scholarly journals The physiological response of the deep-sea coralSolenosmilia variabilisto ocean acidification

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5236 ◽  
Author(s):  
Malindi J. Gammon ◽  
Dianne M. Tracey ◽  
Peter M. Marriott ◽  
Vonda J. Cummings ◽  
Simon K. Davy
Keyword(s):  
Ocean Acidification ◽  
Deep Sea ◽  
Exposure Period ◽  
Physiological Processes ◽  
Seawater Ph ◽  
Flow Through ◽  
Seamount Chain ◽  
Colour Saturation ◽  
And Control

Several forms of calcifying scleractinian corals provide important habitat complexity in the deep-sea and are consistently associated with a high biodiversity of fish and other invertebrates. How these corals may respond to the future predicted environmental conditions of ocean acidification is poorly understood, but any detrimental effects on these marine calcifiers will have wider impacts on the ecosystem. Colonies ofSolenosmilia variabilis, a protected deep-sea coral commonly occurring throughout the New Zealand region, were collected during a cruise in March 2014 from the Louisville Seamount Chain. Over a 12-month period, samples were maintained in temperature controlled (∼3.5 °C) continuous flow-through tanks at a seawater pH that reflects the region’s current conditions (7.88) and an end-of-century scenario (7.65). Impacts on coral growth and the intensity of colour saturation (as a proxy for the coenenchyme tissue that covers the coral exoskeleton and links the coral polyps) were measured bimonthly. In addition, respiration rate was measured after a mid-term (six months) and long-term (12 months) exposure period. Growth rates were highly variable, ranging from 0.53 to 3.068 mm year−1and showed no detectable difference between the treatment and control colonies. Respiration rates also varied independently of pH and ranged from 0.065 to 1.756 µmol O2g protein−1h−1. A significant change in colour was observed in the treatment group over time, indicating a loss of coenenchyme. This loss was greatest after 10 months at 5.28% and could indicate a reallocation of energy with physiological processes (e.g.  growth and respiration) being maintained at the expense of coenenchyme production. This research illustrates important first steps to assessing and understanding the sensitivity of deep-sea corals to ocean acidification.

scholarly journals Corals and Carbon: The physiological response of a protected deep-sea coral (Solenosmilia variabilis) to ocean acidification

2021 ◽  
Author(s):  
◽  
Malindi Gammon
Keyword(s):  
Treatment Group ◽  
Ocean Acidification ◽  
Deep Sea ◽  
Exposure Period ◽  
Interactive Effects ◽  
Tissue Loss ◽  
Control Group ◽  
Respiration Rates ◽  
Deep Sea Corals

<p>Calcifying corals provide important habitat complexity in the deep-sea and are consistently associated with a biodiversity of fish and other invertebrates. Little is understood about how deep-sea corals may respond to predicted scenarios of ocean acidification (OA), but any predicted changes will have wider impacts on the ecosystem.   Colonies of Solenosmilia variabilis, a species of deep-sea coral found in the waters surrounding New Zealand, were collected during a cruise in March 2014 from the Louisville Seamount chain. Over 12-months, coral samples were maintained in temperature controlled (~3.5°C) continuous flow-through tanks. A control group of coral colonies was held in seawater with pH 7.88 and a treatment group in pH 7.65. These two pH levels were designed to reflect current pH conditions and end-of-century conditions, respectively. In addition to investigating changes in growth and morphology, measurements of respiration and intracellular pH (pHi) were taken after a mid-term (6 months for respiration; 9 months for pHi) and long-term (12 months for both respiration and pHi) exposure period. An established method used in measuring the pHi of shallow water corals was adapted for use with deep-sea corals for the first time. pHi was independent from the seawater treatment and ranged from 7.67 – 8.30. Respiration rate was not influenced by the reduced seawater pH tested here. Respiration rates were highly variable, ranging from 0.065 to 1.756 μg O2 g-1 protein h-1 and pHi ranged from 7.67 – 8.30. Yearly growth rates were also variable, ranging from 0.53 to 3.068 mm year-1, and again showed no detectable difference between the treatment and control colonies. However, a loss in the colouration of coral skeletons was observed in the treatment group and was attributed to a loss of tissue. This could indicate a reallocation of energy, allowing for the maintenance of those other physiological parameters measured here (e.g. growth and respiration rates). If this is indeed occurring, it would be consistent with the idea of phenotypic plasticity, where corals can alternate between soft-bodied and fossilizing forms, allowing them to survive past periods of environmental stress.   This research is an important first step towards understanding the sensitivity of deep-sea corals to OA and the potential for acclimation, and suggests that in many respects, S. variabilis might not be susceptible to end-of-century projections of OA. Nevertheless, the observed tissue loss is interesting and warrants further investigation to assess its long-term implications. Furthermore, the impacts of greater levels of OA, and the interactive effects of other ecological parameters such as food availability, need to be tested.</p>

