To see the other types of publications on this topic, follow the link: Coral samples.
Journal articles on the topic 'Coral samples'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Coral samples.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Lema, Kimberley A., Bette L. Willis, and David G. Bourne. "Corals Form Characteristic Associations with Symbiotic Nitrogen-Fixing Bacteria." Applied and Environmental Microbiology 78, no. 9 (February 17, 2012): 3136–44. http://dx.doi.org/10.1128/aem.07800-11.
Full textAbstract:
ABSTRACTThe complex symbiotic relationship between corals and their dinoflagellate partnerSymbiodiniumis believed to be sustained through close associations with mutualistic bacterial communities, though little is known about coral associations with bacterial groups able to fix nitrogen (diazotrophs). In this study, we investigated the diversity of diazotrophic bacterial communities associated with three common coral species (Acropora millepora,Acropora muricata, andPocillopora damicormis) from three midshelf locations of the Great Barrier Reef (GBR) by profiling the conserved subunit of thenifHgene, which encodes the dinitrogenase iron protein. Comparisons of diazotrophic community diversity among coral tissue and mucus microenvironments and the surrounding seawater revealed that corals harbor diversenifHphylotypes that differ between tissue and mucus microhabitats. Coral mucusnifHsequences displayed high heterogeneity, and many bacterial groups overlapped with those found in seawater. Moreover, coral mucus diazotrophs were specific neither to coral species nor to reef location, reflecting the ephemeral nature of coral mucus. In contrast, the dominant diazotrophic bacteria in tissue samples differed among coral species, with differences remaining consistent at all three reefs, indicating that coral-diazotroph associations are species specific. Notably, dominant diazotrophs for all coral species were closely related to the bacterial group rhizobia, which represented 71% of the total sequences retrieved from tissue samples. The species specificity of coral-diazotroph associations further supports the coral holobiont model that bacterial groups associated with corals are conserved. Our results suggest that, as in terrestrial plants, rhizobia have developed a mutualistic relationship with corals and may contribute fixed nitrogen toSymbiodinium.
2
Andersson, Erik, Rusty Day, Julie Loewenstein, Cheryl Woodley, and Tracey Schock. "Evaluation of Sample Preparation Methods for the Analysis of Reef-Building Corals Using 1H-NMR-Based Metabolomics." Metabolites 9, no. 2 (February 13, 2019): 32. http://dx.doi.org/10.3390/metabo9020032.
Full textAbstract:
The field of metabolomics generally lacks standardized methods for the preparation of samples prior to analysis. This is especially true for metabolomics of reef-building corals, where the handful of studies that were published employ a range of sample preparation protocols. The utilization of metabolomics may prove essential in understanding coral biology in the face of increasing environmental threats, and an optimized method for preparing coral samples for metabolomics analysis would aid this cause. The current study evaluates three important steps during sample processing of stony corals: (i) metabolite extraction, (ii) metabolism preservation, and (iii) subsampling. Results indicate that a modified Bligh and Dyer extraction is more reproducible across multiple coral species compared to methyl tert-butyl ether and methanol extractions, while a methanol extraction is superior for feature detection. Additionally, few differences were detected between spectra from frozen or lyophilized coral samples. Finally, extraction of entire coral nubbins increased feature detection, but decreased throughput and was more susceptible to subsampling error compared to a novel tissue powder subsampling method. Overall, we recommend the use of a modified Bligh and Dyer extraction, lyophilized samples, and the analysis of brushed tissue powder for the preparation of reef-building coral samples for 1H NMR metabolomics.
3
Briggs, Amy A., Anya L. Brown, and Craig W. Osenberg. "Local versus site-level effects of algae on coral microbial communities." Royal Society Open Science 8, no. 9 (September 2021): 210035. http://dx.doi.org/10.1098/rsos.210035.
Full textAbstract:
Microbes influence ecological processes, including the dynamics and health of macro-organisms and their interactions with other species. In coral reefs, microbes mediate negative effects of algae on corals when corals are in contact with algae. However, it is unknown whether these effects extend to larger spatial scales, such as at sites with high algal densities. We investigated how local algal contact and site-level macroalgal cover influenced coral microbial communities in a field study at two islands in French Polynesia, Mo'orea and Mangareva. At 5 sites at each island, we sampled prokaryotic microbial communities (microbiomes) associated with corals, macroalgae, turf algae and water, with coral samples taken from individuals that were isolated from or in contact with turf or macroalgae. Algal contact and macroalgal cover had antagonistic effects on coral microbiome alpha and beta diversity. Additionally, coral microbiomes shifted and became more similar to macroalgal microbiomes at sites with high macroalgal cover and with algal contact, although the microbial taxa that changed varied by island. Our results indicate that coral microbiomes can be affected by algae outside of the coral's immediate vicinity, and local- and site-level effects of algae can obscure each other's effects when both scales are not considered.
4
Beman, J. Michael, Kathryn J. Roberts, Linda Wegley, Forest Rohwer, and Christopher A. Francis. "Distribution and Diversity of Archaeal Ammonia Monooxygenase Genes Associated with Corals." Applied and Environmental Microbiology 73, no. 17 (June 22, 2007): 5642–47. http://dx.doi.org/10.1128/aem.00461-07.
Full textAbstract:
ABSTRACT Corals are known to harbor diverse microbial communities of Bacteria and Archaea, yet the ecological role of these microorganisms remains largely unknown. Here we report putative ammonia monooxygenase subunit A (amoA) genes of archaeal origin associated with corals. Multiple DNA samples drawn from nine coral species and four different reef locations were PCR screened for archaeal and bacterial amoA genes, and archaeal amoA gene sequences were obtained from five different species of coral collected in Bocas del Toro, Panama. The 210 coral-associated archaeal amoA sequences recovered in this study were broadly distributed phylogenetically, with most only distantly related to previously reported sequences from coastal/estuarine sediments and oceanic water columns. In contrast, the bacterial amoA gene could not be amplified from any of these samples. These results offer further evidence for the widespread presence of the archaeal amoA gene in marine ecosystems, including coral reefs.
5
Esquivel-Garrote, Octavio, and Álvaro Morales-Ramírez. "Community structure of coral reef zooplankton in Isla del Coco National Park, a natural World Heritage site in the Eastern Tropical Pacific." Revista de Biología Tropical 68, S1 (March 24, 2020): S248—S260. http://dx.doi.org/10.15517/rbt.v68is1.41188.
Full textAbstract:
Introduction: Zooplankton is a major link between primary producers and the following trophic levels, and in coral reefs they represent an energy source for corals and involve complex assemblies integrating a wide variety of species form different functional groups. Objective: To define interannual changes in zooplankton assemblies in coral reefs of Isla del Coco. Methods: Three coral reefs system were sampled. Two or three samples were taken by surface horizontal trawls in each coral reef from 2009 to 2012, using conical zooplankton nets of 200 and 500 µm mesh sizes at different times of the day. Physical and chemical variables were measured before zooplankton sampling. Results: We identified 24 taxonomic groups of macrozooplankton and 22 of mesozooplankton. Copepods were the most abundant taxa (87.1%) of the total abundance of mesozooplankton and macrozooplakton (58.9%); however, chaetognaths (35.6%) exceeded copepods (35.4%) in abundance in macrozooplankton samples during 2011. Mesozooplankton samples showed higher abundance (68753.2±9123.2 ind m-3) and biomass (85.14±11.3 mg DW m-3) than macrozooplankton samples (4454.9±751.0 ind m-3, 22.8±3.8 mg DW m-3). The interannual macrozooplankton community structure did not change significantly (ANOVA, p=0.368), but did change for mesozooplankton (ANOVA, p=0.001). Variations in physical and chemical variables influenced the community structure for both meso and macrozooplankton, increasing or decreasing organism abundance. Conclusions: Coral reef zooplankton of Isla del Coco resembles that of other coral reefs under the influence of oceanic conditions, with a fauna formed mainly by calanoid copepods, chaetognaths and appendicularians, and depending on oceanographic conditions, the abundance of these groups can change.
6
Gong, Sanqiang, Xuejie Jin, Lijuan Ren, Yehui Tan, and Xiaomin Xia. "Unraveling Heterogeneity of Coral Microbiome Assemblages in Tropical and Subtropical Corals in the South China Sea." Microorganisms 8, no. 4 (April 21, 2020): 604. http://dx.doi.org/10.3390/microorganisms8040604.
Full textAbstract:
Understanding the coral microbiome is critical for predicting the fidelity of coral symbiosis with growing surface seawater temperature (SST). However, how the coral microbiome will respond to increasing SST is still understudied. Here, we compared the coral microbiome assemblages among 73 samples across six typical South China Sea coral species in two thermal regimes. The results revealed that the composition of microbiome varied across both coral species and thermal regimes, except for Porites lutea. The tropical coral microbiome displayed stronger heterogeneity and had a more un-compacted ecological network than subtropical coral microbiome. The coral microbiome was more strongly determined by environmental factors than host specificity. γ- (32%) and α-proteobacteria (19%), Bacteroidetes (14%), Firmicutes (14%), Actinobacteria (6%) and Cyanobacteria (2%) dominated the coral microbiome. Additionally, bacteria inferred to play potential roles in host nutrients metabolism, several keystone bacteria detected in human and plant rhizospheric microbiome were retrieved in explored corals. This study not only disentangles how different host taxa and microbiome interact and how such an interaction is affected by thermal regimes, but also identifies previously unrecognized keystone bacteria in corals, and also infers the community structure of coral microbiome will be changed from a compacted to an un-compacted network under elevated SST.
