Archive for January, 2021

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Long-term emissions cuts are needed to slow ocean acidification

Published 6 January 2021 Media coverage Closed

During the first half of 2020, global greenhouse gas emissions dropped by about nine percent in the midst of the COVID-19 outbreak. People around the world reported seeing signs that “nature was healing” as a result of a steep decline in human activities such as transportation and production. 

However, a new study from UC Boulder has shown that the positive changes seen in natural ecosystems were not reflected throughout Earth’s oceans. 

Professor Nicole Lovenduski reports that there were no significant reductions in ocean acidification as a result of lower emissions. Even if emissions had been reduced at four times the rate in the first half of last year, changes in the ocean would have been barely noticeable, according to the study.

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Promoting ocean acidification awareness and research in Africa

Published 6 January 2021 Meetings Closed

At the upcoming OA Day of Action to be held in Liberia, OA-Africa is hosting a side event event in partnership withThe Ocean Foundation, the IAEA OA-ICC, Future Earth Coasts, Environmental Protection Agency of Liberia, National Fisheries and Aquaculture Authority, and the Liberia Maritime Authority. The objective of the OA-Africa side event is to promote and facilitate a community of awareness around ocean acidification to communicate, develop, and facilitate international activities on ocean acidification, including science, capacity building, and communication. We find that the work on ocean acidification is better appreciated when scientists, industry practitioners, and policymakers collaborate and speak a common language.

The Ocean Acidification Day of Action will be hosted by the National Fisheries and Aquaculture Authority (NaFAA) and Environmental Protection Agency (EPA) of Liberia in cooperation with the Ocean Acidification International Coordination Center (OA-ICC).

Ocean acidification often referred to as “the other CO2 problem”, is a perturbation of ocean chemistry as a consequence of human CO2 emission. It has been shown to be a major threat to marine ecosystems worldwide, and is the focus of the UN Sustainable Development Goal (SDG) 14.3. Since 2015, African scientists are actively collaborating to address this issue by advancing ocean acidification research throughout the continent as part of the OA-Africa network.

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Chercheur sur les réponses écophysiologiques des bivalves marins aux changements globaux (H/F) (French)

Published 6 January 2021 Jobs Closed

Lieu de travail Argenton – Bretagne – France

Champ: scientifique

Principal: Biologie

Date: limite de candidature  07/02/2021

Fonction: Recherche et Développement

Employeur

L’Ifremer

Reconnu dans le monde entier comme l’un des tout premiers instituts en sciences et technologies marines, l’Ifremer s’inscrit dans une double perspective de développement durable et de science ouverte. Il mène des recherches, innove, produit des expertises pour protéger et restaurer l’océan, exploiter ses ressources de manière responsable, et partager les connaissances et les données marines afin de créer de nouvelles opportunités pour une croissance économique respectueuse du milieu marin.

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Ocean acidification: why the Earth’s oceans are turning to acid

Published 6 January 2021 Web sites and blogs 1 Comment

It’s a known fact that climate change and global warming are making our planet warmer each year. These rising global temperatures don’t just affect human and terrestrial animal life, however; they also affect our planet’s oceans — an expansive environment that accounts for more than 70 percent of the entire globe. Unfortunately, that isn’t the ocean’s only problem these days. The ocean’s pH is changing gradually over time, and what causes ocean acidification may be directly related to what’s causing climate change as well. 

What causes ocean acidification?

According to paleontologist Professor Richard Twitchett, carbon dioxide that is present in the atmosphere dissolves into the ocean, thereby lowering itCs pH and causing it to become more acidic. There are many factors that contribute to rising carbon dioxide levels, things like air pollution that results from the burning of fossil fuels. Burning coal, oil, and gas for heat or energy, sends smog up into the atmosphere, and that smog is loaded with CO2. 

Continue reading ‘Ocean acidification: why the Earth’s oceans are turning to acid’

Evaluating bloom potential of the green-tide forming alga Ulva ohnoi under ocean acidification and warming

Published 6 January 2021 Science Closed
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Highlights

Mesocosm was conducted to evaluate bloom potential of U. ohnoi in the future ocean.

Bloom potential was higher in ocean acidification with improved C and N metabolism.

Positive metabolic change in ocean acidification were offset by elevated temperature.

The bloom potential decreases when acidification and warming are combined.

