Ocean acidification disrupts induced defences in the intertidal gastropod
            Littorina littorea

Carbon dioxide-induced ocean acidification is predicted to have major implications for marine life, but the research focus to date has been on direct effects. We demonstrate that acidified seawater can have indirect biological effects by disrupting the capability of organisms to express induced defences, hence, increasing their vulnerability to predation. The intertidal gastropod Littorina littorea produced thicker shells in the presence of predation (crab) cues but this response was disrupted at low seawater pH. This response was accompanied by a marked depression in metabolic rate (hypometabolism) under the joint stress of high predation risk and reduced pH. However, snails in this treatment apparently compensated for a lack of morphological defence, by increasing their avoidance behaviour, which, in turn, could affect their interactions with other organisms. Together, these findings suggest that biological effects from ocean acidification may be complex and extend beyond simple direct effects.

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Microplastic leachates impair behavioural vigilance and predator avoidance in a temperate intertidal gastropod

Biology Letters ◽

10.1098/rsbl.2018.0453 ◽

2018 ◽

Vol 14 (11) ◽

pp. 20180453 ◽

Cited By ~ 22

Author(s):

Laurent Seuront

Keyword(s):

Predator Avoidance ◽

Chemical Cues ◽

Biological Effects ◽

Carcinus Maenas ◽

Marine Ecosystems ◽

Behavioural Response ◽

Littorina Littorea ◽

Predator Prey ◽

Marine Life ◽

Intertidal Gastropod

Microplastics are a ubiquitous source of contaminations in marine ecosystems, and have major implications for marine life. Much effort has been devoted to assessing the various effects of microplastics on marine life. No evidence exists, however, on the effects of microplastic leachates on chemically mediated predator–prey interactions and the ability of prey to detect and avoid its predator. This study shows that microplastic leachates have direct biological effects by disturbing the behavioural response of the intertidal gastropod Littorina littorea to the presence of Carcinus maenas chemical cues, hence increasing their vulnerability to predation. Leachates from virgin and beached pellets respectively impaired and inhibited L. littorea vigilance and antipredator behaviours. These results suggest that the biological effects from microplastic leachates may have major implications for marine ecosystems on taxa that rely on chemosensory cues to escape predation.

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Reaction of erythrocyte membranes of animals on direct effects of infrasound

E3S Web of Conferences ◽

10.1051/e3sconf/202015908001 ◽

2020 ◽

Vol 159 ◽

pp. 08001

Author(s):

Sultan Tuleukhanov ◽

Zhanna Abdrassulova ◽

Yerubay Baibekov ◽

Bayan Toyzhigitova ◽

Rabiga Kaliyekper

Keyword(s):

Surface Charge Density ◽

Biological Effects ◽

Erythrocyte Membranes ◽

Differential Count ◽

Combined Effects ◽

Direct Effects ◽

Low Frequencies ◽

Biological Features ◽

Total Differential

This study focuses on the reaction of the membranes of erythrocytes based on the principles that use direct effects of infrasound. The effect on biological features was investigated through the experiments on the rats. The work determined the level of electrical conductivity of blood in rats during direct, indirect and combined effects of infrasound in vivo. There was found that infrasound stimulate the immune system and therefore the results recommend that caution is take place for people who are dealing with these low frequencies. There was used many different technologies and methods, including total differential count in order to consider all of the nuances of the observed object and the main goal. The exposure to infrasound caused increase in the electric conductivity of whole blood than the control in both types of exposure which indicates a large increase of the surface charge density of erythrocyte resulted from the formation of highly reactive species such as superoxide radicals. There were found some undesired biological effects, however further work could have decreased them to a lesser extent.

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Does ocean acidification induce an upward flux of marine aggregates?

Biogeosciences ◽

10.5194/bg-5-1023-2008 ◽

2008 ◽

Vol 5 (4) ◽

pp. 1023-1031 ◽

Cited By ~ 51

Author(s):

X. Mari

Keyword(s):