7
Lifshitz, Nofar, Lena Hazanov, Maoz Fine, and Oded Yarden. "Seasonal Variations in the Culturable Mycobiome of Acropora loripes along a Depth Gradient." Microorganisms 8, no. 8 (July 28, 2020): 1139. http://dx.doi.org/10.3390/microorganisms8081139.
Full textAbstract:
Coral associated fungi are widespread, highly diverse and are part and parcel of the coral holobiont. To study how environmental conditions prevailing near the coral-host may affect fungal diversity, the culturable (isolated on potato dextrose agar) mycobiome associated with Acropora loripes colonies was seasonally sampled along a depth gradient in the Gulf of Aqaba. Fragments were sampled from both apparently healthy coral colonies as well as those exhibiting observable lesions. Based on phylogenetic analysis of 197 fungal sequences, Ascomycota were the most prevalent (91.9%). The abundance of fungi increased with increasing water depth, where corals sampled at 25 m yielded up to 70% more fungal colony forming units (CFUs) than those isolated at 6 m. Fungal diversity at 25 m was also markedly higher, with over 2-fold more fungal families represented. Diversity was also higher in lesioned coral samples, when compared to apparently healthy colonies. In winter, concurrent with water column mixing and increased levels of available nutrients, at the shallow depths, Saccharomytacea and Sporidiobolacea were more prevalent, while in spring and fall Trichocomacea (overall, the most prevalent family isolated throughout this study) were the most abundant taxa isolated at these depths as well as at deeper sampling sites. Our results highlight the dynamic nature of the culturable coral mycobiome and its sensitivity to environmental conditions and coral health.
8
Dosoky, Muhammad Y., Fedekar F. Madkour, Mohamed I. Ahmed, and Mahmoud H. Hanafy. "Molecular Survey on Symbiodinium of Some Scleractinean Coral Spp. and a Fire Coral sp. along the Red Sea of Egypt." International Marine Science Journal 1, no. 1 (February 7, 2019): 17–27. http://dx.doi.org/10.14302/issn.2643-0282.imsj-18-2508.
Full textAbstract:
The present study introduce an overview on the cladal structure of Symbiodinium population associated with some species of scleractinean corals and fire coral in the Egyptian Red Sea coast and discuss the possible consequences of recent climate changes on coral reefs. Cladal structure of Symbiodinium populations associated with eight keystone species of scleractinean corals and one species of fire coral that collected along Egyptian Red Sea coast, during 2012-2013, had been resolved based on 18S nrDNA and ITS2 genetic markers. Only Symbiodinium subclades C1 and A1 were identified from all examined species. Symbiodinium C1 was the dominant subclade that associated with 61% of coral samples. Results revealed that the studied pocilloporid corals were associated with Symbiodinium C1 and/or A1 while acroporids were only associated with Symbiodinium C1. The present data also indicated that Symbiodinium C1 occurred at high densities than A1 or A1+C1 combination. Because of the relative thermal susceptibility of clades C and A, the current study addresses that the recent climate changes may derive dramatic changes on community structure of coral reefs at the Red Sea.
9
Fujii, Takanori, Yasuaki Tanaka, Koh Maki, Nobue Saotome, Naoko Morimoto, Atsushi Watanabe, and Toshihiro Miyajima. "Organic Carbon and Nitrogen Isoscapes of Reef Corals and Algal Symbionts: Relative Influences of Environmental Gradients and Heterotrophy." Microorganisms 8, no. 8 (August 11, 2020): 1221. http://dx.doi.org/10.3390/microorganisms8081221.
Full textAbstract:
The elemental (C/N) and stable isotopic (δ13C, δ15N) compositions and compound-specific δ15N values of amino acids (δ15NAA) were evaluated for coral holobionts as diagnostic tools to detect spatiotemporal environmental heterogeneity and its effects on coral health. Hermatypic coral samples of eight species were collected at 12 reef sites with differing levels of pollution stress. The C/N ratios, δ13C values, and δ15N values of coral tissues and endosymbiotic algae were determined for 193 coral holobionts, and the amino acid composition and δ15NAA values of selected samples were analyzed. δ15N values were influenced most by pollution stress, while C/N ratios and δ13C values depended most strongly on species. The results imply that δ13C and δ15N values are useful indicators for distinguishing the ecological niches of sympatric coral species based on microhabitat preference and resource selectivity. Using δ15NAA values, the trophic level (TL) of the examined coral samples was estimated to be 0.71 to 1.53, i.e., purely autotrophic to partially heterotrophic. Significant portions of the variation in bulk δ15N and δ13C values could be explained by the influence of heterotrophy. The TL of symbionts covaried with that of their hosts, implying that amino acids acquired through host heterotrophy are translocated to symbionts. Dependence on heterotrophy was stronger at polluted sites, indicating that the ecological role of corals changes in response to eutrophication.
10
Hartmann, Aaron C., Daniel Petras, Robert A. Quinn, Ivan Protsyuk, Frederick I. Archer, Emma Ransome, Gareth J. Williams, et al. "Meta-mass shift chemical profiling of metabolomes from coral reefs." Proceedings of the National Academy of Sciences 114, no. 44 (October 12, 2017): 11685–90. http://dx.doi.org/10.1073/pnas.1710248114.
Full textAbstract:
Untargeted metabolomics of environmental samples routinely detects thousands of small molecules, the vast majority of which cannot be identified. Meta-mass shift chemical (MeMSChem) profiling was developed to identify mass differences between related molecules using molecular networks. This approach illuminates metabolome-wide relationships between molecules and the putative chemical groups that differentiate them (e.g., H2, CH2, COCH2). MeMSChem profiling was used to analyze a publicly available metabolomic dataset of coral, algal, and fungal mat holobionts (i.e., the host and its associated microbes and viruses) sampled from some of Earth’s most remote and pristine coral reefs. Each type of holobiont had distinct mass shift profiles, even when the analysis was restricted to molecules found in all samples. This result suggests that holobionts modify the same molecules in different ways and offers insights into the generation of molecular diversity. Three genera of stony corals had distinct patterns of molecular relatedness despite their high degree of taxonomic relatedness. MeMSChem profiles also partially differentiated between individuals, suggesting that every coral reef holobiont is a potential source of novel chemical diversity.
11
Kellogg, Christina A., Steve W. Ross, and Sandra D. Brooke. "Bacterial community diversity of the deep-sea octocoralParamuricea placomus." PeerJ 4 (September 29, 2016): e2529. http://dx.doi.org/10.7717/peerj.2529.
Full textAbstract:
Compared to tropical corals, much less is known about deep-sea coral biology and ecology. Although the microbial communities of some deep-sea corals have been described, this is the first study to characterize the bacterial community associated with the deep-sea octocoral,Paramuricea placomus. Samples from five colonies ofP. placomuswere collected from Baltimore Canyon (379–382 m depth) in the Atlantic Ocean off the east coast of the United States of America. DNA was extracted from the coral samples and 16S rRNA gene amplicons were pyrosequenced using V4-V5 primers. Three samples sequenced deeply (>4,000 sequences each) and were further analyzed. The dominant microbial phylum was Proteobacteria, but other major phyla included Firmicutes and Planctomycetes. A conserved community of bacterial taxa held in common across the threeP. placomuscolonies was identified, comprising 68–90% of the total bacterial community depending on the coral individual. The bacterial community ofP. placomusdoes not appear to include the genusEndozoicomonas, which has been found previously to be the dominant bacterial associate in several temperate and tropical gorgonians. Inferred functionality suggests the possibility of nitrogen cycling by the core bacterial community.
12
Miller, Nicole, Paul Maneval, Carrie Manfrino, Thomas K. Frazer, and Julie L. Meyer. "Spatial distribution of microbial communities among colonies and genotypes in nursery-reared Acropora cervicornis." PeerJ 8 (August 26, 2020): e9635. http://dx.doi.org/10.7717/peerj.9635.
Full textAbstract:
Background The architecturally important coral species Acropora cervicornis and A. palmata were historically common in the Caribbean, but have declined precipitously since the early 1980s. Substantial resources are currently being dedicated to coral gardening and the subsequent outplanting of asexually reproduced colonies of Acropora, activities that provide abundant biomass for both restoration efforts and for experimental studies to better understand the ecology of these critically endangered coral species. Methods We characterized the bacterial and archaeal community composition of A. cervicornis corals in a Caribbean nursery to determine the heterogeneity of the microbiome within and among colonies. Samples were taken from three distinct locations (basal branch, intermediate branch, and branch tip) from colonies of three different coral genotypes. Results Overall, microbial community composition was similar among colonies due to high relative abundances of the Rickettsiales genus MD3-55 (Candidatus Aquarickettsia) in nearly all samples. While microbial communities were not different among locations within the same colony, they were significantly different between coral genotypes. These findings suggest that sampling from any one location on a coral host is likely to provide a representative sample of the microbial community for the entire colony. Our results also suggest that subtle differences in microbiome composition may be influenced by the coral host, where different coral genotypes host slightly different microbiomes. Finally, this study provides baseline data for future studies seeking to understand the microbiome of nursery-reared A. cervicornis and its roles in coral health, adaptability, and resilience.
13
Su, Hongfei, Zhenlun Xiao, Kefu Yu, Qinyu Huang, Guanghua Wang, Yinghui Wang, Jiayuan Liang, et al. "Diversity of cultivable protease-producing bacteria and their extracellular proteases associated to scleractinian corals." PeerJ 8 (May 6, 2020): e9055. http://dx.doi.org/10.7717/peerj.9055.