scholarly journals Corals and Carbon: The physiological response of a protected deep-sea coral (Solenosmilia variabilis) to ocean acidification

2021 ◽  
Author(s):  
◽  
Malindi Gammon
Keyword(s):  
Treatment Group ◽  
Ocean Acidification ◽  
Deep Sea ◽  
Exposure Period ◽  
Interactive Effects ◽  
Tissue Loss ◽  
Control Group ◽  
Respiration Rates ◽  
Deep Sea Corals

<p>Calcifying corals provide important habitat complexity in the deep-sea and are consistently associated with a biodiversity of fish and other invertebrates. Little is understood about how deep-sea corals may respond to predicted scenarios of ocean acidification (OA), but any predicted changes will have wider impacts on the ecosystem.   Colonies of Solenosmilia variabilis, a species of deep-sea coral found in the waters surrounding New Zealand, were collected during a cruise in March 2014 from the Louisville Seamount chain. Over 12-months, coral samples were maintained in temperature controlled (~3.5°C) continuous flow-through tanks. A control group of coral colonies was held in seawater with pH 7.88 and a treatment group in pH 7.65. These two pH levels were designed to reflect current pH conditions and end-of-century conditions, respectively. In addition to investigating changes in growth and morphology, measurements of respiration and intracellular pH (pHi) were taken after a mid-term (6 months for respiration; 9 months for pHi) and long-term (12 months for both respiration and pHi) exposure period. An established method used in measuring the pHi of shallow water corals was adapted for use with deep-sea corals for the first time. pHi was independent from the seawater treatment and ranged from 7.67 – 8.30. Respiration rate was not influenced by the reduced seawater pH tested here. Respiration rates were highly variable, ranging from 0.065 to 1.756 μg O2 g-1 protein h-1 and pHi ranged from 7.67 – 8.30. Yearly growth rates were also variable, ranging from 0.53 to 3.068 mm year-1, and again showed no detectable difference between the treatment and control colonies. However, a loss in the colouration of coral skeletons was observed in the treatment group and was attributed to a loss of tissue. This could indicate a reallocation of energy, allowing for the maintenance of those other physiological parameters measured here (e.g. growth and respiration rates). If this is indeed occurring, it would be consistent with the idea of phenotypic plasticity, where corals can alternate between soft-bodied and fossilizing forms, allowing them to survive past periods of environmental stress.   This research is an important first step towards understanding the sensitivity of deep-sea corals to OA and the potential for acclimation, and suggests that in many respects, S. variabilis might not be susceptible to end-of-century projections of OA. Nevertheless, the observed tissue loss is interesting and warrants further investigation to assess its long-term implications. Furthermore, the impacts of greater levels of OA, and the interactive effects of other ecological parameters such as food availability, need to be tested.</p>

scholarly journals Dichotomy between regulation of coral bacterial communities and calcification physiology under ocean acidification conditions

2021 ◽  
Author(s):  
A. Shore ◽  
R. D. Day ◽  
J. A. Stewart ◽  
C.A. Burge
Keyword(s):  
Ocean Acidification ◽  
Bacterial Communities ◽  
16S Rrna Gene Sequencing ◽  
Ph Gradient ◽  
Rrna Gene ◽  
Seawater Ph ◽  
Coral Health ◽  
And Function ◽  
The Impact