Ocean Acidification ◽

Atmospheric Carbon Dioxide ◽

New Caledonia ◽

Seawater Acidification ◽

Seawater Ph ◽

Biogenic Carbon ◽

Marine Aggregates ◽

Atmospheric Carbon ◽

Carbon Dioxide Co2 ◽

Sedimentation Processes

Abstract. The absorption of anthropogenic atmospheric carbon dioxide (CO2) by the ocean provokes its acidification. This acidification may alter several oceanic processes, including the export of biogenic carbon from the upper layer of the ocean, hence providing a feedback on rising atmospheric carbon concentrations. The effect of seawater acidification on transparent exopolymeric particles (TEP) driven aggregation and sedimentation processes were investigated by studying the interactions between latex beads and TEP precursors collected in the lagoon of New Caledonia. A suspension of TEP and beads was prepared and the formation of mixed aggregates was monitored as a function of pH under increasing turbulence intensities. The pH was controlled by addition of sulfuric acid. Aggregation and sedimentation processes driven by TEP were drastically reduced when the pH of seawater decreases within the expected limits imposed by increased anthropogenic CO2 emissions. In addition to the diminution of TEP sticking properties, the diminution of seawater pH led to a significant increase of the TEP pool, most likely due to swollen structures. A diminution of seawater pH by 0.2 units or more led to a stop or a reversal of the downward flux of particles. If applicable to oceanic conditions, the sedimentation of marine aggregates may slow down or even stop as the pH decreases, and the vertical flux of organic carbon may reverse. This would enhance both rising atmospheric carbon and ocean acidification.

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Ocean alkalinity enhancement as a tool to mitigate ocean acidification and facilitate CO2 uptake from the atmosphere

10.5194/egusphere-egu21-2264 ◽

2021 ◽

Author(s):

Jakob Rønning ◽

Carolin Löscher

Keyword(s):

Ocean Acidification ◽

Total Alkalinity ◽

Small Scale ◽

Marine Biodiversity ◽

Steady Increase ◽

Co2 Uptake ◽

Seawater Ph ◽

Mineral Additions ◽

Primary Producer ◽

Negative Emission Technologies

Anthropogenic global warming over the last century has led to a steady increase of CO2 in the atmosphere. One of the consequences of increasing CO2 concentrations is ocean acidification, a phenomenon problematic to marine biodiversity and biogeochemistry. The ocean reservoir takes up 25% of CO2 from the atmosphere both chemically and biologically. This potential can be made use of to promote CO2 uptake from the atmosphere while mitigating ocean acidification and protecting biodiversity using negative emission technologies associated with the ocean. We have investigated the potential of various alkaline minerals to stabilize seawater pH overtime on a small scale. Those alkaline minerals were predicted to be appropriate for ocean alkalinity enhancement and can offer a toolset to mitigate CO2 from the atmosphere. Specifically, we have examined how chalk, calcite, dolomite, limestone, and olivine affects seawater pH and total alkalinity (TA) on timescales of several months. Thereby, we could identify two promising minerals, dolomite and olivine, and develop a strategy for mineral additions to buffer the seawater pH. Importantly, the often proposed had an unexpected opposite impact and massively lowered the seawater pH over a timescale of 100 days. The identified advantageous minerals will inform our experiments on primary producer cultures and natural consortia.

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Progressive seawater acidification on the Great Barrier Reef continental shelf

Scientific Reports ◽

10.1038/s41598-020-75293-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Katharina E. Fabricius ◽

Craig Neill ◽

Erik Van Ooijen ◽

Joy N. Smith ◽

Bronte Tilbrook

Keyword(s):

Coral Reefs ◽

Continental Shelf ◽

Great Barrier Reef ◽

Ocean Acidification ◽

Seawater Temperature ◽

Barrier Reef ◽

Saturation State ◽

Seawater Acidification ◽

Seawater Ph ◽

Seawater Samples

Abstract Coral reefs are highly sensitive to ocean acidification due to rising atmospheric CO2 concentrations. We present 10 years of data (2009–2019) on the long-term trends and sources of variation in the carbon chemistry from two fixed stations in the Australian Great Barrier Reef. Data from the subtropical mid-shelf GBRWIS comprised 3-h instrument records, and those from the tropical coastal NRSYON were monthly seawater samples. Both stations recorded significant variation in seawater CO2 fugacity (fCO2), attributable to seasonal, daytime, temperature and salinity fluctuations. Superimposed over this variation, fCO2 progressively increased by > 2.0 ± 0.3 µatm year−1 at both stations. Seawater temperature and salinity also increased throughout the decade, whereas seawater pH and the saturation state of aragonite declined. The decadal upward fCO2 trend remained significant in temperature- and salinity-normalised data. Indeed, annual fCO2 minima are now higher than estimated fCO2 maxima in the early 1960s, with mean fCO2 now ~ 28% higher than 60 years ago. Our data indicate that carbonate dissolution from the seafloor is currently unable to buffer the Great Barrier Reef against ocean acidification. This is of great concern for the thousands of coral reefs and other diverse marine ecosystems located in this vast continental shelf system.

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Ocean acidification disrupts the orientation of postlarval Caribbean spiny lobsters

Scientific Reports ◽

10.1038/s41598-020-75021-9 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Philip M. Gravinese ◽

Heather N. Page ◽

Casey B. Butler ◽

Angelo Jason Spadaro ◽

Clay Hewett ◽

...

