scholarly journals In situ Skeletal Growth Rates of the Solitary Cold-Water Coral Tethocyathus endesa From the Chilean Fjord Region

2021 ◽  
Vol 8 ◽  
Author(s):  
Susann Rossbach ◽  
Felix Ivo Rossbach ◽  
Verena Häussermann ◽  
Günter Försterra ◽  
Jürgen Laudien
Keyword(s):  
Growth Rates ◽  
Environmental Conditions ◽  
Cold Water ◽  
Euphotic Zone ◽  
Skeletal Growth ◽  
Lophelia Pertusa ◽  
Seawater Chemistry ◽  
Skeletal Mass ◽  
Wide Range

Cold-water corals (CWC) can be found throughout a wide range of latitudes (79°N–78°S). Since they lack the photosymbiosis known for most of their tropical counterparts, they may thrive below the euphotic zone. Consequently, their growth predominantly depends on the prevalent environmental conditions, such as general food availability, seawater chemistry, currents, and temperature. Most CWC communities live in regions that will face CaCO3 undersaturation by the end of the century and are thus predicted to be threatened by ocean acidification (OA). This scenario is especially true for species inhabiting the Chilean fjord system, where present-day carbonate water chemistry already reaches values predicted for the end of the century. To understand the effect of the prevailing environmental conditions on the biomineralization of the CWC Tethocyathus endesa, a solitary scleractinian widely distributed in the Chilean Comau Fjord, a 12-month in situ experiment was conducted. The in situ skeletal growth of the test corals was assessed at two sites using the buoyant weight method. Sites were chosen to cover the naturally present carbonate chemistry gradient, with pH levels ranging between 7.90 ± 0.01 (mean ± SD) and 7.70 ± 0.02, and an aragonite saturation (Ωarag) between 1.47 ± 0.03 and 0.98 ± 0.05. The findings of this study provide one of the first in situ growth assessments of a solitary CWC species, with a skeletal mass increase of 46 ± 28 mg per year and individual, at a rate of 0.03 ± 0.02% day. They also indicate that, although the local seawater chemistry can be assumed to be unfavorable for calcification, growth rates of T. endesa are comparable to other cold-water scleractinians in less corrosive waters (e.g., Lophelia pertusa in the Mediterranean Sea).

Diversity of the sponge fauna associated with white coral banks from two Sardinian canyons (Mediterranean Sea)

2019 ◽  
Vol 99 (8) ◽  
pp. 1735-1751 ◽  
Author(s):  
M. Bertolino ◽  
S. Ricci ◽  
S. Canese ◽  
A. Cau ◽  
G. Bavestrello ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Cold Water ◽  
Three Dimensional ◽  
Western Mediterranean ◽  
Tyrrhenian Sea ◽  
Lophelia Pertusa ◽  
Wide Range ◽  
Santa Maria

AbstractThe three-dimensional coral scaffolds formed by the skeletons of the cold-water corals Madrepora oculata and Lophelia pertusa represent an important deep-sea hard substratum and create an optimal shelter for a rich associated fauna in which the contribution of Porifera has still not been fully considered. The taxonomic analysis of sponges collected from two Sardinian canyons (Nora and Coda Cavallo, 256–408 m) and associated with the dead coral matrix resulted in 28 species, including new records for the Mediterranean Sea, Italian fauna or Central Tyrrhenian Sea. In addition, for many species this is the first finding associated with the coral framework or the first documentation of the in situ morphology. The taxonomic comparison with sponge assemblages associated with coral frameworks from Santa Maria di Leuca, Strait of Sicily and Bari Canyon, gave the opportunity to evaluate the similarities among geographically separated banks. Overall, the percentage of exclusive species (recorded only in one site), is very high (81%) and only one species is shared by all four sites, suggesting a low connectivity among the sponge communities. The percentage of shared species is higher for the Maltese community, supporting the role of the Sicily Channel as a crossroads between the communities of the eastern and western Mediterranean basins. Here, 55% of the sponges associated to the coral framework are also reported in shallow-water coralligenous assemblages, indicating a high bathymetric connectivity as well as an ecological plasticity allowing these species to occupy a wide range of small, dark refuges.