Ocean acidification (OA) threatens the growth and function of coral reef ecosystems. A key component to coral health is the microbiome, but little is known about the impact of OA on coral microbiomes. A submarine CO2 vent at Maug Island in the Northern Marianas Islands provides a natural pH gradient to investigate coral responses to long-term OA conditions. Three coral species (Pocillopora eydouxi, Porites lobata, and Porites rus) were sampled from three sites where mean seawater pH is 8.04, 7.98, and 7.94. We characterized coral bacterial communities (using 16S rRNA gene sequencing) and determined pH of the extracellular calcifying fluid (ECF) (using skeletal boron isotopes) across the seawater pH gradient. Bacterial communities of both Porites species stabilized (decreases in community dispersion) with decreased seawater pH, coupled with large increases in the abundance of Endozoicomonas, an endosymbiont. P. lobata experienced a significant decrease in ECF pH near the vent, whereas P. rus experienced a trending decrease in ECF pH near the vent. By contrast, Pocillopora exhibited bacterial community destabilization (increases in community dispersion), with significant decreases in Endozoicomonas abundance, while its ECF pH remained unchanged across the pH gradient. Our study shows that OA has multiple consequences on Endozoicomonas abundance and suggests that Endozoicomonas abundance may be an indicator of coral response to OA. We reveal an interesting dichotomy between two facets of coral physiology (regulation of bacterial communities and regulation of calcification), highlighting the importance of multidisciplinary approaches to understanding coral health and function in a changing ocean. IMPORTANCE Ocean acidification (OA) is a consequence of anthropogenic CO2 emissions that is negatively impacting marine ecosystems such as coral reefs. OA affects many aspects of coral physiology, including growth (i.e. calcification) and disrupting associated bacterial communities. Coral-associated bacteria are important for host health, but it remains unclear how coral-associated bacterial communities will respond to future OA conditions. We document changes in coral-associated bacterial communities and changes to calcification physiology with long-term exposure to decreases in seawater pH that are environmentally relevant under mid-range IPCC emission scenarios (0.1 pH units). We also find species-specific responses that may reflect different responses to long-term OA. In Pocillopora, calcification physiology was highly regulated despite changing seawater conditions. In Porites spp., changes in bacterial communities do not reflect a breakdown of coral-bacterial symbiosis. Insights into calcification and host-microbe interactions are critical to predicting the health and function of different coral taxa to future OA conditions.

scholarly journals Distinct eGFR trajectories are associated with risk of myocardial infarction in people with diabetes or pre-diabetes

2020 ◽  
Author(s):  
Yingting Zuo ◽  
Anxin Wang ◽  
Shuohua Chen ◽  
Xue Tian ◽  
Shouling Wu ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Proportional Hazards ◽  
Exposure Period ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Models ◽  
Hazard Ratios ◽  
Increased Risk ◽  
And Control ◽  
Incident Cases

Abstract Background The relationship between estimated glomerular filtration rate (eGFR) trajectories and myocardial infarction (MI) remains unclear in people with diabetes or prediabetes. We aimed to identify common eGFR trajectories in people with diabetes or prediabetes and to examine their association with MI risk. Methods The data of this analysis was derived from the Kailuan study, which was a prospective community-based cohort study. The eGFR trajectories of 24,723 participants from year 2006 to 2012 were generated by latent mixture modeling. Incident cases of MI occurred during 2012 to 2017, confirmed by review of medical records. Cox proportional hazards models were used to calculate hazard ratios (HR) and their 95% confidence intervals (CIs) for the subsequent risk of MI of different eGFR trajectories. Results We identified 5 distinct eGFR trajectories, and named them as low-stable (9.4%), moderate-stable (31.4%), moderate-increasing (29.5%), high-decreasing (13.9%) and high-stable (15.8%) according to their range and pattern. During a mean follow-up of 4.61 years, there were a total of 235 incident MI. Although, the high-decreasing group had similar eGFR levels with the moderate-stable group at last exposure period, the risk was much higher (adjusted HR, 3.43; 95%CI, 1.56–7.54 versus adjusted HR, 2.82; 95%CI, 1.34–5.95). Notably, the moderate-increasing group had reached to the normal range, still had a significantly increased risk (adjusted HR, 2.55; 95%CI, 1.21–5.39). Conclusions eGFR trajectories were associated with MI risk in people with diabetes or prediabetes. Emphasis should be placed on early and long-term detection and control of eGFR decreases to further reduce MI risk.

