Primary Life Stage Boron Isotope and Trace Elements Incorporation in Aposymbiotic Acropora millepora Coral under Ocean Acidification and Warming

The results of the study of macro- (Ca, Mg) and micro- (Mn, Zn, Cu, Fe) elements content in the pectoral fin tissue of adult sockeye salmon Oncorhynchus nerka from the rivers Bolshaya and Kamchatka as well as from Azabachye Lake (Kamchatka Peninsula) are presented. The significant differences in the contents in samples from the three waterbodies were found. It was ascertained that the largest ash proportion (and the mass fraction of trace elements) in dry matter contained in the tissues of sockeye salmon from Kamchatka River, the smallest in the sample of Azabachye Lake. The Ca content was 98 % of the ash mass in all samples; Mg accounted for slightly less than 2 %. The proportion of the remaining elements varied within 0.1 %, and exactly in this range the differences in the microelement composition between the samples were revealed. In sockeye salmon tissues from the Kamchatka River, the content of heavy metals as well as Ca and Mg was higher than in other samples, and their percentage ratio considerably differed from the others. Obviously, the water bodies studied sufficiently distinguish in hydrochemical indices, and that is the cause of differences in bioaccumulation intensities of trace elements in fish tissues at the freshwater life stage.

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Modelling ocean acidification effects with life stage-specific responses alters spatiotemporal patterns of catch and revenues of American lobster, Homarus americanus

Scientific Reports ◽

10.1038/s41598-021-02253-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Travis C. Tai ◽

Piero Calosi ◽

Helen J. Gurney-Smith ◽

William W. L. Cheung

Keyword(s):

Climate Change ◽

Ocean Acidification ◽

Large Scale ◽

Life Stage ◽

Homarus Americanus ◽

Minimum Size ◽

Future Climate Change ◽

American Lobster ◽

Fishing Pressure ◽

Size Limits

AbstractOcean acidification (OA) affects marine organisms through various physiological and biological processes, yet our understanding of how these translate to large-scale population effects remains limited. Here, we integrated laboratory-based experimental results on the life history and physiological responses to OA of the American lobster, Homarus americanus, into a dynamic bioclimatic envelope model to project future climate change effects on species distribution, abundance, and fisheries catch potential. Ocean acidification effects on juvenile stages had the largest stage-specific impacts on the population, while cumulative effects across life stages significantly exerted the greatest impacts, albeit quite minimal. Reducing fishing pressure leads to overall increases in population abundance while setting minimum size limits also results in more higher-priced market-sized lobsters (> 1 lb), and could help mitigate the negative impacts of OA and concurrent stressors (warming, deoxygenation). However, the magnitude of increased effects of climate change overweighs any moderate population gains made by changes in fishing pressure and size limits, reinforcing that reducing greenhouse gas emissions is most pressing and that climate-adaptive fisheries management is necessary as a secondary role to ensure population resiliency. We suggest possible strategies to mitigate impacts by preserving important population demographics.

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Effects of CO<sub>2</sub>-driven ocean acidification on early life stages of marine medaka (<i>Oryzias melastigma</i>)

Biogeosciences Discussions ◽

10.5194/bgd-12-1-2015 ◽

2015 ◽

Vol 12 (1) ◽

pp. 1-20 ◽

Cited By ~ 3

Author(s):

J. Mu ◽

F. Jin ◽

J. Wang ◽

N. Zheng ◽

Y. Cong

Keyword(s):

Ocean Acidification ◽

Elevated Co2 ◽

Early Life ◽

Life Stage ◽

Control Group ◽

Hatching Rate ◽

Marine Medaka ◽

Saturation State ◽

Oryzias Melastigma ◽

Co2 Level

Abstract. The potential effects of elevated CO2 level and reduced carbonate saturation state in marine environment on fishes and other non-calcified organisms are still poorly known. In present study, we investigated the effects of ocean acidification on embryogenesis and organogenesis of newly hatched larvae of marine medaka (Oryzias melastigma) after 21 d exposure of eggs to different artificially acidified seawater (pH 7.6 and 7.2, respectively), and compared with those in control group (pH 8.2). Results showed that CO2-driven seawater acidification (pH 7.6 and 7.2) had no detectable effect on hatching time, hatching rate, and heart rate of embryos. However, the deformity rate of larvae in pH 7.2 treatment was significantly higher than that in control treatment. The left and right sagitta areas did not differ significantly from each other in each treatment. However, the mean sagitta area of larvae in pH 7.6 treatment was significantly smaller than that in the control (p = 0.024). These results suggest that although marine medaka might be more tolerant of elevated CO2 than some other fishes, the effect of elevated CO2 level on the calcification of otolith is likely to be the most susceptibly physiological process of pH regulation in early life stage of marine medaka.

