación en Ecosistemas Acuáticos (LInEA), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - P Bocaz
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Laboratorio de Investigación en Ecosistemas Acuáticos (LInEA), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - P Riquelme
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Laboratorio de Investigación en Ecosistemas Acuáticos (LInEA), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - R A Quiñones
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Laboratorio de Investigación en Ecosistemas Acuáticos (LInEA), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, O'Higgins 1695, Concepción, Chile
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9
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Hernández-Miranda E, Veas R, Anabalón V, Quiñones RA. Short-term alteration of biotic and abiotic components of the pelagic system in a shallow bay produced by a strong natural hypoxia event. PLoS One 2017; 12:e0179023. [PMID: 28715447 PMCID: PMC5513412 DOI: 10.1371/journal.pone.0179023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 05/23/2017] [Indexed: 11/21/2022] Open
Abstract
In January 2008 there was an intensive and extensive upwelling event in the southern Humboldt Current System. This event produced an intrusion of water with low dissolved oxygen into Coliumo Bay, which caused massive mortality and the beaching of pelagic and benthic organisms, including zooplankton. During this event, which lasted 3 to 5 days, we studied and evaluated the effect of the hypoxic water in the bay on the abundance of macrozooplankton, nanoplankton and microphytoplankton, the concentration of several nutrients and hydrographic conditions. At the beginning of the hypoxia event the water column had very low dissolved oxygen concentrations (<0.5 mL O2 L-1), low temperatures and high salinity which are characteristics of the oxygen minimum zone from the Humboldt Current System. Redox, pH, nitrate, phosphate, silicate and chlorophyll-a values were the lowest, while nitrate and the phaeopigment values were the highest. The N:P ratio was below 16, and the abundance of nano- and microphytoplankton were at their lowest, the latter also with the lowest proportion of live organisms. Macrozooplankton had the greatest abundance during hypoxia, dominated mainly by crustacean, fish eggs and amphipods. The hypoxia event generated a strong short-term alteration of all biotic and abiotic components of the pelagic system in Coliumo Bay and the neighboring coastal zone. These negative effects associated with strong natural hypoxia events could have important consequences for the productivity and ecosystem functioning of the coastal zone of the Humboldt Current System if, as suggested by several models, winds favorable to upwelling should increase due to climate change. The effects of natural hypoxia in this coastal zone can be dramatic especially for pelagic and benthic species not adapted to endure conditions of low dissolved oxygen.
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Affiliation(s)
- Eduardo Hernández-Miranda
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Casilla 160-C, Universidad de Concepción, Concepción, Chile
| | - Rodrigo Veas
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Valeria Anabalón
- Department of Oceanography, Casilla 160-C, Universidad de Concepción, Concepción, Chile
| | - Renato A. Quiñones
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Casilla 160-C, Universidad de Concepción, Concepción, Chile
- Department of Oceanography, Casilla 160-C, Universidad de Concepción, Concepción, Chile
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Tasaki J, Nakayama K, Shimizu I, Yamada H, Suzuki T, Nishiyama N, Yamane M. Cellular and molecular hypoxic response in common carp (Cyprinus carpio) exposed to linear alkylbenzene sulfonate at sublethal concentrations. ENVIRONMENTAL TOXICOLOGY 2017; 32:122-130. [PMID: 26589110 DOI: 10.1002/tox.22217] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/21/2015] [Accepted: 11/01/2015] [Indexed: 06/05/2023]
Abstract
Linear alkylbenzene sulfonate (LAS) is an anionic surfactant commonly used in cleaning agents such as laundry detergents. Trace amounts of LAS are released into environmental waters after processing in wastewater treatment plants after the use of this chemical. Acute toxicity of LAS has been well-studied using various organisms, and its effects are particularly well known in fish. LAS damages fish gill morphology and induces mucous excretion from these organs. LAS also causes hematological changes. These observations suggest that LAS might induce hypoxic conditions in fish. However, the connections between hypoxia and hematological changes at the cellular and molecular levels remain unknown. Common carp were exposed to LAS at concentrations of 625, 1250, and 2500 μg/L for 96 h. A total of 9-10 fish were sampled at the end of the exposure period for each concentration. For hematological analysis, carp blood was sampled from the caudal vein. Gill tissue was used for real-time PCR analysis to evaluate transcriptional changes of hypoxia-induced genes. The number of normal red blood cells and the number of immature red blood cells were significantly decreased and increased, respectively, in fish exposed to 2500 µg/L LAS. The hypoxic marker genes hypoxia inducible factor 1α, myoglobin 1, and erythropoietin 2 were upregulated in these fish. Our results suggest that LAS decreases erythrocyte numbers and induces hypoxic conditions. In addition, LAS-exposed fish increase production of immature erythrocytes and upregulate myoglobin expression in gills to improve oxygen transport and absorption. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 122-130, 2017.