Deep Sea Observatories

1999 ◽  
Vol 33 (4) ◽  
pp. 41-48 ◽  
Author(s):  
Andrew M. Clark
Keyword(s):  
Real Time ◽  
Deep Sea ◽  
Sea Floor ◽  
Enabling Technologies ◽  
And Control

A survey of some deep-sea observatories that have either been deployed or have been developed is provided. The enabling technologies that facilitate the powering, comrrtartd and control and the transmission of data back to shore is discussed. To facilitate this discussion, examples of a number of observatories are categorized as “Wired to Shore”, “Wired to Surface” or “Wireless”. Among those observatories discussed are Japan’s Hatsushimu Real Time Long-term Deep Sea Floor Observatory, the Hawaii Undersea Geo-Observatory (HUGO), the Hawaii 2 Observatory (H2O), Ocean Net, the Geophysical and Oceanographic Station for Abyssal Research (GEOSTAR) and the NEPTUNE Project. Some relative advantages of each approach are discussed as regards cost, technical and logistical considerations.

scholarly journals Scleractinian corals incorporate microplastic particles: identification from a laboratory study

2021 ◽  
Author(s):  
Florian Hierl ◽  
Henry C. Wu ◽  
Hildegard Westphal
Keyword(s):  
Deep Sea ◽  
Skeletal Growth ◽  
Tropical Species ◽  
Pollution Effects ◽  
Food Items ◽  
Physiological Processes ◽  
Hermatypic Corals ◽  
Long Term Consequences ◽  
High Concentrations

AbstractMicroplastics have been detected on beaches and in the ocean from surface habitats to the deep-sea. Microplastics can be mistaken for food items by marine organisms, posing a potential risk for bioaccumulation and biomagnification in the food chain. Our understanding of microplastic pollution effects on ecosystem and physiological processes of coral reefs is still limited. This study contributes to the understanding of effects of microplastic pollution on skeletal precipitation of hermatypic corals. In a five month aquarium-based experiment, specimens of four tropical species were temporarily exposed to high concentrations (ca. 0.5 g L-1) of polyethylene terephthalate (PET) microplastic particles (< 500 μm). The coral specimens all survived this treatment and show skeletal growth. The skeletal material produced during the experiment, however, incorporated plastic particles and plastic fibres in the aragonitic structure. Long-term consequences of such inclusions on skeletal properties such as stability are yet unknown.

scholarly journals Coral calcification mechanisms facilitate adaptive responses to ocean acidification

2017 ◽  
Vol 284 (1868) ◽  
pp. 20172117 ◽  
Author(s):  
Verena Schoepf ◽  
Christopher P. Jury ◽  
Robert J. Toonen ◽  
Malcolm T. McCulloch
Keyword(s):  
Ocean Acidification ◽  
Inorganic Carbon ◽  
Coral Species ◽  
Dissolved Inorganic Carbon ◽  
Adaptive Responses ◽  
Natural Gradient ◽  
Coral Calcification ◽  
Seawater Ph ◽  
Two Temperatures