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Effects of Ocean Acidification on Molting, Oxidative Stress, and Gut Microbiota in Juvenile Horseshoe Crab Tachypleus tridentatus

Frontiers in Physiology ◽

10.3389/fphys.2021.813582 ◽

2022 ◽

Vol 12 ◽

Author(s):

Ximei Liu ◽

Jiani Liu ◽

Kai Xiong ◽

Caoqi Zhang ◽

James Kar-Hei Fang ◽

...

Keyword(s):

Oxidative Stress ◽

Gut Microbiota ◽

Ocean Acidification ◽

Horseshoe Crab ◽

Life Stage ◽

Growth Index ◽

Immune Defense ◽

Control Group ◽

Tachypleus Tridentatus ◽

Horseshoe Crabs

Anthropogenic elevation of atmospheric carbon dioxide (CO2) drives global-scale ocean acidification (OA), which has aroused widespread concern for marine ecosystem health. The tri-spine horseshoe crab (HSC) Tachypleus tridentatus has been facing the threat of population depletion for decades, and the effects of OA on the physiology and microbiology of its early life stage are unclear. In this study, the 1st instar HSC larvae were exposed to acidified seawater (pH 7.3, pH 8.1 as control) for 28 days to determine the effects of OA on their growth, molting, oxidative stress, and gut microbiota. Results showed that there were no significant differences in growth index and molting rate between OA group and control group, but the chitinase activity, β-NAGase activity, and ecdysone content in OA group were significantly lower than those of the control group. Compared to the control group, reactive oxygen species (ROS) and malondialdehyde (MDA) contents in OA group were significantly increased at the end of the experiment. Superoxide dismutase (SOD), catalase (CAT), and alkaline phosphatase (AKP) activities increased first and then decreased, glutathione peroxidase (GPX) decreased first and then increased, and GST activity changed little during the experiment. According to the result of 16S rRNA sequencing of gut microbiota, microbial-mediated functions predicted by PICRUSt showed that “Hematopoietic cell lineage,” “Endocytosis,” “Staphylococcus aureus infection,” and “Shigellosis” pathways significantly increased in OA group. The above results indicate that OA had no significant effect on growth index and molting rate but interfered with the activity of chitinolytic enzymes and ecdysone expression of juvenile horseshoe crabs, and caused oxidative stress. In addition, OA had adverse effects on the immune defense function and intestinal health. The present study reveals the potential threat of OA to T. tridentatus population and lays a foundation for the further study of the physiological adaptation mechanism of juvenile horseshoe crabs to environmental change.

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Synthesis of Thresholds of Ocean Acidification Impacts on Echinoderms

Frontiers in Marine Science ◽

10.3389/fmars.2021.602601 ◽

2021 ◽

Vol 8 ◽

Author(s):

Nina Bednaršek ◽

Piero Calosi ◽

Richard A. Feely ◽

Richard Ambrose ◽

Maria Byrne ◽

...

Keyword(s):

Ocean Acidification ◽

Growth And Development ◽

Marine Invertebrates ◽

Life Stage ◽

Management Strategies ◽

Confidence Score ◽

Ocean Model ◽

Data Set ◽

Potential Habitat ◽

Ocean Management

Assessing the vulnerability of marine invertebrates to ocean acidification (OA) requires an understanding of critical thresholds at which developmental, physiological, and behavioral traits are affected. To identify relevant thresholds for echinoderms, we undertook a three-step data synthesis, focused on California Current Ecosystem (CCE) species. First, literature characterizing echinoderm responses to OA was compiled, creating a dataset comprised of >12,000 datapoints from 41 studies. Analysis of this data set demonstrated responses related to physiology, behavior, growth and development, and increased mortality in the larval and adult stages to low pH exposure. Second, statistical analyses were conducted on selected pathways to identify OA thresholds specific to duration, taxa, and depth-related life stage. Exposure to reduced pH led to impaired responses across a range of physiology, behavior, growth and development, and mortality endpoints for both larval and adult stages. Third, through discussions and synthesis, the expert panel identified a set of eight duration-dependent, life stage, and habitat-dependent pH thresholds and assigned each a confidence score based on quantity and agreement of evidence. The thresholds for these effects ranged within pH from 7.20 to 7.74 and duration from 7 to 30 days, all of which were characterized with either medium or low confidence. These thresholds yielded a risk range from early warning to lethal impacts, providing the foundation for consistent interpretation of OA monitoring data or numerical ocean model simulations to support climate change marine vulnerability assessments and evaluation of ocean management strategies. As a demonstration, two echinoderm thresholds were applied to simulations of a CCE numerical model to visualize the effects of current state of pH conditions on potential habitat.