Full textAbstract:
Protease-producing bacteria play a vital role in degrading organic nitrogen in marine environments. However, the diversity of the bacteria and extracellular proteases has seldom been addressed, especially in communities of coral reefs. In this study, 136 extracellular protease-producing bacterial strains were isolated from seven genera of scleractinian corals from Luhuitou fringing reef, and their protease types were characterized. The massive coral had more cultivable protease-producing bacteria than branching or foliose corals. The abundance of cultivable protease-producing bacteria reached 106 CFU g−1 of coral. Phylogenetic analysis of 16S rRNA gene sequences revealed that the isolates were assigned to 24 genera, from which 20 corresponded to the phyla Firmicutes and Proteobacteria. Bacillus and Fictibacillus were retrieved from all coral samples. Moreover, Vibrio and Pseudovibrio were most prevalent in massive or foliose coral Platygyra and Montipora. In contrast, 11 genera were each identified in only one isolate. Nearly all the extracellular proteases from the bacteria were serine proteases or metalloproteases; 45.83% of isolates also released cysteine or aspartic proteases. These proteases had different hydrolytic ability against different substrates. This study represents a novel insight on the diversity of cultivable protease-producing bacteria and their extracellular proteases in scleractinian corals.
14
Kellogg, Christina A., John T. Lisle, and Julia P. Galkiewicz. "Culture-Independent Characterization of Bacterial Communities Associated with the Cold-Water Coral Lophelia pertusa in the Northeastern Gulf of Mexico." Applied and Environmental Microbiology 75, no. 8 (February 20, 2009): 2294–303. http://dx.doi.org/10.1128/aem.02357-08.
Full textAbstract:
ABSTRACT Bacteria are recognized as an important part of the total biology of shallow-water corals. Studies of shallow-water corals suggest that associated bacteria may benefit the corals by cycling carbon, fixing nitrogen, chelating iron, and producing antibiotics that protect the coral from other microbes. Cold-water or deep-sea corals have a fundamentally different ecology due to their adaptation to cold, dark, high-pressure environments and as such have novel microbiota. The goal of this study was to characterize the microbial associates of Lophelia pertusa in the northeastern Gulf of Mexico. This is the first study to collect the coral samples in individual insulated containers and to preserve coral samples at depth in an effort to minimize thermal shock and evaluate the effects of environmental gradients on the microbial diversity of samples. Molecular analysis of bacterial diversity showed a marked difference between the two study sites, Viosca Knoll 906/862 (VK906/862) and Viosca Knoll 826 (VK826). The bacterial communities from VK826 were dominated by a variety of unknown mycoplasmal members of the Tenericutes and Bacteroidetes, whereas the libraries from VK906/862 were dominated by members of the Proteobacteria. In addition to novel sequences, the 16S rRNA gene clone libraries revealed many bacterial sequences in common between Gulf of Mexico Lophelia corals and Norwegian fjord Lophelia corals, as well as shallow-water corals. Two Lophelia-specific bacterial groups were identified: a cluster of gammaproteobacteria related to sulfide-oxidizing gill symbionts of seep clams and a group of Mycoplasma spp. The presence of these groups in both Gulf and Norwegian Lophelia corals indicates that in spite of the geographic heterogeneity observed in Lophelia-associated bacterial communities, there are Lophelia-specific microbes.
15
Eghbert Elvan Ampou, Eghbert Eghbert Elvan, Iis Iis Triyulianti, Nuryani Widagti, Suciadi Catur Nugroho, and Yuli Pancawati. "BAKTERI PADA KARANG SCLERACTINIA DI KAWASAN PERAIRAN BUNAKEN, MOROTAI DAN RAJA AMPAT." JURNAL PESISIR DAN LAUT TROPIS 8, no. 1 (January 15, 2020): 122. http://dx.doi.org/10.35800/jplt.8.1.2020.28110.
Full textAbstract:
Research on hard coral (Scleractinian coral) contaminated with bacteria is still not much done, especially in Indonesian waters. This study took samples of coral mucus in 2010 at 3 (three) different locations, namely Bunaken (May); Morotai (September) and Raja Ampat (November), which focused on the analysis of Research on hard coral (Scleractinian coral) contaminated with bacteria is still not much done, especially in Indonesian waters. This study took samples of coral mucus in 2010 at 3 (three) different locations, namely Bunaken (May); Morotai (September) and Raja Ampat (November), which focused on the analysis of gram-positive and gram-negative bacteria. The method used for field sampling is time swim, which is by diving at a depth of 5-10 meters for ± 30 minutes and randomly taking samples of coral mucus using siring or by taking directly on corals (reef branching). Mucus samples were analyzed by bacterial isolation in the laboratory. The result shows that there were differences between gram-positive and gram-negative bacteria in the three research sites and that gram-positive bacteria were higher or dominant. Further research that can identify the bacteria species and explain its relationship to the ecosystem is highly recommended.Keywords: Bacteria, Scleractinian coral, gram-positive and -negative, Bunaken, Morotai, Raja Ampat AbstrakPenelitian tentang karang keras (Scleractinian coral) yang terkontaminasi bakteri masih belum banyak dilakukan, terutama di perairan Indonesia. Penelitian ini mengambil sampel mucus karang pada tahun 2010 di 3 (tiga) lokasi berbeda, yakni Bunaken (Mei); Morotai (September) dan Raja Ampat (November), yang difokuskan pada analisis bakteri gram postif dan gram negatif. Metode yang digunakan untuk pengambilan sampel di lapangan adalah time swim, yaitu dengan penyelaman pada kedalaman 5-10 meter selama ±30 menit dan mengambil sampel mucus karang secara acak menggunakan siring atau dengan mengambil langsung pada karang (fraksi cabang). Sampel mucus dianalisis dengan cara isolasi bakteri di laboratorium. Hasil analisis menunjukkan bahwa ada perbedaan antara bakteri gram positif dan gram negative di tiga lokasi survei dan bakteri gram positif lebih tinggi atau dominan. Penelitian lebih lanjut yang dapat menentukan jenis bakteri serta menjelaskan hubungannya dengan ekosistem sangat disarankan untuk dilakukan.Kata Kunci : Bakteri, Scleractinian coral, gram positif dan negatif, Bunaken, Morotai, Raja Ampat
16
Ampou, Eghbert Elvan, Iis Triyulianti, Nuryani Widagti, Suciadi Catur Nugroho, and Yuli Pancawati. "BAKTERI PADA KARANG SCLERACTINIA DI KAWASAN PERAIRAN BUNAKEN, MOROTAI DAN RAJA AMPAT." JURNAL PESISIR DAN LAUT TROPIS 8, no. 1 (January 15, 2020): 122. http://dx.doi.org/10.35800/jplt.8.1.2020.28128.
Full textAbstract:
Research on hard coral (Scleractinian coral) contaminated with bacteria is still not much done, especially in Indonesian waters. This study took samples of coral mucus in 2010 at 3 (three) different locations, namely Bunaken (May); Morotai (September) and Raja Ampat (November), which focused on the analysis of Research on hard coral (Scleractinian coral) contaminated with bacteria is still not much done, especially in Indonesian waters. This study took samples of coral mucus in 2010 at 3 (three) different locations, namely Bunaken (May); Morotai (September) and Raja Ampat (November), which focused on the analysis of gram-positive and gram-negative bacteria. The method used for field sampling is time swim, which is by diving at a depth of 5-10 meters for ± 30 minutes and randomly taking samples of coral mucus using siring or by taking directly on corals (reef branching). Mucus samples were analyzed by bacterial isolation in the laboratory. The result shows that there were differences between gram-positive and gram-negative bacteria in the three research sites and that gram-positive bacteria were higher or dominant. Further research that can identify the bacteria species and explain its relationship to the ecosystem is highly recommended.Keywords: Bacteria, Scleractinian coral, gram-positive and -negative, Bunaken, Morotai, Raja Ampat AbstrakPenelitian tentang karang keras (Scleractinian coral) yang terkontaminasi bakteri masih belum banyak dilakukan, terutama di perairan Indonesia. Penelitian ini mengambil sampel mucus karang pada tahun 2010 di 3 (tiga) lokasi berbeda, yakni Bunaken (Mei); Morotai (September) dan Raja Ampat (November), yang difokuskan pada analisis bakteri gram postif dan gram negatif. Metode yang digunakan untuk pengambilan sampel di lapangan adalah time swim, yaitu dengan penyelaman pada kedalaman 5-10 meter selama ±30 menit dan mengambil sampel mucus karang secara acak menggunakan siring atau dengan mengambil langsung pada karang (fraksi cabang). Sampel mucus dianalisis dengan cara isolasi bakteri di laboratorium. Hasil analisis menunjukkan bahwa ada perbedaan antara bakteri gram positif dan gram negative di tiga lokasi survei dan bakteri gram positif lebih tinggi atau dominan. Penelitian lebih lanjut yang dapat menentukan jenis bakteri serta menjelaskan hubungannya dengan ekosistem sangat disarankan untuk dilakukan.Kata Kunci : Bakteri, Scleractinian coral, gram positif dan negatif, Bunaken, Morotai, Raja Ampat
17
Conlan, Jessica A., Melissa M. Rocker, and David S. Francis. "A comparison of two common sample preparation techniques for lipid and fatty acid analysis in three different coral morphotypes reveals quantitative and qualitative differences." PeerJ 5 (August 2, 2017): e3645. http://dx.doi.org/10.7717/peerj.3645.