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Affiliation(s)
- Junichi Tasaki
- R&D Core Technology Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi, 321-3497, Japan
| | - Kei Nakayama
- Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-Cho, Matsuyama, 790-8577, Japan
| | - Ichiyo Shimizu
- Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-Cho, Matsuyama, 790-8577, Japan
| | - Hiroko Yamada
- WDB Corporation, Yusen Building 2F, 2-3-2 Marunouchi, Chiyoda-Ku, Tokyo, 100-0005, Japan
| | - Takahiro Suzuki
- R&D Core Technology Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi, 321-3497, Japan
| | - Naohiro Nishiyama
- R&D Core Technology Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi, 321-3497, Japan
| | - Masayuki Yamane
- R&D Core Technology Safety Science Research, Kao Corporation, 2606 Akabane, Ichikai-Machi, Haga-Gun, Tochigi, 321-3497, Japan
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11
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Labra FA, Hernández-Miranda E, Quiñones RA. Dynamic relationships between body size, species richness, abundance, and energy use in a shallow marine epibenthic faunal community. Ecol Evol 2015; 5:391-408. [PMID: 25691966 PMCID: PMC4314271 DOI: 10.1002/ece3.1343] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 11/05/2014] [Accepted: 11/07/2014] [Indexed: 11/28/2022] Open
Abstract
We study the temporal variation in the empirical relationships among body size (S), species richness (R), and abundance (A) in a shallow marine epibenthic faunal community in Coliumo Bay, Chile. We also extend previous analyses by calculating individual energy use (E) and test whether its bivariate and trivariate relationships with S and R are in agreement with expectations derived from the energetic equivalence rule. Carnivorous and scavenger species representing over 95% of sample abundance and biomass were studied. For each individual, body size (g) was measured and E was estimated following published allometric relationships. Data for each sample were tabulated into exponential body size bins, comparing species-averaged values with individual-based estimates which allow species to potentially occupy multiple size classes. For individual-based data, both the number of individuals and species across body size classes are fit by a Weibull function rather than by a power law scaling. Species richness is also a power law of the number of individuals. Energy use shows a piecewise scaling relationship with body size, with energetic equivalence holding true only for size classes above the modal abundance class. Species-based data showed either weak linear or no significant patterns, likely due to the decrease in the number of data points across body size classes. Hence, for individual-based size spectra, the SRA relationship seems to be general despite seasonal forcing and strong disturbances in Coliumo Bay. The unimodal abundance distribution results in a piecewise energy scaling relationship, with small individuals showing a positive scaling and large individuals showing energetic equivalence. Hence, strict energetic equivalence should not be expected for unimodal abundance distributions. On the other hand, while species-based data do not show unimodal SRA relationships, energy use across body size classes did not show significant trends, supporting energetic equivalence.
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Affiliation(s)
- Fabio A Labra
- Centro de Investigación e Innovación para el Cambio Climático, Facultad de Ciencias, Universidad Santo TomasEjercito 146, Código Postal, 8370003, Santiago, Chile
| | - Eduardo Hernández-Miranda
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales & Oceanográficas, Universidad de ConcepciónConcepción, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Casilla 160-C, Universidad de ConcepciónConcepción, Chile
| | - Renato A Quiñones
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Ciencias Naturales & Oceanográficas, Universidad de ConcepciónConcepción, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Casilla 160-C, Universidad de ConcepciónConcepción, Chile
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12
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Veas R, Hernández-Miranda E, Quiñones RA, Díaz-Cabrera E, Rojas JM, Fariña JM. The influence of environmental factors on the abundance and recruitment of the sand crab Emerita analoga (Stimpson 1857): source-sink dynamics? MARINE ENVIRONMENTAL RESEARCH 2013; 89:9-20. [PMID: 23688579 DOI: 10.1016/j.marenvres.2013.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 04/08/2013] [Accepted: 04/18/2013] [Indexed: 05/26/2023]
Abstract
The sandcrab Emerita analoga is the dominant species inhabiting sandy beaches along the Pacific coast of the American continent. In our study, 10 sandy beaches were sampled seasonally from 2006 to 2011, including coastal planktonic sampling from 2006 to 2008. Two major population cores were detected, the first one in the northern part of the study area and the second in the area immediately to the south of the Itata River mouth. Zoeal stages were found along the entire coastal zone. Highest densities and recruitment were found during spring and summer of each year. PLS regression indicated that source-sink habitat proxies correlated positively with morphodynamic parameters; while beach slope and total organic matter were negatively correlated. These results agree with the source-sink hypothesis, finding higher densities of adults, recruits and cohort recurrence on open coast beaches with milder physical dynamics. Furthermore, a hypoxic event and a mega-earthquake/tsunami negatively affected recruitment at the inter-annual scale.