Keyword(s):

Ocean Acidification ◽

Time Scales ◽

Coastal Waters ◽

Chemical Cues ◽

Spiny Lobster ◽

Episodic Acidification ◽

Anthropogenic Inputs ◽

Seawater Ph ◽

Y Maze ◽

The Caribbean

Abstract Anthropogenic inputs into coastal ecosystems are causing more frequent environmental fluctuations and reducing seawater pH. One such ecosystem is Florida Bay, an important nursery for the Caribbean spiny lobster, Panulirus argus. Although adult crustaceans are often resilient to reduced seawater pH, earlier ontogenetic stages can be physiologically limited in their tolerance to ocean acidification on shorter time scales. We used a Y-maze chamber to test whether reduced-pH seawater altered the orientation of spiny lobster pueruli toward chemical cues produced by Laurencia spp. macroalgae, a known settlement cue for the species. We tested the hypothesis that pueruli conditioned in reduced-pH seawater would be less responsive to Laurencia spp. chemical cues than pueruli in ambient-pH seawater by comparing the proportion of individuals that moved to the cue side of the chamber with the proportion that moved to the side with no cue. We also recorded the amount of time (sec) before a response was observed. Pueruli conditioned in reduced-pH seawater were less responsive and failed to select the Laurencia cue. Our results suggest that episodic acidification of coastal waters might limit the ability of pueruli to locate settlement habitats, increasing postsettlement mortality.

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The other ocean acidification problem: CO 2 as a resource among competitors for ecosystem dominance

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2012.0442 ◽

2013 ◽

Vol 368 (1627) ◽

pp. 20120442 ◽

Cited By ~ 146

Author(s):

Sean D. Connell ◽

Kristy J. Kroeker ◽

Katharina E. Fabricius ◽

David I. Kline ◽

Bayden D. Russell

Keyword(s):

Coral Reefs ◽

Ocean Acidification ◽

Atmospheric Carbon Dioxide ◽

Environmental Changes ◽

Kelp Forests ◽

Direct Effects ◽

Species Dominance ◽

Tropical Conditions ◽

Near Future

Predictions concerning the consequences of the oceanic uptake of increasing atmospheric carbon dioxide (CO 2 ) have been primarily occupied with the effects of ocean acidification on calcifying organisms, particularly those critical to the formation of habitats (e.g. coral reefs) or their maintenance (e.g. grazing echinoderms). This focus overlooks direct and indirect effects of CO 2 on non-calcareous taxa that play critical roles in ecosystem shifts (e.g. competitors). We present the model that future atmospheric [CO 2 ] may act as a resource for mat-forming algae, a diverse and widespread group known to reduce the resilience of kelp forests and coral reefs. We test this hypothesis by combining laboratory and field CO 2 experiments and data from ‘natural’ volcanic CO 2 vents. We show that mats have enhanced productivity in experiments and more expansive covers in situ under projected near-future CO 2 conditions both in temperate and tropical conditions. The benefits of CO 2 are likely to vary among species of producers, potentially leading to shifts in species dominance in a high CO 2 world. We explore how ocean acidification combines with other environmental changes across a number of scales, and raise awareness of CO 2 as a resource whose change in availability could have wide-ranging community consequences beyond its direct effects.

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Near-shore Antarctic pH variability has implications for the design of oceanacidification experiments

Scientific Reports ◽

10.1038/srep09638 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 41

Author(s):

Lydia Kapsenberg ◽

Amanda L. Kelley ◽

Emily C. Shaw ◽

Todd R. Martz ◽

Gretchen E. Hofmann

Keyword(s):

Time Series ◽

Ocean Acidification ◽

Marine Species ◽

Physiological Data ◽

Ph Change ◽

Physiological Tolerance ◽

Seawater Ph ◽

Near Shore ◽

Ecosystem Changes

Abstract Understanding how declining seawater pH caused by anthropogenic carbon emissions, or oceanacidification, impacts Southern Ocean biota is limited by a paucity of pH time-series. Here,we present the first high-frequency in-situ pH time-series in near-shore Antarctica fromspring to winter under annual sea ice. Observations from autonomous pH sensors revealed aseasonal increase of 0.3 pH units. The summer season was marked by an increase in temporalpH variability relative to spring and early winter, matching coastal pH variability observedat lower latitudes. Using our data, simulations of ocean acidification show a future periodof deleterious wintertime pH levels potentially expanding to 7–11 months annually by 2100.Given the presence of (sub)seasonal pH variability, Antarctica marine species have anexisting physiological tolerance of temporal pH change that may influence adaptation tofuture acidification. Yet, pH-induced ecosystem changes remain difficult to characterize inthe absence of sufficient physiological data on present-day tolerances. It is thereforeessential to incorporate natural and projected temporal pH variability in the design ofexperiments intended to study ocean acidification biology.

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