Full textAbstract:
Lipids are involved in a host of biochemical and physiological processes in corals. Therefore, changes in lipid composition reflect changes in the ecology, nutrition, and health of corals. As such, accurate lipid extraction, quantification, and identification is critical to obtain comprehensive insight into a coral’s condition. However, discrepancies exist in sample preparation methodology globally, and it is currently unknown whether these techniques generate analogous results. This study compared the two most common sample preparation techniques for lipid analysis in corals: (1) tissue isolation by air-spraying and (2) crushing the coral in toto. Samples derived from each preparation technique were subsequently analysed to quantify lipids and their constituent classes and fatty acids in four common, scleractinian coral species representing three distinct morphotypes (Acropora millepora, Montipora crassotuberculata, Porites cylindrica, and Pocillopora damicornis). Results revealed substantial amounts of organic material, including lipids, retained in the skeletons of all species following air-spraying, causing a marked underestimation of total lipid concentration using this method. Moreover, lipid class and fatty acid compositions between the denuded skeleton and sprayed tissue were substantially different. In particular, the majority of the total triacylglycerol and total fatty acid concentrations were retained in the skeleton (55–69% and 56–64%, respectively). As such, the isolated, sprayed tissue cannot serve as a reliable proxy for lipid quantification or identification in the coral holobiont. The in toto crushing method is therefore recommended for coral sample preparation prior to lipid analysis to capture the lipid profile of the entire holobiont, permitting accurate diagnoses of coral condition.
18
Messyasz, Adriana, Rebecca L. Maher, Sonora S. Meiling, and Rebecca Vega Thurber. "Nutrient Enrichment Predominantly Affects Low Diversity Microbiomes in a Marine Trophic Symbiosis between Algal Farming Fish and Corals." Microorganisms 9, no. 9 (September 3, 2021): 1873. http://dx.doi.org/10.3390/microorganisms9091873.
Full textAbstract:
While studies show that nutrient pollution shifts reef trophic interactions between fish, macroalgae, and corals, we know less about how the microbiomes associated with these organisms react to such disturbances. To investigate how microbiome dynamics are affected during nutrient pollution, we exposed replicate Porites lobata corals colonized by the fish Stegastes nigricans, which farm an algal matrix on the coral, to a pulse of nutrient enrichment over a two-month period and examined the microbiome of each partner using 16S amplicon analysis. We found 51 amplicon sequence variants (ASVs) shared among the three hosts. Coral microbiomes had the lowest diversity with over 98% of the microbiome dominated by a single genus, Endozoicomonas. Fish and algal matrix microbiomes were ~20 to 70× more diverse and had higher evenness compared to the corals. The addition of nutrients significantly increased species richness and community variability between samples of coral microbiomes but not the fish or algal matrix microbiomes, demonstrating that coral microbiomes are less resistant to nutrient pollution than their trophic partners. Furthermore, the 51 common ASVs within the 3 hosts indicate microbes that may be shared or transmitted between these closely associated organisms, including Vibrionaceae bacteria, many of which can be pathogenic to corals.
19
Keshavmurthy, Shashank, Kuo-Hsun Tang, Chia-Min Hsu, Chai-Hsia Gan, Chao-Yang Kuo, Keryea Soong, Hong-Nong Chou, and Chaolun Allen Chen. "Symbiodiniumspp. associated with scleractinian corals from Dongsha Atoll (Pratas), Taiwan, in the South China Sea." PeerJ 5 (January 18, 2017): e2871. http://dx.doi.org/10.7717/peerj.2871.
Full textAbstract:
Dongsha Atoll (also known as Pratas) in Taiwan is the northernmost atoll in the South China Sea and a designated marine national park since 2007. The marine park’s scope of protection covers the bio-resources of its waters in addition to uplands, so it is important to have data logging information and analyses of marine flora and fauna, including their physiology, ecology, and genetics. As part of this effort, we investigatedSymbiodiniumassociations in scleractinian corals from Dongsha Atoll through surveys carried out at two depth ranges (shallow, 1–5 m; and deep, 10–15 m) in 2009 and during a bleaching event in 2010.Symbiodiniumcomposition was assessed using restriction fragment length polymorphism (RFLP) of 28S nuclear large subunit ribosomal DNA (nlsrDNA). Our results showed that the 796 coral samples from seven families and 20 genera collected in 2009 and 132 coral samples from seven families and 12 genera collected in 2010 were associated withSymbiodiniumC, D and C+D. Occurrence of clade D in shallow water (24.5%) was higher compared to deep (14.9%). Due to a bleaching event in 2010, up to 80% of coral species associated withSymbiodiniumC underwent moderate to severe bleaching. Using the fine resolution technique of denaturing gradient gel electrophoresis (DGGE) of internal transcribed spacer 2 (ITS2) in 175 randomly selected coral samples, from 2009 and 2010, eightSymbiodiniumC types and twoSymbiodiniumD types were detected. This study is the first baseline survey onSymbiodiniumassociations in the corals of Dongsha Atoll in the South China Sea, and it shows the dominance ofSymbiodiniumclade C in the population.
20
Wagner, Amy J., Thomas P. Guilderson, Niall C. Slowey, and Julia E. Cole. "Pre-Bomb Surface Water Radiocarbon of the Gulf of Mexico and Caribbean as Recorded in Hermatypic Corals." Radiocarbon 51, no. 3 (2009): 947–54. http://dx.doi.org/10.1017/s0033822200034020.
Full textAbstract:
Radiocarbon measurements of hermatypic corals from 4 sites in the Gulf of Mexico (GOM) and Caribbean Sea were made to estimate the marine 14C reservoir age (R) and the marine regional correction (ΔR) for this region. Coral skeletal material from the Flower Garden Banks (northern GOM continental shelf), Veracruz, Mexico, and 2 reefs from the Cariaco Basin, Venezuela, were analyzed. Annual and subannual samples from 1945–1955 were milled and 14C composition was determined. In the Gulf of Mexico, average coral Δ14C is −52.6 ± 0.7‰ and average Δ14C for the Cariaco Basin corals is −53.4 ± 0.8‰. Average values for the marine reservoir age and ΔR are computed with this data and compared with results derived from previous measurements made in the same regions. These values are important in calibrating the 14C ages of carbonate samples from the area.
21
MATTAN-MOORGAWA, SUSHMA, SOONIL DDV RUGHOOPUTH, and RANJEET BHAGOOLI. "Variable PSII functioning and bleaching conditions of tropical scleractinian corals pre-and post-bleaching event." Ocean Life 2, no. 1 (June 1, 2018): 1–10. http://dx.doi.org/10.13057/oceanlife/o020101.
Full textAbstract:
Mattan-Moorgawa S, Rughooputh SDDV, Bhagooli R. 2017. Variable PSII functioning and bleaching conditions of tropical scleractinian corals pre-and post-bleaching event. Ocean Life 1: 1-10. This study compared pre-bleaching and post-bleaching conditions of eight reef-building corals, Acropora cytherea, Acropora hyacynthus, Acropora muricata, Acropora sp., Pocillopora damicornis, Pocillopora eydouxi, Galaxea fascicularis and Fungia sp., in terms of visual coloration (non-bleached (NB), pale (P), partially bleached (PB) and bleached (B)) and chlorophyll fluorescence yield at photosystem II (PSII)). A total of twenty colonies from twelve stations along four transects were surveyed at Belle-Mare, Mauritius, from October 2008 to October 2009, and compared to the CoralWatch Coral Health Chart. PSII functioning, measured as Fv/Fm, were recorded in coral samples using a pulse-amplitudemodulated (PAM) fluorometer. Physico-chemical parameters (sea surface temperature, dissolved oxygen, salinity and pH) were recorded in situ. An increase in SST up to 31.4ºC in February 2009 triggered the bleaching event observed in May 2009 at the site. Acroporids showed the first sign of bleaching and paling as from January 2009 when mean SST was at 30ºC. Branching coral (P. eydouxi) and solitary coral (Fungia sp.) exhibited only 15% of their colonies showing paling by April 2009. A. cytherea, A. hyacynthus, and A. muricata showed varying bleaching conditions [Pale (P), Partially-bleached (PB) and Bleached (B)] at onset of the bleaching event whilst Acropora sp. showed only a paling of its colonies. Post-bleaching data indicated a differential recovery in visual coloration and PSII functioning among the corals. P. eydouxi and Fungia sp. showed no bleaching conditions throughout the study. P. damicornis and G. fascicularis indicated a quick coloration recovery from P to NB after the bleaching event, although their maximum quantum yield at PSII did not show significant changes in P and NB samples. A. muricata recovered faster than A. hyacynthus and A. cytherea in terms of PSII functioning. A differential recovery was observed post-bleaching event among the eight coral species, in terms of recovery of color and PSII functioning. The order of recovery was as follows: massive-like/ solitary corals > branching and semi-bulbous corals > tabular corals.
22
Dalit, Keren, Eviatar, Hiba, Gal, Ehud, Yossi, and Oren. "The Algal Symbiont Modifies the Transcriptome of the Scleractinian Coral Euphyllia paradivisa During Heat Stress." Microorganisms 7, no. 8 (August 12, 2019): 256. http://dx.doi.org/10.3390/microorganisms7080256.