Abstract

The occurrence of green-tides, whose bloom potential may be increased by various human activities and biogeochemical process, results in enormous economic losses and ecosystem collapse. In this study, we investigated the ecophysiology of the subtropical green-tide forming alga, Ulva ohnoi complex (hereafter: U. ohnoi), under simulated future ocean conditions in order to predict its bloom potential using photosynthesis and growth measurements, and stable isotope analyses. Our mesocosm system included four experimental conditions that simulated the individual and combined effects of elevated CO2 and temperature, namely control (450 μatm CO2 & 20oC), acidification (900 μatm CO2 & 20oC), warming (450 μatm CO2 & 25oC), and greenhouse (900 μatm CO2 & 25oC). Photosynthetic electron transport rates (rETR) increased significantly under acidification conditions, but net photosynthesis and growth were not affected. In contrast, rETR, net photosynthesis, and growth all decreased significantly under elevated temperature conditions (i.e. both warming and greenhouse). These results represent the imbalance of energy metabolism between electron transport and O2 production that may be expected under ocean acidification conditions. This imbalance appears to be related to carbon and nitrogen assimilation by U. ohnoi. In particular, 13C and 15N discrimination data suggest U. ohnoi prefers CO2 and NH4+ over HCO3– and NO3– as sources of carbon and nitrogen, respectively, and this results in increased N content in the thallus under ocean acidification conditions. Together, our results suggest a trade-off in which the bloom potential of U. ohnoi could increase under ocean acidification due to greater N accumulation and through the saving of energy during carbon and nitrogen metabolism, but that elevated temperatures could decrease U. ohnoi’s bloom potential through a decrease in photosynthesis and growth.

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Life-long coral skeletal acclimatization at CO2 vents in Papua New Guinea reveals species- and environment-specific effects

Published 6 January 2021 Science Closed
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The responses of corals and other marine calcifying organisms to ocean acidification (OA) are variable and span from no effect to severe responses. Here we investigated the effect of long-term exposure to OA on skeletal parameters of four tropical zooxanthellate corals living at two CO2 vents in Papua New Guinea, namely in Dobu and Upa Upasina. The skeletal porosity of Galaxea fascicularis, Acropora millepora, and Pocillopora damicornis was higher (from 17% to 38%, depending on the species) at the seep site compared to the control only at Upa Upasina. Massive Porites showed no differences at any of the locations. Pocillopora damicornis also showed a ~ 7% decrease of micro-density and an increase of the volume fraction of the larger pores, a decrease of the intraskeletal organic matrix content with an increase of the intraskeletal water content, and no variation in the organic matrix related strain and crystallite size. The fact that the skeletal parameters varied only at one of the two seep sites suggests that other local environmental conditions interact with OA to modify the coral skeletal parameters. This might also contribute to explain the great deal of responses to OA reported for corals and other marine calcifying organisms.

Continue reading ‘Life-long coral skeletal acclimatization at CO2 vents in Papua New Guinea reveals species- and environment-specific effects’

American lobster postlarvae alter gene regulation in response to ocean warming and acidification

Published 5 January 2021 Science Closed
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Anthropogenic carbon emissions released into the atmosphere is driving rapid, concurrent increases in temperature and acidity across the world’s oceans. Disentangling the interactive effects of warming and acidification on vulnerable life stages is important to our understanding of responses of marine species to climate change. This study evaluates the interactive effects of these stressors on the acute response of gene expression of postlarval American lobster (Homarus americanus), a species whose geographic range is warming and acidifying faster than most of the world’s oceans. In the context of our experiment, we found two especially noteworthy results: First, although physiological end points have consistently been shown to be more responsive to warming in similar experimental designs, our study found gene regulation to be considerably more responsive to elevated pCO2. Furthermore, the combined effect of both stressors on gene regulation was significantly greater than either stressor alone. Using a full factorial experimental design, lobsters were raised in control and elevated pCO2 concentrations (400 ppm and 1,200 ppm) and temperatures (16°C and 19°C). A transcriptome was assembled from an identified 414,517 unique transcripts. Overall, 1,108 transcripts were differentially expressed across treatments, several of which were related to stress response and shell formation. When temperature alone was elevated (19°C), larvae downregulated genes related to cuticle development; when pCO2 alone was elevated (1,200 ppm), larvae upregulated chitinase as well as genes related to stress response and immune function. The joint effects of end‐century stressors (19°C, 1,200 ppm) resulted in the upregulation of those same genes, as well as cellulase, the downregulation of calcified cuticle proteins, and a greater upregulation of genes related to immune response and function. These results indicate that changes in gene expression in larval lobster provide a mechanism to respond to stressors resulting from a rapidly changing environment.