scholarly journals In situ growth and bioerosion rates of Lophelia pertusa in a Norwegian fjord and open shelf cold-water coral habitat

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7586 ◽  
Author(s):  
Janina V. Büscher ◽  
Max Wisshak ◽  
Armin U. Form ◽  
Jürgen Titschack ◽  
Kerstin Nachtigall ◽  
...  
Keyword(s):  
Coral Reef ◽  
Growth Rates ◽  
Environmental Changes ◽  
Cold Water ◽  
Lophelia Pertusa ◽  
Reef Growth ◽  
Dead Coral ◽  
Open Shelf ◽  
Water Coral

Coral reef resilience depends on the balance between carbonate precipitation, leading to reef growth, and carbonate degradation, for example, through bioerosion. Changes in environmental conditions are likely to affect the two processes differently, thereby shifting the balance between reef growth and degradation. In cold-water corals estimates of accretion-erosion processes in their natural habitat are scarce and solely live coral growth rates were studied with regard to future environmental changes in the laboratory so far, limiting our ability to assess the potential of cold-water coral reef ecosystems to cope with environmental changes. In the present study, growth rates of the two predominant colour morphotypes of live Lophelia pertusa as well as bioerosion rates of dead coral framework were assessed in different environmental settings in Norwegian cold-water coral reefs in a 1-year in situ experiment. Net growth (in weight gain and linear extension) of live L. pertusa was in the lower range of previous estimates and did not significantly differ between inshore (fjord) and offshore (open shelf) habitats. However, slightly higher net growth rates were obtained inshore. Bioerosion rates were significantly higher on-reef in the fjord compared to off-reef deployments in- and offshore. Besides, on-reef coral fragments yielded a broader range of individual growth and bioerosion rates, indicating higher turnover in live reef structures than off-reef with regard to accretion–bioerosion processes. Moreover, if the higher variation in growth rates represents a greater variance in (genetic) adaptations to natural environmental variability in the fjord, inshore reefs could possibly benefit under future ocean change compared to offshore reefs. Although not significantly different due to high variances between replicates, growth rates of orange branches were consistently higher at all sites, while mortality was statistically significantly lower, potentially indicating higher stress-resistance than the less pigmented white phenotype. Comparing the here measured rates of net accretion of live corals (regardless of colour morphotype) with net erosion of dead coral framework gives a first estimate of the dimensions of both processes in natural cold-water coral habitats, indicating that calcium carbonate loss through bioerosion amounts to one fifth to one sixth of the production rates by coral calcification (disregarding accretion processes of other organisms and proportion of live and dead coral framework in a reef). With regard to likely accelerating bioerosion and diminishing growth rates of corals under ocean acidification, the balance of reef accretion and degradation may be shifted towards higher biogenic dissolution in the future.

scholarly journals <sup>210</sup>Pb-<sup>226</sup>Ra chronology reveals rapid growth rate of <i>Madrepora oculata</i> and <i>Lophelia pertusa</i> on world's largest cold-water coral reef

2012 ◽  
Vol 9 (3) ◽  
pp. 1253-1265 ◽  
Author(s):  
P. Sabatier ◽  
J.-L. Reyss ◽  
J. M. Hall-Spencer ◽  
C. Colin ◽  
N. Frank ◽  
...  
Keyword(s):  
Growth Rate ◽  
Coral Reef ◽  
Metal Oxides ◽  
Growth Rates ◽  
Cold Water ◽  
Age And Growth ◽  
Lophelia Pertusa ◽  
Fe Oxide ◽  
Oxide Contamination ◽  
Water Coral