Full textAbstract:
The profound mutualistic symbiosis between corals and their endosymbiotic counterparts, Symbiodiniaceae algae, has been threatened by the increase in seawater temperatures, leading to breakdown of the symbiotic relationship—coral bleaching. To characterize the heat-stress response of the holobiont, we generated vital apo-symbiotic Euphyllia paradivisa corals that lacked the endosymbiotic algae. Using RNA sequencing, we analyzed the gene expression of these apo-symbionts vs. symbiotic ones, to test the effect of the algal presence on the tolerance of the coral. We utilized literature-derived lists of “symbiosis differentially expressed genes” and “coral heat-stress genes” in order to compare between the treatments. The symbiotic and apo-symbiotic samples were segregated into two separate groups with several different enriched gene ontologies. Our findings suggest that the presence of endosymbionts has a greater negative impact on the host than the environmental temperature conditions experienced by the holobiont. The peak of the stress reaction was identified as 28 °C, with the highest number of differentially expressed genes. We suggest that the algal symbionts increase coral holobiont susceptibility to elevated temperatures. Currently, we can only speculate whether coral species, such as E. paradivisa, with the plasticity to also flourish as apo-symbionts, may have a greater chance to withstand the upcoming global climate change challenge.
23
Dalton, S. J., S. Godwin, S. D. A. Smith, and L. Pereg. "Australian subtropical white syndrome: a transmissible, temperature-dependent coral disease." Marine and Freshwater Research 61, no. 3 (2010): 342. http://dx.doi.org/10.1071/mf09060.
Full textAbstract:
Since 2000, a disease displaying white-syndrome characteristics has been observed affecting corals from the genus Turbinaria in the Solitary Islands Marine Park, New South Wales, Australia. Recently termed Australian subtropical white syndrome, this disease is transmissible through direct contact and by a predatory vector, but transmission through the water column has not been observed. In aquarium experiments, progressive tissue loss, extending from the region where healthy Turbinaria mesenterina fragments were in direct contact with samples of diseased coral, was noted in 66% of treatments. No tissue loss occurred in any of the controls or when healthy fragments were not in direct contact with diseased corals. Field experiments confirmed that the disease was infectious through direct contact. Further experiments showed that the rate of tissue loss was significantly higher when corals were exposed to summer temperatures (26°C). These results suggest that temperature increases predicted in most climate change models could lead to the loss of dominant coral species, displacing other organisms that rely on corals for food and shelter. Finally, the present study showed that removal of the disease margin provides a management tool to minimise coral tissue loss during an epizootic.
24
Matus, Ilse Valenzuela, Jorge Lino Alves, Joaquim Góis, Augusto Barata da Rocha, Rui Neto, and Carlos Da Silva Mota. "Effect of 3D printer enabled surface morphology and composition on coral growth in artificial reefs." Rapid Prototyping Journal 27, no. 4 (March 29, 2021): 692–706. http://dx.doi.org/10.1108/rpj-07-2020-0165.
Full textAbstract:
Purpose The purpose of this paper is to prove and qualify the influence of textured surface substrates morphology and chemical composition on the growth and propagation of transplanted corals. Use additive manufacturing and silicone moulds for converting three-dimensional samples into limestone mortar with white Portland cement substrates for coral growth. Design/methodology/approach Tiles samples were designed and printed with different geometries and textures inspired by nature marine environment. Commercial coral frag tiles were analysed through scanning electron microscopy (SEM) to identify the main chemical elements. Raw materials and coral species were selected. New base substrates were manufactured and deployed into a closed-circuit aquarium to monitor the coral weekly evolution process and analyse the results obtained. Findings Experimental results provided positive statistical parameters for future implementation tests, concluding that the intensity of textured surface, interfered favourably in the coralline algae biofilm growth. The chemical composition and design of the substrates were determinant factors for successful coral propagation. Recesses and cavities mimic the natural rocks aspect and promoted the presence and interaction of other species that favour the richness of the ecosystem. Originality/value Additive manufacturing provided an innovative method of production for ecology restoration areas, allowing rapid prototyping of substrates with high complexity morphologies, a critical and fundamental attribute to guarantee coral growth and Crustose Coralline Algae. The result of this study showed the feasibility of this approach using three-dimensional printing technologies.
25
Huda, Miftahul, Suwarno Hadisusanto, and Encus Widyatmoko. "CORAL REEF CONDITION AND HARD CORAL (SCLERACTINIA) COMUNITY IN LOCAL MARINE CONSERVATION AREA, BENGKAYANG, WEST KALIMANTAN." KnE Life Sciences 2, no. 1 (September 20, 2015): 507. http://dx.doi.org/10.18502/kls.v2i1.205.
Full textAbstract:
<p>Coral reef ecosystem has diverse shape and stunning beauty. It has high value on both ecological and economical aspect it has productivity greater than other marine life. Local Marine Conservation Area, Bengkayang, West Kalimantan (Lemukutan island, Penata Besar island, Penata Kecil island, Seluas island, Rahdayan island) has a high potential on coastal and marine natural resources especially coral reefs ecosystem. The study was purposed to determine the condition coral reef ecosystem and the diversity of hard corals (Scleractinia). Samples have been taking from 5-7 meters depth in every point using Line Intercept Transect method (LIT). The observation result from the coral reef in Local Marine Conservation Area showed as the followings varies from bad to good (13.82 – 69.00%), but biotic components were found in each area that consist of sediment with percentage of 4.32-37.68% and the rock of 2.57- 38.22%. Hard coral community consists of 35 species including seven families. Genus Acropora as hard coral species is dominating the five islands. The damage of coral reefs that occurs in most of the study area is due to increased suspended material (sediments). </p><p><strong>Keywords</strong>: Coral reefs, Scleractinia, Acropora, LIT, Local Marine Conservation Area, Bengkayang, West Kalimantan.</p>
26
Hong, Mei-Jhu, Yi-Ting Yu, Chaolun A. Chen, Pei-Wen Chiang, and Sen-Lin Tang. "Influence of Species Specificity and Other Factors on Bacteria Associated with the Coral Stylophora pistillata in Taiwan." Applied and Environmental Microbiology 75, no. 24 (October 23, 2009): 7797–806. http://dx.doi.org/10.1128/aem.01418-09.
Full textAbstract:
ABSTRACT Species of bacteria associated with Stylophora pistillata were determined by analyses of 16S ribosomal genes. Coral samples were taken from two distinct sites at Kenting, in the far south of Taiwan; three coral colonies at each site were tagged and sampled in the winter and summer of 2007. Six hundred 16S rRNA gene clones were selected and sequenced for diversity analysis and community comparison. LIBSHUFF and nonparametric multiple dimensional scaling analyses showed variations in the composition of the coral-associated bacteria in the different samples, suggesting that seasonal and geographic factors and variations in individual coral colonies were all vital drivers of the structure of the S. pistillata-associated bacterial community. To examine the association between species specificity and environmental impacts on the structure of the coral-associated bacterial community, we conducted an integrated, comparative analysis of 44 coral-associated bacterial data sets, including the present study's data. The clustering analysis suggests that the influence of spatial and temporal factors on the coral-associated bacteria population structure is considerable; nonetheless, the effect of species specificity is still detectable in some coral species, especially those from the Caribbean Sea.
27
Anderson, David A., Marcus E. Walz, Ernesto Weil, Peter Tonellato, and Matthew C. Smith. "RNA-Seq of the Caribbean reef-building coralOrbicella faveolata(Scleractinia-Merulinidae) under bleaching and disease stress expands models of coral innate immunity." PeerJ 4 (February 15, 2016): e1616. http://dx.doi.org/10.7717/peerj.1616.
Full textAbstract:
Climate change-driven coral disease outbreaks have led to widespread declines in coral populations. Early work on coral genomics established that corals have a complex innate immune system, and whole-transcriptome gene expression studies have revealed mechanisms by which the coral immune system responds to stress and disease. The present investigation expands bioinformatic data available to study coral molecular physiology through the assembly and annotation of a reference transcriptome of the Caribbean reef-building coral,Orbicella faveolata. Samples were collected during a warm water thermal anomaly, coral bleaching event and Caribbean yellow band disease outbreak in 2010 in Puerto Rico. Multiplex sequencing of RNA on the Illumina GAIIx platform and de novo transcriptome assembly by Trinity produced 70,745,177 raw short-sequence reads and 32,463O. faveolatatranscripts, respectively. The reference transcriptome was annotated with gene ontologies, mapped to KEGG pathways, and a predicted proteome of 20,488 sequences was generated. Protein families and signaling pathways that are essential in the regulation of innate immunity across Phyla were investigated in-depth. Results were used to develop models of evolutionarily conserved Wnt, Notch, Rig-like receptor, Nod-like receptor, and Dicer signaling.O. faveolatais a coral species that has been studied widely under climate-driven stress and disease, and the present investigation provides new data on the genes that putatively regulate its immune system.
28
Esquivel-Garrote, Octavio, and Álvaro Morales-Ramírez. "Nocturnal variation of the zooplankton community in coral reef substrates at Isla del Coco National Park (Eastern Tropical Pacific)." Revista de Biología Tropical 68, S1 (March 24, 2020): S261—S270. http://dx.doi.org/10.15517/rbt.v68is1.41189.
Full textAbstract:
Introduction: Zooplankton is a major link in coral reef food webs and a source of nutrients for corals. Demersal zooplankton in coral reefs makes diel migrations at night to avoid predation by fish and corals, increasing abundance and biomass at night. Objectives: To study the composition and variation of the demersal and pelagic zooplankton community at night and to increase the taxonomic knowledge of the benthic copepod fauna over different substrates of a coral reef. Methods: Traps made of plastic, with a 100 μm mesh size collector cup attached, were placed for 12 hours between 5-10 m depth over four substrates: (1) sand, (2) small and (3) big colonies of Porites lobata, and (4) dead and alive corals. Sampling started at dusk (1800 h), and the collector cups were collected and replaced at 2100 and 0000, and the last samples removed at down (0600 h). Results: The highest abundance of zooplankton was capture over P. lobata colonies between 0000 to 0600 h. Copepods (adults, copepodites, and nauplii) dominated the community structure and were more abundant during all the time intervals and substrates. Pelagic copepods were more abundant than the benthic, however, not more diverse. Among the benthic copepods, 20 new records of harpacticoids and calanoids were registered for Isla del Coco and Costa Rican waters. Appendicularians and decapod larvae were also abundant. Changes in coral reef community structure were related with time and not with the kind of substrate, although some taxa were found only in a specific time interval or substrate. Conclusions: Community structure and abundance of demersal and pelagic coral reef zooplankton in Chatham Bay were dominated by copepods, larvaceans and decapod larvae, similar to other coral reefs around the world. The highest abundance peak of organisms in the water column between 0000 to 0600 h could be related to diel migration.