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Elevated acidification rates due to deposition of atmospheric pollutants in the coastal Bay of Bengal

Published 5 January 2021 Science Closed
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Human inputs of pollutants to the atmosphere and subsequent deposition may decrease pH in the coastal waters. Significant rate of decrease in pH and increase in pCO2 by 3 to 5 times is noticed in the coastal Bay of Bengal (BoB) than the global trend in the last few decades. We provide evidence for the first time for a rapid decrease in surface water pH due to atmospheric deposition of pollutants in the coastal BoB. The decrease in pH in the coastal BoB over the last decade is associated with concomitant increase in aerosol optical depth (AOD), total suspended particles (TSP) in air, sulphate and nitrate concentrations in TSP. This study suggests that contamination of surface coastal BoB by atmospheric pollutants not only acidifies surface ocean but also potentially amplifies CO2 emission with immediate implications to regional weather and climate.

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Use of a simple empirical model for the accurate conversion of the seawater pH value measured with NIST calibration into seawater pH scales

Published 5 January 2021 Science Closed
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The seawater pH measurement is usually quite complicated because that matrix is characterized by a high ionic strength leading to calibration errors if NIST standards are used. For this matrix, different pH scales like the “total hydrogen ion concentration scale” (TOT) and the “seawater scale” (SWS), are defined, and suitable synthetic seawater solutions must be prepared according to standard procedures to calibrate the glass electrode. This work provides a new approach to make seawater pH measurements by using the glass electrode calibrated with the NIST standards (pHNIST) converting the pHNIST into the right TOT or SWS scales by using empirical equations derived from theoretical thermodynamic data: 

pHTOT=pHNIST+0.10383+4.33⋅10−5TS+3.633⋅10−5T2−4.921⋅10−5S2, and pHSWS=pHNIST+0.097733+4.1059⋅10−5TS+3.5437⋅10−5T2−4.941⋅10−5S2,

for the TOT and SWS scales, respectively. These equations are functions of two simple experimental parameters, namely, T = temperature (°C) and S = salinity (PSU, (g/L), Practical Salinity Units). These equations were experimentally validated and the uncertainty of pHTOT and pHSWS was demonstrated to have no statistical difference with the corresponding values obtained following the standard operative procedure (SOP) using commercially unavailable seawater-like buffers. The proposed method has therefore the same performances and it is largely preferable as it avoids long and tedious procedures of the synthetic seawater preparations.

Continue reading ‘Use of a simple empirical model for the accurate conversion of the seawater pH value measured with NIST calibration into seawater pH scales’

Ocean and coastal indicators: understanding and coping with climate change at the land-sea interface

Published 5 January 2021 Science Closed
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The U.S. Exclusive Economic Zone (EEZ) encompasses approximately 3.4 million square nautical miles of ocean and a coastline of over 12,300 miles. Along with the Great Lakes, this vast area generates ~US 370 billion of U.S. gross domestic product, 617 billion in sales and 2.6 million jobs each year. These ocean and coastal ecosystems also provide many important non-market services including subsistence food provisioning, health benefits, shoreline protection, climate regulation, conservation of marine biodiversity, and preservation of cultural heritage. As climatic changes occur, these benefits or ecosystem services may be significantly reduced or in some cases enhanced. These services are also under an array of pressures including over-exploitation of natural resources, pollution, and land use changes that occur simultaneously in synergistic, multiplicative, or antagonistic ways. This results in direct and indirect impacts that are often unpredictable across spatial and temporal scales. Here, we discuss a set of indicators designed in close collaboration with the U.S. National Climate Indicators System. Tracking the impacts via indicators will be essential to ensure long-term health of the marine environment and sustain the benefits to stakeholders who depend on marine ecosystem services.

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CO2-system observations from a mooring on the West Antarctic Peninsula continental shelf

Published 5 January 2021 Science Closed
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These are CO2-system data from a mooring deployed on the continental shelf of the West Antarctic Peninsula (latitude: 66.5S, longitude: 69.9W), at station 300.100 of the Palmer Long-Term Ecological Research (PAL-LTER) sampling grid (https://pal.lternet.edu). Temperature, salinity, and pH were acquired by using an SBE SeapHOx sensor ~18m below the surface with 3-hourly resolution from January 2018 to January 2019. Sensor data were averaged to 24-hour resolution. The salinity sensor failed in May 2018, and mean value between the start of the deployment and the last observation is used to populate the remainder of the record. The pH data were combined with salinity and the relationship between alkalinity and salinity of Hauri et al., 2015 to compute the partial pressure of CO2 (pCO2). The data are in comma-separated (csv) format with units in the first row of the file.