Abstract. Here we show the use of the 210Pb-226Ra excess method to determine the growth rate of two corals from the world's largest known cold-water coral reef, Røst Reef, north of the Arctic circle off Norway. Colonies of each of the two species that build the reef, Lophelia pertusa and Madrepora oculata, were collected alive at 350 m depth using a submersible. Pb and Ra isotopes were measured along the major growth axis of both specimens using low level alpha and gamma spectrometry and trace element compositions were studied. 210Pb and 226Ra differ in the way they are incorporated into coral skeletons. Hence, to assess growth rates, we considered the exponential decrease of initially incorporated 210Pb, as well as the increase in 210Pb from the decay of 226Ra and contamination with 210Pb associated with Mn-Fe coatings that we were unable to remove completely from the oldest parts of the skeletons. 226Ra activity was similar in both coral species, so, assuming constant uptake of 210Pb through time, we used the 210Pb-226Ra chronology to calculate growth rates. The 45.5 cm long branch of M. oculata was 31 yr with an average linear growth rate of 14.4 ± 1.1 mm yr−1 (2.6 polyps per year). Despite cleaning, a correction for Mn-Fe oxide contamination was required for the oldest part of the colony; this correction corroborated our radiocarbon date of 40 yr and a mean growth rate of 2 polyps yr−1. This rate is similar to the one obtained in aquarium experiments under optimal growth conditions. For the 80 cm-long L. pertusa colony, metal-oxide contamination remained in both the middle and basal part of the coral skeleton despite cleaning, inhibiting similar age and growth rate estimates. The youngest part of the colony was free of metal oxides and this 15 cm section had an estimated a growth rate of 8 mm yr−1, with high uncertainty (~1 polyp every two to three years). We are less certain of this 210Pb growth rate estimate which is within the lowermost ranges of previous growth rate estimates. We show that 210Pb-226Ra dating can be successfully applied to determine the age and growth rate of framework-forming cold-water corals if Mn-Fe oxide deposits can be removed. Where metal oxides can be removed, large M. oculata and L. pertusa skeletons provide archives for studies of intermediate water masses with an up to annual time resolution and spanning over many decades.

In Situ Synchrotron X-ray Absorption Experiments and Modelling of the Growth Rates of Electrochemically Deposited ZnO Nanostructures

2007 ◽  
Vol 1017 ◽  
Author(s):  
Bridget Ingham ◽  
Benoit N. Illy ◽  
Jade R. Mackay ◽  
Stephen P. White ◽  
Shaun C. Hendy ◽  
...  
Keyword(s):  
Growth Rates ◽  
High Resolution Electron Microscopy ◽  
Ex Situ ◽  
X Ray ◽  
Deposition Parameters ◽  
Wide Range ◽  
Electrochemically Deposited ◽  
Electrochemical Current ◽  
X Ray Absorption

AbstractZnO is known to produce a wide variety of nanostructures that have enormous scope for optoelectronic applications. Using an aqueous electrochemical deposition technique, we are able to tightly control a wide range of deposition parameters (Zn2+ concentration, temperature, potential, time) and hence the resulting deposit morphology. By simultaneously conducting synchrotron x-ray absorption spectroscopy (XAS) experiments during the deposition, we are able to directly monitor the growth rates of the nanostructures, as well as providing direct chemical speciation of the films. In situ experiments such as these are critical to understanding the nucleation and growth of such nanostructures.Recent results from in situ XAS synchrotron experiments demonstrate the growth rates as a function of potential and Zn2+ concentration. These are compared with the electrochemical current density recorded during the deposition, and the final morphology revealed through ex situ high resolution electron microscopy. The results are indicative of two distinct growth regimes, and simultaneous changes in the morphology are observed.These experiments are complemented by modelling the growth of the rods in the transport-limited case, using the Nernst-Planck equations in 2 dimensions, to yield the growth rate of the volume, length, and radius as a function of time.

Experimental comparison of skeletal growth rates in the cold-water coral Madrepora oculata Linnaeus, 1758 and three tropical scleractinian corals

2011 ◽  
Vol 405 (1-2) ◽  
pp. 1-5 ◽  
Author(s):  
Covadonga Orejas ◽  
Christine Ferrier-Pagès ◽  
Stéphanie Reynaud ◽  
Georgios Tsounis ◽  
Denis Allemand ◽  
...  
Keyword(s):  
Growth Rates ◽  
Cold Water ◽  
Scleractinian Corals ◽  
Skeletal Growth ◽  
Experimental Comparison ◽  
Water Coral

scholarly journals Tissue-Associated “Candidatus Mycoplasma corallicola” and Filamentous Bacteria on the Cold-Water Coral Lophelia pertusa (Scleractinia)