29
Weisler, Marshall I., Quan Hua, and Jian-xin Zhao. "Late Holocene14C Marine Reservoir Corrections for Hawai'I Derived from U-Series Dated Archaeological Coral." Radiocarbon 51, no. 3 (2009): 955–68. http://dx.doi.org/10.1017/s0033822200034032.
Full textAbstract:
The first application of U-series dating and accelerator mass spectrometry (AMS) assay of Polynesian archaeologicalPocilloporaspp. branch corals for deriving a precise local marine reservoir correction (ΔR) is described. Known-age corals were selected that spanned the entire culture-historical sequence for the Hawaiian Islands, thus eliminating the problem of not having known-age dated samples that cover the period of direct relevance to prehistorians; in this case, about AD 700–1800. Dating coral samples from windward and leeward coastlines of Moloka'i Island, with different offshore conditions such as upwelling, currents, wind patterns, coastal topography, and straight or embayed shorelines, provides insights into possible variations of local conditions on the same island—something that has never been attempted. In this regard, there was no spatial variability in ΔR during the 17th century. We report a weighted average ΔR value for Moloka'i Island of 52 ± 25 yr using 12 pair-dated dedicatory branch corals from religious archaeological sites and demonstrate that there is no significant temporal variability in ΔR between about AD 700 to 1800. In combination with 4 selected previously published ΔR values based on pre-bomb known-age marine shells, a revised ΔR of 66 ± 54 yr is established for the Hawaiian Islands. However, future research should examine the archipelago-wide spatial variability in ΔR with the analysis of additional dated archaeological coral samples.
30
Miranda, Ricardo J., Igor C. S. Cruz, and Zelinda M. A. N. Leão. "Coral bleaching in the Caramuanas reef (Todos os Santos Bay, Brazil) during the 2010 El Niño event." Latin American Journal of Aquatic Research 41, no. 2 (May 2, 2017): 351–60. http://dx.doi.org/10.3856/vol41-issue2-fulltext-14.
Full textAbstract:
Episodes of coral bleaching related to El Niño events have been increasing in frequency and severity. This phenomenon is cited as a major cause of degradation of coral reefs. This study evaluates the effects of coral bleaching on the Caramuanas reef community, which occurred during the southern hemisphere summer of 2009/2010. Within this period the sea surface temperature of 31°C and thermal anomalies up to almost 1°C were recorded. During and after this El Niño event, frequency and severity of bleaching, live coral cover, number of colonies, class size, disease occurrence, and mortality rate were monitored on corals larger than 20 cm in diameter. The samples were taken at twelve fixed transects, in three reef stations. Statistical analysis showed that the severity of bleaching was different between the two periods, during and after the 2010 ENSO event. The Caramuanas reef showed sublethal bleaching effects indicating that this reef is tolerant to bleaching when the temperature anomalies do not exceed 0.75°C within one week.
31
Adkins, Jess F., Shelia Griffin, Michaele Kashgarian, Hai Cheng, E. R. M. Druffel, E. A. Boyle, R. Lawrence Edwards, and Chuan-Chou Shen. "Radiocarbon Dating of Deep-Sea Corals." Radiocarbon 44, no. 2 (2002): 567–80. http://dx.doi.org/10.1017/s0033822200031921.
Full textAbstract:
Deep-sea corals are a promising new archive of paleoclimate. Coupled radiocarbon and U-series dates allow 14C to be used as a tracer of ocean circulation rate in the same manner as it is used in the modern ocean. Diagenetic alteration of coral skeletons on the seafloor requires a thorough cleaning of contaminating phases of carbon. In addition, 10% of the coral must be chemically leached prior to dissolution to remove adsorbed modern CO2. A survey of modern samples from the full δ14C gradient in the deep ocean demonstrates that the coralline CaCO3 records the radiocarbon value of the dissolved inorganic carbon.
32
Canizales-Flores, Hazel M., Alma P. Rodríguez-Troncoso, Eric Bautista-Guerrero, and Amílcar L. Cupul-Magaña. "Molecular Phylogenetics of Trapezia Crabs in the Central Mexican Pacific." Oceans 1, no. 3 (August 26, 2020): 156–64. http://dx.doi.org/10.3390/oceans1030011.
Full textAbstract:
To date, Trapezia spp. crabs have been considered obligate symbionts of pocilloporid corals. They protect their coral hosts from predators and are essential for the health of certain coral species. However, the basic details of this group of crustaceans are lacking, and there is a need for species-level molecular markers. The Tropical Eastern Pacific (TEP) region harbors important coral communities mainly built by corals of the genus Pocillopora, with three known Trapezia species known to associate with them: Trapezia bidentata, T. formosa and T. corallina. Both taxonomic and molecular analyses were carried out with samples of all three crab species collected from Pocillopora spp. in the Central Mexican Pacific. Analysis of both a mitochondrial and a nuclear gene revealed only two species, T. corallina and T. bidentata. T. formosa however appears to be a morphotype of T. bidentata. The use of integrative taxonomy for this group has increased the knowledge of the biodiversity not only of the study area, but of the whole TEP and will enhance the future study of the Trapezia–Pocillopora symbiosis.
33
Saunders, Sandra M., Ben Radford, Sarah A. Bourke, Zoe Thiele, Tina Bech, and Jerome Mardon. "A Rapid Method for Determining Lipid Fraction Ratios of Hard Corals under Varying Sediment and Light Regimes." Environmental Chemistry 2, no. 4 (2005): 331. http://dx.doi.org/10.1071/en05043.
Full textAbstract:
Environmental Context.Monitoring the health of coral reef systems is vitally important to maintain and manage these threatened, complex and biodiverse natural ecosystems. Although total lipid content has been suggested as a potential index of coral condition, current methods of measurement are time consuming, technically challenging and expensive. These limitations have prohibited the application of coral lipid content as an impact-monitoring tool. The development of a practical and rapid method to determine lipid fraction ratios has the potential to lead towards an effective tool for coral reef monitoring. Abstract.Lipid content has been used as a measure of energetic status and condition in a number of fish and invertebrate species and can potentially be applied to hard corals. However, common methods for measuring lipid content are time consuming, technically challenging and expensive and these limitations have prohibited the application of lipid content as an impact-monitoring tool. To overcome these limitations, a rapid low-tech method for determining neutral to polar lipid ratios from hard coral tissue samples has been developed. This paper describes the development of the method together with a preliminary application of the technique carried out in a field study to determine whether the relative amounts of non-polar storage lipid to polar structural lipid may provide insight into the nutritional condition of individual coral colonies under differing environmental stresses. Variation in the lipid ratios of the hard coral Acropora nobilis, collected from the Montebello Islands off Western Australia, was correlated with local light and sediment regimes. This initial application of the method has demonstrated the viability of the technique, which subsequently has the potential to be applied in the analysis of a large number of samples as would be required in environmental monitoring.
34
Muhammad, Fadel, Neviaty Putri Zamani, Meutia Samira Ismet, and Muhammad Irlan Assidiq Kusuma Ramadhan. "The Effect of Plastic Waste Attachment on Branching Coral to Zooxanthellae Abundance in the Kelapa Dua Island Waters, Seribu Islands." Jurnal Ilmiah Perikanan dan Kelautan 13, no. 1 (March 31, 2021): 29. http://dx.doi.org/10.20473/jipk.v13i1.18146.
Full textAbstract:
HighlightLight intensity from plastic waste was positively correlated with the abundance of zooxanthellae in corals.The abundance of zooxanthellae between sack plastic and clear plastic treatment tended to be the same.The treatment of packaging plastic was treated with the lowest light intensity.The treatment of black plastic was the treatment that produced the lowest abundance of zooxanthellae. AbstractCoral growth in Indonesia was being disrupted due to the continued threat of environmental change, such as littering to the beach. This study aimed to analyze the effect of the attachment of different colored plastic waste to the rate of zooxanthellae abundance on branching corals in Kelapa Dua Island waters. Branching coral colony samples consisted of the genus Acropora and Porites with a total of 15 fragments of coral colonies at the depth of 80-90 cm were tested with a treatment of the attachment plastic wastes (control, clear plastic, plastic sack, plastic packaging, and black plastic) for four days. The zooxanthellae abundance was calculated using the APHA (American Public Health Association) formula. The results of zooxanthellae abundance on the closure treatment of branching coral samples with black plastic and control had the lowest and highest values by 4.25 x 105 cells/cm2 and 1.38 x 106 cells/cm2. The results of the linear regression test showed that there was a significant relationship between plastic waste with low light intensity and a decrease of zooxanthellae abundance in coral colonies with the equation Y of 972.78x + 653402, determination index (R2) of 0.68, and correlation index (r) of 0.83. These results indicated that the attachment of plastic waste to branching coral colonies could be a stressor on coral animals in reducing light intensity, which caused a reduction of zooxanthellae abundance as coral endosymbiont.