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Affiliation(s)
- R Veas
- Programa de Postgrados en Oceanografía, Departamento de Oceanografía, Casilla 160-C, Universidad de Concepción, Concepción, Chile
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Hernández-Miranda E, Veas R, Labra FA, Salamanca M, Quiñones RA. Response of the epibenthic macrofaunal community to a strong upwelling-driven hypoxic event in a shallow bay of the southern Humboldt Current System. MARINE ENVIRONMENTAL RESEARCH 2012; 79:16-28. [PMID: 22626877 DOI: 10.1016/j.marenvres.2012.04.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 04/19/2012] [Accepted: 04/20/2012] [Indexed: 06/01/2023]
Abstract
In January 2008, most of the southern coastal zone of the Humboldt Current System was affected by an intense upwelling event. This caused an intrusion of equatorial sub-surface water into the coastal zone, generating severe hypoxic conditions (≤0.5 ml O(2) l(-1)) three days after the beginning of the event. A rapid, massive die-off of marine organisms occurred in Coliumo Bay on January 3rd, affecting zooplankton, mollusks, crustaceans and fishes. Normal oxygen concentrations were observed on January 10th, seven days after the hypoxic event. Here we analyze the response of the epibenthic macrofauna community using data spanning three years of sampling which encompass the short-term hypoxic disturbance in the bay. We found that (i) strong changes in total density, total biomass, and diversity occurred immediately after the hypoxic event, negatively affecting crustaceans and fishes, while gastropods were favored, (ii) initial changes were reverted over a period of three months, (iii) on an inter-annual time scale, species richness and diversity decreased following the hypoxic event. Total density increased strongly, but total biomass showed no clear inter-annual trend. These results show that, while initial recovery from hypoxia was fast, over longer time scales the community exhibited a shift to an alternative structure dominated principally by Nassariid scavenger species.
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Affiliation(s)
- Eduardo Hernández-Miranda
- Programa de Investigación Marina de Excelencia (PIMEX), Facultad de Cs. Naturales & Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile.
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14
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Veas R, Hernández-Miranda E, Quiñones RA, Carrasco FD. Spatio-temporal biodiversity of soft bottom macrofaunal assemblages in shallow coastal waters exposed to episodic hypoxic events. MARINE ENVIRONMENTAL RESEARCH 2012; 78:1-14. [PMID: 22521572 DOI: 10.1016/j.marenvres.2012.02.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 02/26/2012] [Accepted: 02/27/2012] [Indexed: 05/31/2023]
Abstract
The Humboldt Current System (HCS) has one of the three most important oxygen minimum zones (OMZ) of the global ocean. Several studies have looked at the macrofaunal benthic assemblages inhabiting the continental shelf and shallow bays off central-southern Chile associated with low oxygen areas, but little is known about open coast macrofaunal communities within this zone, which are frequently subjected to the low oxygen conditions of Equatorial Subsurface Waters (ESSW). In order to assess local and mesoscale coastal macrofauna dynamics, the sampling area (ca. 40 linear km) was divided into seven local zones (Cobquecura, southern Cobquecura, northern Itata, Itata River mouth, external, southern Itata, and Coliumo). Eight oceanographic cruises were carried out between May 2006 and February 2008 covering 16 coastal sampling sites, between 36°07'S and 36°30'S. The macrofaunal assemblage was dominated by polychaetes, crustaceans, and mollusks. Our results suggest a high degree of temporal faunal stability on the mesoscale in soft bottom communities along the open coast, given the persistence of a faunal assemblage dominated by organisms tolerant of low oxygen conditions. While there is some local variability in community attributes, the main structuring factor for soft bottom communities in the shallow coastal area off central-southern Chile is the seasonal intrusion of low oxygen ESSW.
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Affiliation(s)
- Rodrigo Veas
- Programa de Doctorado en Oceanografía, Departamento de Oceanografía, Casilla 160-C, Universidad de Concepción, Concepción, Chile
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