Ocean acidification (OA) is a pressing threat to reef-building corals, but it remains poorly understood how coral calcification is inhibited by OA and whether corals could acclimatize and/or adapt to OA. Using a novel geochemical approach, we reconstructed the carbonate chemistry of the calcifying fluid in two coral species using both a pH and dissolved inorganic carbon (DIC) proxy (δ 11 B and B/Ca, respectively). To address the potential for adaptive responses, both species were collected from two sites spanning a natural gradient in seawater pH and temperature, and then subjected to three pH T levels (8.04, 7.88, 7.71) crossed by two temperatures (control, +1.5°C) for 14 weeks. Corals from the site with naturally lower seawater pH calcified faster and maintained growth better under simulated OA than corals from the higher-pH site. This ability was consistently linked to higher pH yet lower DIC values in the calcifying fluid, suggesting that these differences are the result of long-term acclimatization and/or local adaptation to naturally lower seawater pH. Nevertheless, all corals elevated both pH and DIC significantly over seawater values, even under OA. This implies that high pH upregulation combined with moderate levels of DIC upregulation promote resistance and adaptive responses of coral calcification to OA.

scholarly journals A unique temperate rocky coastal hydrothermal vent system (Whakaari–White Island, Bay of Plenty, New Zealand): constraints for ocean acidification studies

2020 ◽  
Vol 71 (3) ◽  
pp. 321 ◽  
Author(s):  
R. Zitoun ◽  
S. D. Connell ◽  
C. E. Cornwall ◽  
K. I. Currie ◽  
K. Fabricius ◽  
...  
Keyword(s):  
New Zealand ◽  
Ocean Acidification ◽  
Preliminary Investigation ◽  
Nutrient Concentrations ◽  
Seawater Ph ◽  
Combination Of Methods ◽  
And Control ◽  
Inorganic Ligands ◽  
White Island

In situ effects of ocean acidification are increasingly studied at submarine CO2 vents. Here we present a preliminary investigation into the water chemistry and biology of cool temperate CO2 vents near Whakaari–White Island, New Zealand. Water samples were collected inside three vent shafts, within vents at a distance of 2m from the shaft and at control sites. Vent samples contained both seawater pH on the total scale (pHT) and carbonate saturation states that were severely reduced, creating conditions as predicted for beyond the year 2100. Vent samples showed lower salinities, higher temperatures and greater nutrient concentrations. Sulfide levels were elevated and mercury levels were at concentrations considered toxic at all vent and control sites, but stable organic and inorganic ligands were present, as deduced from Cu speciation data, potentially mediating harmful effects on local organisms. The biological investigations focused on phytoplankton, zooplankton and macroalgae. Interestingly, we found lower abundances but higher diversity of phytoplankton and zooplankton at sites in the direct vicinity of Whakaari. Follow-up studies will need a combination of methods and approaches to attribute observations to specific drivers. The Whakaari vents represent a unique ecosystem with considerable biogeochemical complexity, which, like many other vent systems globally, require care in their use as a model of ‘future oceans’.

Suppressed, but Not Forgotten

2011 ◽  
Vol 70 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Beat Meier ◽  
Anja König ◽  
Samuel Parak ◽  
Katharina Henke
Keyword(s):  
Memory Trace ◽  
Thought Suppression ◽  
Test Phase ◽  
Indirect Test ◽  
Final Test ◽  
Test Experiment ◽  
And Control ◽  
Cue Words ◽  
The Impact

This study investigates the impact of thought suppression over a 1-week interval. In two experiments with 80 university students each, we used the think/no-think paradigm in which participants initially learn a list of word pairs (cue-target associations). Then they were presented with some of the cue words again and should either respond with the target word or avoid thinking about it. In the final test phase, their memory for the initially learned cue-target pairs was tested. In Experiment 1, type of memory test was manipulated (i.e., direct vs. indirect). In Experiment 2, type of no-think instructions was manipulated (i.e., suppress vs. substitute). Overall, our results showed poorer memory for no-think and control items compared to think items across all experiments and conditions. Critically, however, more no-think than control items were remembered after the 1-week interval in the direct, but not in the indirect test (Experiment 1) and with thought suppression, but not thought substitution instructions (Experiment 2). We suggest that during thought suppression a brief reactivation of the learned association may lead to reconsolidation of the memory trace and hence to better retrieval of suppressed than control items in the long term.

Sign in / Sign up

Export Citation Format

Share Document