35
Moynihan, Molly A., Shahrouz Amini, Nathalie F. Goodkin, Jani T. I. Tanzil, J. Q. Isaiah Chua, Gareth N. Fabbro, Tung-Yung Fan, Daniela N. Schmidt, and Ali Miserez. "Environmental impact on the mechanical properties of Porites spp. corals." Coral Reefs 40, no. 3 (March 8, 2021): 701–17. http://dx.doi.org/10.1007/s00338-021-02064-3.
Full textAbstract:
AbstractDespite the economic and ecological importance of corals’ skeletal structure, as well as their predicted vulnerability to future climate change, few studies have examined the skeletal mechanical properties at the nanoscale. As climate change is predicted to alter coral growth and physiology, as well as increase mechanical stress events (e.g., bioerosion, storm frequency), it is crucial to understand how skeletal mechanical properties change with environmental conditions. Moreover, while material properties are intimately linked to the chemical composition of the skeleton, no previous study has examined mechanical properties alongside carbonate geochemical composition. Using Porites coral cores from a wide range of reef environments (Thailand, Singapore, Taiwan), we correlated coral’s micro-mechanical properties with chemical composition. In contrast to previous mechanical measurements of reef-building corals, we document unprecedented variability in the hardness, stiffness, and micro-cracking stress of Porites corals across reef environments, which may significantly decrease the structural integrity of reef substrate. Corals from environments with low salinity and high sedimentation had higher organic content and fractured at lower loads, suggesting that skeletal organic content caused enhanced embrittlement. Within individual coral cores, we observed seasonal variability in skeletal stiffness, and a relationship between high sea surface temperature, increased stiffness, and high-density. Regionally, lower Sr/Ca and higher Mg/Ca coincided with decreased stiffness and hardness, which is likely driven by increased amorphous calcium carbonate and skeletal organic content. If the coral is significantly embrittled, as measured here in samples from Singapore, faster erosion is expected. A decrease in skeletal stiffness will decrease the quality of reef substrate, enhance the rate of bioerosion by predators and borers, and increase colony dislodgement, resulting in widespread loss of structural complexity.
36
Godinot, C., A. Tribollet, R. Grover, and C. Ferrier-Pagès. "Bioerosion by euendoliths decreases in phosphate-enriched skeletons of living corals." Biogeosciences 9, no. 7 (July 2, 2012): 2377–84. http://dx.doi.org/10.5194/bg-9-2377-2012.
Full textAbstract:
Abstract. While the role of microboring organisms, or euendoliths, is relatively well known in dead coral skeletons, their function in live corals remains poorly understood. They are suggested to behave like ectosymbionts or parasites, impacting their host's health. However, the species composition of microboring communities, their abundance and dynamics in live corals under various environmental conditions have never been explored. Here, the effect of phosphate enrichment on boring microorganisms in live corals was tested for the first time. Stylophora pistillata nubbins were exposed to 3 different treatments (phosphate concentrations of 0, 0.5 and 2.5 μmol l−1) during 15 weeks. After 15 weeks of phosphate enrichment, petrographic thin sections were prepared for observation with light microscopy, and additional samples were examined with scanning electron microscopy (SEM). Euendoliths comprised mainly phototrophic Ostreobium sp. filaments. Rare filaments of heterotrophic fungi were also observed. Filaments were densely distributed in the central part of nubbins, and less abundant towards the apex. Unexpectedly, there was a visible reduction of filament abundance in the most recently calcified apical part of phosphate-enriched nubbins. The overall abundance of euendoliths significantly decreased, from 9.12 ± 1.09% of the skeletal surface area in unenriched corals, to 5.81 ± 0.77% and 5.27 ± 0.34% in 0.5 and 2.5 μmol l−1-phosphate enriched corals respectively. SEM observations confirmed this decrease. Recent studies have shown that phosphate enrichment increases coral skeletal growth and metabolic rates, while it decreases skeletal density and resilience to mechanical stress. We thus hypothesize that increased skeletal growth in the presence of phosphate enrichment occurred too fast for an effective expansion of euendolith growth. They could not keep up with coral growth, so they became diluted in the apex areas as nubbins grew with phosphate enrichment. Results from the present study suggest that coral skeletons of S. pistillata will not be further weakened by euendoliths under phosphate enrichment.
37
Marchioro, Giulia M., Bettina Glasl, Aschwin H. Engelen, Ester A. Serrão, David G. Bourne, Nicole S. Webster, and Pedro R. Frade. "Microbiome dynamics in the tissue and mucus of acroporid corals differ in relation to host and environmental parameters." PeerJ 8 (August 17, 2020): e9644. http://dx.doi.org/10.7717/peerj.9644.
Full textAbstract:
Corals are associated with diverse microbial assemblages; however, the spatial-temporal dynamics of intra-species microbial interactions are poorly understood. The coral-associated microbial community varies substantially between tissue and mucus microhabitats; however, the factors controlling the occurrence, abundance, and distribution of microbial taxa over time have rarely been explored for different coral compartments simultaneously. Here, we test (1) differentiation in microbiome diversity and composition between coral compartments (surface mucus and tissue) of two Acropora hosts (A. tenuis and A. millepora) common along inshore reefs of the Great Barrier Reef, as well as (2) the potential linkage between shifts in individual coral microbiome families and underlying host and environmental parameters. Amplicon based 16S ribosomal RNA gene sequencing of 136 samples collected over 14 months, revealed significant differences in bacterial richness, diversity and community structure among mucus, tissue and the surrounding seawater. Seawater samples were dominated by members of the Synechococcaceae and Pelagibacteraceae bacterial families. The mucus microbiome of Acropora spp. was dominated by members of Flavobacteriaceae, Synechococcaceae and Rhodobacteraceae and the tissue was dominated by Endozoicimonaceae. Mucus microbiome in both Acropora species was primarily correlated with seawater parameters including levels of chlorophyll a, ammonium, particulate organic carbon and the sum of nitrate and nitrite. In contrast, the correlation of the tissue microbiome to the measured environmental (i.e., seawater parameters) and host health physiological factors differed between host species, suggesting host-specific modulation of the tissue-associated microbiome to intrinsic and extrinsic factors. Furthermore, the correlation between individual coral microbiome members and environmental factors provides novel insights into coral microbiome-by-environment dynamics and hence has potential implications for current reef restoration and management efforts (e.g. microbial monitoring and observatory programs).
38
Kumagai, Yuho, Norihiro Nakamura, Tetsuro Sato, Toshitaka Oka, and Hirokuni Oda. "Ferromagnetic Resonance Spectroscopy and Rock Magnetic Characterization of Fossil Coral Skeletons in Ishigaki Islands, Japan." Geosciences 8, no. 11 (November 2, 2018): 400. http://dx.doi.org/10.3390/geosciences8110400.
Full textAbstract:
Skeletons of hermatypic corals (e.g., Porites) might have enormous potential as a high-resolution paleomagnetic recorder owing to their rapid and continuous growth over hundreds of years at a rate of up to 2 cm/year, although typical corals show an extremely weak intensity of remanence and low stability. We found that coral tsunami boulders with negligible amounts of calcite on Ishigaki Island show a measurable intensity of remanence; thus, we attempted to characterize the magnetic assemblages in this coral skeleton to determine whether it is of biogenic or detrital magnetite using first-order reversal curve (FORC) measurements, ferromagnetic resonance (FMR) spectroscopy, and petrological observations through field-emission type scanning electron microscope (FE-SEM) with an acid treatment. The FMR derivative spectra of coral skeleton samples represent multiple derivative maxima and extended low-field absorption, indicating the presence of intact biogenic magnetite chains. FORC diagrams represent a “central ridge” signature with a vertical spread. These FMR and FORC features indicate the magnetization of these coral skeletons that are mainly created using intact biogenic magnetites and mixtures of grains from collapsed biogenic magnetites, pseudo-single domain grains, and multi-domain grains such as detrital magnetite. FE-SEM observations confirm the presence of a chain-like structure of iron oxides corresponding to the features of biogenic magnetite. Therefore, the magnetic mineral assemblage in coralline boulders from Ishigaki Island consists of dominant biogenic-origin single-domain magnetite and a trace amount of detrital component, indicating that fossil coral skeletons in Ishigaki Island have potential for utilization in paleomagnetic studies.
39
Rincón-Tomás, Blanca, Jan-Peter Duda, Luis Somoza, Francisco Javier González, Dominik Schneider, Teresa Medialdea, Esther Santofimia, et al. "Cold-water corals and hydrocarbon-rich seepage in Pompeia Province (Gulf of Cádiz) – living on the edge." Biogeosciences 16, no. 7 (April 16, 2019): 1607–27. http://dx.doi.org/10.5194/bg-16-1607-2019.