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Meta-analysis reveals taxon- and life stage-dependent effects of ocean acidification on marine calcifier feeding performance

10.1101/066076 ◽

2016 ◽

Cited By ~ 2

Author(s):

Jeff C. Clements

Keyword(s):

Ocean Acidification ◽

Early Life ◽

Meta Analysis ◽

Life Stage ◽

Early Life Stage ◽

Effect Sizes ◽

Larval Feeding ◽

Ecosystem Structure ◽

Early Life Stages ◽

Feeding Performance

AbstractWhile ocean acidification is considered among the greatest threats to marine ecosystems, its effects on the feeding performance of marine calcifiers remain uncertain. I conducted a meta-analysis of effect sizes (LnRR) assessing the impacts of acidification on the feeding ability of three groups of marine calcifiers - molluscs, arthropods, and echinoderms. Results suggested taxon-dependent effects of acidification on calcifier feeding performance, with depressed feeding observed for molluscs, echinoderms, and when all taxa were considered. However, ocean acidification had no effect on feeding performance in marine arthropods and larval feeding performance appeared more vulnerable than that of juveniles and adults. Feeding performance was not related to acclimation time nor pCO2 level. This study suggests that the feeding performance of molluscs and early life-stage echinoderms may be depressed in a more acidic ocean, but that arthropod feeding performance is unlikely to suffer. Such changes in feeding performance could contribute to slower growth and development in the early life stages of these organisms and could potentially contribute to changes in community and ecosystem structure where these organisms coexist. Finally, feeding performance could, at least in part, moderate the degree to which molluscs and echinoderms can use food to overcome acidification effects early in life.

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Ocean acidification reduces hardness and stiffness of the Portuguese oyster shell with impaired microstructure: a hierarchical analysis

Biogeosciences ◽

10.5194/bg-15-6833-2018 ◽

2018 ◽

Vol 15 (22) ◽

pp. 6833-6846 ◽

Cited By ~ 15

Author(s):

Yuan Meng ◽

Zhenbin Guo ◽

Susan C. Fitzer ◽

Abhishek Upadhyay ◽

Vera B. S. Chan ◽

...

Keyword(s):

Ocean Acidification ◽

Life Stage ◽

Oyster Shell ◽

Early Life Stage ◽

Marine Organisms ◽

Negative Consequences ◽

Micro Computed Tomography ◽

Ph Homeostasis ◽

Oyster Species ◽

Significant Difference

Abstract. The rapidly intensifying process of ocean acidification (OA) due to anthropogenic CO2 is not only depleting carbonate ions necessary for calcification but also causing acidosis and disrupting internal pH homeostasis in several marine organisms. These negative consequences of OA on marine calcifiers, i.e. oyster species, have been very well documented in recent studies; however, the consequences of reduced or impaired calcification on the end-product, shells or skeletons, still remain one of the major research gaps. Shells produced by marine organisms under OA are expected to show signs of dissolution, disorganized microstructure and reduced mechanical properties. To bridge this knowledge gap and to test the above hypothesis, we investigated the effect of OA on juvenile shells of the commercially important oyster species, Magallana angulata, at ecologically and climatically relevant OA levels (using pH 8.1, 7.8, 7.5, 7.2). In lower pH conditions, a drop of shell hardness and stiffness was revealed by nanoindentation tests, while an evident porous internal microstructure was detected by scanning electron microscopy. Crystallographic orientation, on the other hand, showed no significant difference with decreasing pH using electron back-scattered diffraction (EBSD). These results indicate the porous internal microstructure may be the cause of the reduction in shell hardness and stiffness. The overall decrease of shell density observed from micro-computed tomography analysis indicates the porous internal microstructure may run through the shell, thus inevitably limiting the effectiveness of the shell's defensive function. This study shows the potential deterioration of oyster shells induced by OA, especially in their early life stage. This knowledge is critical to estimate the survival and production of edible oysters in the future ocean.

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