Also available are discrete dissolved inorganic carbon (TCO2) and alkalinity samples from CTD profiles collected at the mooring station and analysed following standard procedures at the Virginia Institute of Marine Science. A detailed description of sample collection and analytical methods is given in Shadwick et al., (under review). There is one comma separated file (csv) per cruise; variable names and units are in the first row.

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Conodont calcium isotopic evidence for multiple shelf acidification events during the early Triassic

Published 5 January 2021 Science Closed
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Highlights

  • Conodont δ44/40Ca curve is established for the latest Permian to Middle Triassic.
  • Three episodes of decreasing δ44/40Ca (0.16–0.23‰) occurred in the Early Triassic.
  • Negative δ44/40Ca shift in the PTB suggests a CO2-driven ocean acidification event.
  • Negative δ44/40Ca shifts in SSB & OAB suggest upwelling-driven shelf acidification.

Abstract

The marine calcium (Ca) cycle is controlled by rates of continental weathering, seawater pH, and carbonate deposition on the seafloor and is linked to atmospheric CO2, climate change, and marine biotic evolution. Here, we provide the first continuous seawater Ca isotope profile from conodont apatite in South China for the latest Permian to early Middle Triassic, revealing major fluctuations in the Early Triassic calcium cycle. Three episodes of decreasing conodont δ44/40Ca (by 0.16–0.23‰) occurred around the Permian-Triassic, Smithian-Spathian, and Olenekian-Anisian boundaries. The first episode, coincident with a negative excursion of carbonate carbon isotopes, global warming, oceanic anoxia, enhanced weathering, and sea-level fall, was likely caused by a combination of volcanic CO2 release, ocean acidification, a reduced skeletal carbonate sink, and enhanced weathering of shelf carbonates. The latter two episodes, coincident with positive excursions of carbon isotopes, global cooling, and oceanic anoxia, possibly resulted from upwelling-driven shelf acidification and reduced skeletal carbonate burial. All three events were associated with marine biotic diversity losses, demonstrating a link between the calcium cycle and mass extinctions.

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Hearing: ocean acidification commission

Published 4 January 2021 Media coverage Closed

Event Details

Status: Rescheduled

Event Date: Original Start Date: Tuesday, December 8, 2020  Friday, January 8, 2021

Start Time: 3:00 PM

Location: Virtual Hearing

Event Description: Ocean Acidification Public Hearing and Commission Meeting

Title: Ocean Acidification Public Hearing and Commission Meeting

Agenda: 

3pm-4pm: Public hearing on the draft Ocean Acidification report

4pm-5pm: Vote on the final commission report

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Effects of experimental ocean acidification on the larval morphology and metabolism of a temperate Sparid, Chrysoblephus laticeps

Published 4 January 2021 Science Closed
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Ocean acidification is predicted to have widespread impacts on marine species. The early life stages of fishes, being particularly sensitive to environmental deviations, represent a critical bottleneck to recruitment. We investigated the effects of ocean acidification (∆pH = −0.4) on the oxygen consumption and morphometry during the early ontogeny of a commercially important seabream, Chrysoblephus laticeps, up until flexion. Hatchlings appeared to be tolerant to hypercapnic conditions, exhibiting no difference in oxygen consumption or morphometry between treatments, although the yolk reserves were marginally reduced in the low-pH treatment. The preflexion stages appeared to undergo metabolic depression, exhibiting lower metabolic rates along with lower growth metrics in hypercapnic conditions. However, although the sample sizes were low, the flexion-stage larvae exhibited greater rates of metabolic and growth metric increases in hypercapnic conditions. This study shows that the effects of OA may be stage specific during early ontogeny and potentially related to the development of crucial organs, such as the gills. Future studies investigating the effects of climate change on fish larvae should endeavour to include multiple developmental stages in order to make more accurate predictions on recruitment dynamics for the coming decades.