2008 ◽  
Vol 75 (5) ◽  
pp. 1437-1444 ◽  
Author(s):  
Sven C. Neulinger ◽  
Andrea Gärtner ◽  
Johanna Järnegren ◽  
Martin Ludvigsen ◽  
Karin Lochte ◽  
...  
Keyword(s):  
Cold Water ◽  
Gastric Fluid ◽  
Lophelia Pertusa ◽  
Coral Mucus ◽  
Key Species ◽  
Bona Fide ◽  
Catalyzed Reporter Deposition ◽  
Bacterial Assemblages ◽  
Water Coral

ABSTRACT The cold-water coral Lophelia pertusa (Scleractinia, Caryophylliidae) is a key species in the formation of cold-water reefs, which are among the most diverse deep-sea ecosystems. It occurs in two color varieties: white and red. Bacterial communities associated with Lophelia have been investigated in recent years, but the role of the associated bacteria remains largely obscure. This study uses catalyzed reporter deposition fluorescence in situ hybridization to detect the in situ location of specific bacterial groups on coral specimens from the Trondheimsfjord (Norway). Two tissue-associated groups were identified: (i) bacteria on the host's tentacle ectoderm, “Candidatus Mycoplasma corallicola,” are flasklike, pointed cells and (ii) endoderm-associated bona fide TM7 bacteria form long filaments in the gastral cavity. These tissue-bound bacteria were found in all coral specimens from the Trondheimsfjord, indicating a closer relationship with the coral compared to bacterial assemblages present in coral mucus and gastric fluid.

scholarly journals The microbiome as a biosensor: functional profiles elucidate hidden stress in hosts

2019 ◽  
Author(s):  
Avihai Zolti ◽  
Stefan J. Green ◽  
Noa Sela ◽  
Yitzhak Hadar ◽  
Dror Minz
Keyword(s):  
Microbial Communities ◽  
Environmental Conditions ◽  
Transcriptional Analysis ◽  
Treated Wastewater ◽  
Proof Of Concept ◽  
Plant Host ◽  
Soil System ◽  
General Stress ◽  
Wide Range

AbstractMicrobial communities are highly responsive to environmental cues, and both their structure and activity can be altered in response to changing conditions. We hypothesized that host-associated microbial communities, particularly those colonizing host surfaces, can serve as in situ sensors to reveal environmental conditions experienced by both microorganisms and the host. For a proof-of-concept, we studied a model plant-soil system and employed a non-deterministic gene-centric approach. A holistic analysis was performed using plants of two species and irrigation with water of low quality to induce host stress. Our analyses examined the genetic potential (DNA) and gene expression patterns (RNA) of plant-associated microbial communities, as well as transcriptional profiling of host plants. Transcriptional analysis of plants irrigated with treated wastewater revealed significant enrichment of general stress-associated root transcripts relative to plants irrigated with fresh water. Metagenomic analysis of root-associated microbial communities in treated wastewater-irrigated plants, however, revealed enrichment of more specific stress-associated genes relating to high levels of salt, high pH and lower levels of oxygen. Meta-analysis of these differentially abundant genes obtained from other metagenome studies provided evidence of the link between environmental factors such as pH and oxygen and these genes. Analysis of microbial transcriptional response demonstrated that enriched gene content was actively expressed, which implies contemporary response to elevated levels of pH and salt. We demonstrate here that microbial profiling can elucidate stress signals that cannot be observed even through interrogation of host transcriptome, leading to an alternate mechanism for evaluating in situ conditions experienced by host organisms.Significance StatementThis study examines the potential for microbial communities to provide insight into stresses experienced by their eukaryotic host organisms, through profiling of metagenomes and metatranscriptomes. Our study uses plant host-associated microorganisms as an in vivo and in situ microsensor to identify environmental stresses experienced by the microbial community and by the plant. Transcriptionally active host-associated microbial communities are responsive in a highly specific manner to environmental conditions. Conversely, host transcriptome sequencing provides only a very general stress response. This study is a proof-of-concept for the use of microbial communities as microsensors, with a great potential for interrogation of a wide range of host systems.

Sign in / Sign up

Export Citation Format

Share Document