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An updated version of the global interior ocean biogeochemical data product, GLODAPv2.2020

Published 4 January 2021 Science Closed
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The Global Ocean Data Analysis Project (GLODAP) is a synthesis effort providing regular compilations of surface-to-bottom ocean biogeochemical data, with an emphasis on seawater inorganic carbon chemistry and related variables determined through chemical analysis of seawater samples. GLODAPv2.2020 is an update of the previous version, GLODAPv2.2019. The major changes are data from 106 new cruises added, extension of time coverage to 2019, and the inclusion of available (also for historical cruises) discrete fugacity of CO2 (fCO2) values in the merged product files. GLODAPv2.2020 now includes measurements from more than 1.2 million water samples from the global oceans collected on 946 cruises. The data for the 12 GLODAP core variables (salinity, oxygen, nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity, pH, CFC-11, CFC-12, CFC-113, and CCl4) have undergone extensive quality control with a focus on systematic evaluation of bias. The data are available in two formats: (i) as submitted by the data originator but updated to WOCE exchange format and (ii) as a merged data product with adjustments applied to minimize bias. These adjustments were derived by comparing the data from the 106 new cruises with the data from the 840 quality-controlled cruises of the GLODAPv2.2019 data product using crossover analysis. Comparisons to empirical algorithm estimates provided additional context for adjustment decisions; this is new to this version. The adjustments are intended to remove potential biases from errors related to measurement, calibration, and data-handling practices without removing known or likely time trends or variations in the variables evaluated. The compiled and adjusted data product is believed to be consistent to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1 in total alkalinity, 0.01–0.02 in pH (depending on region), and 5 % in the halogenated transient tracers. The other variables included in the compilation, such as isotopic tracers and discrete fCO2, were not subjected to bias comparison or adjustments.

The original data and their documentation and DOI codes are available at the Ocean Carbon Data System of NOAA NCEI (https://www.nodc.noaa.gov/ocads/oceans/GLODAPv2_2020/, last access: 20 June 2020). This site also provides access to the merged data product, which is provided as a single global file and as four regional ones – the Arctic, Atlantic, Indian, and Pacific oceans – under https://doi.org/10.25921/2c8h-sa89 (Olsen et al., 2020). These bias-adjusted product files also include significant ancillary and approximated data. These were obtained by interpolation of, or calculation from, measured data. This living data update documents the GLODAPv2.2020 methods and provides a broad overview of the secondary quality control procedures and results.

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Antarctic ecosystems in transition – life between stresses and opportunities

Published 4 January 2021 Science Closed
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Important findings from the second decade of the 21st century on the impact of environmental change on biological processes in the Antarctic were synthesized by 26 international experts. Ten key messages emerged that have stakeholder-relevance and/or a high impact for the scientific community. They address (i) altered biogeochemical cycles, (ii) ocean acidification, (iii) climate change hotspots, (iv) unexpected dynamism in seabed-dwelling populations, (v) spatial range shifts, (vi) adaptation and thermal resilience, (vii) sea ice related biological fluctuations, (viii) pollution, (ix) endangered terrestrial endemism and (x) the discovery of unknown habitats. Most Antarctic biotas are exposed to multiple stresses and considered vulnerable to environmental change due to narrow tolerance ranges, rapid change, projected circumpolar impacts, low potential for timely genetic adaptation, and migration barriers. Important ecosystem functions, such as primary production and energy transfer between trophic levels, have already changed, and biodiversity patterns have shifted. A confidence assessment of the degree of ‘scientific understanding’ revealed an intermediate level for most of the more detailed sub-messages, indicating that process-oriented research has been successful in the past decade. Additional efforts are necessary, however, to achieve the level of robustness in scientific knowledge that is required to inform protection measures of the unique Antarctic terrestrial and marine ecosystems, and their contributions to global biodiversity and ecosystem services.

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Chapter: Manipulation of seawater carbonate chemistry

Published 4 January 2021 Science Closed
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Different culture methods to grow microalgae could lead to different physical (light) and chemical environments in culture vessels. Photosynthetic carbon sequestration by the algae in light and their respiratory CO2 release in darkness, can affect stability of carbonate systems (pH, various forms of inorganic carbon, total alkalinity) in culture systems. Usually, pH could increase during light period with active photosynthesis, and decrease during dark period. Such changes in pH and associated carbonate chemistry depend on culture methods and cell biomass or densities of microalgae in water body. The greater the amount of carbon fixation in the water, the greater the changes of the carbonate system. In experiments on the influence of other environmental factors on algae, controlling pH and other carbonate system parameters within known stable ranges is one of the keys to obtain reliable data. This section introduces the seawater carbonate system, compares the existing several kinds of carbonate system control methods, and provides basic suggestions for ocean acidification simulation experiments on marine organisms.

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Establishing ocean acidification monitoring system for tropical waters of Indonesia facing regional climate variability

Published 4 January 2021 Science Closed
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Emission of greenhouse gasses, including high CO2 and other materials, initiating global warming and climate change. Atmospheric CO2 that affect the carbonate system of seawater cause ocean acidification. Indonesian sea with a unique geolocation has important role in this emerging phenomenon. Ocean acidification (OA) not only affect marine organism as a direct effect but also economic and ecological for the human being. Considering the high impact of OA and following the global responsibility on Sustainable Development Goals, it is necessary to conduct systematic research and monitoring on OA in Indonesia. In this review, we are informing the urgency of the OA monitoring system and suggest the carbonate system monitoring as well as carbon biogeochemistry studies for OA. We also introduce an initiative of biogeochemical monitoring for OA at Lombok island with the established protocols. Improvement of many aspects including analysis instrumentations, analysis method, sample treatment, and sampling frequency will be a new insight in conducting further research and monitoring of OA.

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Juvenile Eastern oysters more resilient to extreme ocean acidification than their mud crab predators

Published 4 January 2021 Science Closed
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Ocean acidification is predicted to impair marine calcifiers’ abilities to produce shells and skeletons. We conducted laboratory experiments investigating the impacts of CO2‐induced ocean acidification (pCO2 = 478 – 519, 734 – 835, 8980 – 9567; Ωcalcite = 7.3 – 5.7, 5.6 – 4.3, 0.6 – 0.7) on calcification rates of two estuarine calcifiers involved in a classic predator‐prey model system: adult Panopeus herbstii (Atlantic mud crab) and juvenile Crassostrea virginica (eastern oyster). Both oyster and crab calcification rates significantly decreased at the highest pCO2 level. Notably, however, oysters maintained positive net calcification rates in the highest pCO2 treatment that was undersaturated with respect to calcite, while mud crabs exhibited net dissolution (i.e., net loss of shell mass) in calcite‐undersaturated conditions. Secondary electron imaging of oyster shells revealed minor microstructural alterations in the moderate‐pCO2 treatment, and major micro‐ and macro‐structural changes (including shell dissolution, delamination of periostracum) in the high‐pCO2 treatment. These results underscore the threat that ocean acidification poses for marine organisms that produce calcium carbonate shells, illustrate the strong biological control that some marine calcifiers exert over their shell‐building process, and shows that ocean acidification differentially impacts the crab and oyster species involved in this classical predator‐prey model system.

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Ocean acidification inhibits the sperm motility of Tegillarca granosavia disturbing ATP synthesis and intracellular CA2+ activity (Chinese)

Published 4 January 2021 Science Closed
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Since the industrial revolution, massive amount of anthropogenic carbon dioxide (CO2) have been generated to elevate the atmospheric CO2 concentration. Some anthropogenic CO2 have been absorbed by the ocean to cause “ocean acidification” (OA). Although the negative impacts of OA on sperm motility are increasingly found in various marine invertebrate species, the cellular and molecular mechanisms for these effects are still poorly understood. This study investigated the effect of OA (pH7.8 and 7.4) on sperm motility and energy supplying pathway in blood clam Tegillarca granosa. The results showed that the sperm swimming speed reduced significantly in acidified seawater. Since the adenosine triphosphate (ATP) level of sperm is closely related to its motility, we analyzed the sperm ATP content and activities of key enzymes during ATP synthesis under different OA scenarios. OA treatments significantly reduced ATP content as well as activities of 6-phosphofructokinase and pyruvate kinase in the sperm of T. granosa. The sperm Ca2+-ATPase of various animals has been reported to regulate sperm motility. Therefore, we explored the Ca2+-ATPase activity of T. granosa sperm under OA treatment. The results found that Ca2+-ATPase activities in the sperm of T. granosa were significantly declined under OA scenarios. In conclusion, these results suggested that OA could constrain sperm motility through inhibiting ATP synthesis and disturbing intracellular Ca2+ regulation.

Continue reading ‘Ocean acidification inhibits the sperm motility of Tegillarca granosavia disturbing ATP synthesis and intracellular CA2+ activity (Chinese)’

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