Full textAbstract:
Abstract. Azooxanthellate cold-water corals (CWCs) have a global distribution and have commonly been found in areas of active fluid seepage. The relationship between the CWCs and these fluids, however, is not well understood. This study aims to unravel the relationship between CWC development and hydrocarbon-rich seepage in Pompeia Province (Gulf of Cádiz, Atlantic Ocean). This region is comprised of mud volcanoes (MVs), coral ridges and fields of coral mounds, which are all affected by the tectonically driven seepage of hydrocarbon-rich fluids. These types of seepage, for example, focused, scattered, diffused or eruptive, is tightly controlled by a complex system of faults and diapirs. Early diagenetic carbonates from the currently active Al Gacel MV exhibit δ13C signatures down to −28.77 ‰ Vienna Pee Dee Belemnite (VPDB), which indicate biologically derived methane as the main carbon source. The same samples contain 13C-depleted lipid biomarkers diagnostic for archaea such as crocetane (δ13C down to −101.2 ‰ VPDB) and pentamethylicosane (PMI) (δ13C down to −102.9 ‰ VPDB), which is evidence of microbially mediated anaerobic oxidation of methane (AOM). This is further supported by next generation DNA sequencing data, demonstrating the presence of AOM-related microorganisms (ANMEs, archaea, sulfate-reducing bacteria) in the carbonate. Embedded corals in some of the carbonates and CWC fragments exhibit less negative δ13C values (−8.08 ‰ to −1.39 ‰ VPDB), pointing against the use of methane as the carbon source. Likewise, the absence of DNA from methane- and sulfide-oxidizing microbes in sampled coral does not support the idea of these organisms having a chemosynthetic lifestyle. In light of these findings, it appears that the CWCs benefit rather indirectly from hydrocarbon-rich seepage by using methane-derived authigenic carbonates as a substratum for colonization. At the same time, chemosynthetic organisms at active sites prevent coral dissolution and necrosis by feeding on the seeping fluids (i.e., methane, sulfate, hydrogen sulfide), allowing cold-water corals to colonize carbonates currently affected by hydrocarbon-rich seepage.
40
Stolarski, J., R. Przeniosło, M. Mazur, and M. Brunelli. "High-resolution synchrotron radiation studies on natural and thermally annealed scleractinian coral biominerals." Journal of Applied Crystallography 40, no. 1 (January 12, 2007): 2–9. http://dx.doi.org/10.1107/s002188980604489x.
Full textAbstract:
The structural phase transition from aragonite to calcite in biogenic samples extracted from the skeletons of selected scleractinian corals has been studied by synchrotron radiation diffraction. Biogenic aragonite samples were extracteden blocwithout pulverization from two ecologically different scleractinian taxa:Desmophyllum(deep-water, solitary and azooxanthellate) andFavia(shallow-water, colonial, zooxanthellate). It was found that natural (not pulverized) samples contribute to narrow Bragg peaks with Δd/dvalues as low as 1 × 10−3, which allows the exploitation of the high resolution of synchrotron radiation diffraction. A precise determination of the lattice parameters of biogenic scleractinian coral aragonite shows the same type of changes of thea,b,clattice parameter ratios as that reported for aragonite extracted from other invertebrates [Pokroy, Quintana, Caspi, Berner & Zolotoyabko (2004).Nat. Mater.3, 900–902]. It is believed that the crystal structure of biogenic samples is influenced by interactions with organic molecules that are initially present in the biomineralization hydrogel. The calcite phase obtained by annealing the coral samples has a considerably different unit-cell volume and lattice parameter ratioc/aas compared with reference geological calcite and annealed synthetic aragonite. The internal strain in the calcite structure obtained by thermal annealing of the biomineral samples is about two times larger than that found in the natural aragonite structure. This effect is observed despite slow heating and cooling of the sample.
41
Barnett, Beverly K., Laura Thornton, Robert Allman, Jeffrey P. Chanton, and William F. Patterson. "Linear decline in red snapper (Lutjanus campechanus) otolith Δ14C extends the utility of the bomb radiocarbon chronometer for fish age validation in the Northern Gulf of Mexico." ICES Journal of Marine Science 75, no. 5 (May 3, 2018): 1664–71. http://dx.doi.org/10.1093/icesjms/fsy043.
Full textAbstract:
Abstract Radiocarbon (Δ14C) was analyzed in northern Gulf of Mexico (nGOM) red snapper (Lutjanus campechanus) otolith cores (n = 23), otolith edge samples (n = 12), and whole age-0 otoliths (n = 9), with edge samples and whole age-0 otoliths constituting known-age samples. There was no significant difference in the linear relationship of Δ14C versus year of formation between regional corals and known-age otolith samples, and a linear regression fit to the combined data from 1980 to 2015 extends the utility of the bomb radiocarbon chronometer for age validation. The entire regional coral and known-age otolith data set (1940 to 2015) was then utilized as a reference series to validate otolith-derived red snapper age estimates for cored otolith samples. A loess regression was fit to the reference data and then the sum of squared residuals (SSR) was computed from predicted versus observed birth years for cored adult otolith samples. This process was then repeated for ages biased ±1–4 years. Ages with no bias applied had the lowest SSR, thus validating red snapper age estimates and demonstrating the utility of the combined regional coral and known-age red snapper otolith Δ14C time series for age validation of nGOM marine fishes.
42
Mayal, Elga Miranda, Sigrid Neumann-Leitão, Fernando Antônio do Nascimento Feitosa, Ralf Schwamborn, Tâmara de Almeida e. Silva, and Maria da Glória Gonçalves da Silva-Cunha. "Hydrology, plankton, and corals of the Maracajaú reefs (Northeastern Brazil): an ecosystem under severe thermal stress." Brazilian Archives of Biology and Technology 52, no. 3 (June 2009): 665–78. http://dx.doi.org/10.1590/s1516-89132009000300019.
Full textAbstract:
This study provides baseline information on the hydrological conditions and on the coral and plankton communities at the Maracajaú reef ecosystem (Northeastern Brazil). Studies were performed from February to June 2000, covering the transition from dry to rainy season. In this area, there is an offshore coral reef formation, where corals were observed in loco; the water samples were collected to obtain the hydrological and plankton data. Six scleractinian species were identified. Stable isotope analysis on the carbonate fraction of Favia gravida fragments showed that these corals were under severe thermal stress. Chlorophyll-a varied from 1.1 to 9.3 mg m-3, with higher values during the rainy season. Average zooplankton wet weight biomass were 117.0 (microzooplankton) and 15.7 mg m -3(mesozooplankton). A total of 136 Phytoplankton and 61 zooplankton taxa were identified. Seasonal forcing determined the phyto-micro-and mesozooplankton community structure, rather than the coastal-offshore gradient.
43
Cunning, Ross, Ruth D. Gates, and Peter J. Edmunds. "Using high-throughput sequencing of ITS2 to describe Symbiodinium metacommunities in St. John, US Virgin Islands." PeerJ 5 (June 21, 2017): e3472. http://dx.doi.org/10.7717/peerj.3472.
Full textAbstract:
Symbiotic microalgae (Symbiodinium spp.) strongly influence the performance and stress-tolerance of their coral hosts, making the analysis of Symbiodinium communities in corals (and metacommunities on reefs) advantageous for many aspects of coral reef research. High-throughput sequencing of ITS2 nrDNA offers unprecedented scale in describing these communities, yet high intragenomic variability at this locus complicates the resolution of biologically meaningful diversity. Here, we demonstrate that generating operational taxonomic units by clustering ITS2 sequences at 97% similarity within, but not across, samples collapses sequence diversity that is more likely to be intragenomic, while preserving diversity that is more likely interspecific. We utilize this ‘within-sample clustering’ to analyze Symbiodinium from ten host taxa on shallow reefs on the north and south shores of St. John, US Virgin Islands. While Symbiodinium communities did not differ between shores, metacommunity network analysis of host-symbiont associations revealed Symbiodinium lineages occupying ‘dominant’ and ‘background’ niches, and coral hosts that are more ‘flexible’ or ‘specific’ in their associations with Symbiodinium. These methods shed new light on important questions in coral symbiosis ecology, and demonstrate how application-specific bioinformatic pipelines can improve the analysis of metabarcoding data in microbial metacommunity studies.
44
Willkomm, Horst. "Anomalous High 14C Activity Found in Recent Corals from the Philippines." Radiocarbon 28, no. 2A (1986): 486–94. http://dx.doi.org/10.1017/s0033822200007621.
Full textAbstract:
The carbonate skeletons of small living corals collected in Spring 1981 from Cebu Island, the Philippines, had 14C activities up to 147% of recent standard. Similarly high values were found in the carbonate structure of three large coral heads, where the 14C content of six penetrating cores was measured. In these corals the activity of the outer parts grown since 1960 reached values as high as 155% (corrected for δ13C = − 25‰) while the inner part grown from 1860 to 1950 had values of 106 to 110%. The 14C content of corals should be ca 116% due to the atomic bomb effect and 95% before 1955. The samples were taken from the shore, exposed to tidal waters, so that local contamination is improbable. Organic samples collected from the same region showed normal 14C activity.
45
Gil-Agudelo, Diego L., Diana P. Fonseca, Ernesto Weil, Jaime Garzón-Ferreira, and Garriet W. Smith. "Bacterial communities associated with the mucopolysaccharide layers of three coral species affected and unaffected with dark spots disease." Canadian Journal of Microbiology 53, no. 4 (April 2007): 465–71. http://dx.doi.org/10.1139/w07-002.
Full textAbstract:
Dark spots disease (DSD) is a relatively new coral disease that has become one of the most prevalent afflictions in the Caribbean Sea. To partially characterize bacterial communities associated with DSD, carbon utilization patterns of bacterial strains isolated from the surface mucopolysaccharide layers of healthy and DSD-affected Montastraea annularis , Montastraea faveolata , and Siderastrea siderea were compared with each other and with bacterial strains isolated from the water column by using cluster analysis. Differences between healthy and diseased corals were found and were greatest for M. annularis than for the other species. A metabolic group of bacteria similar to Vibrio carchariae was found to be unique to diseased samples. Inoculation experiments on healthy corals did not result in the development of disease signs. However, our results support the hypothesis that stress (in this case disease) alters the normal microbiota in the coral surface mucopolysaccaride layers. Studies are continuing to determine the pathogenic agent(s) responsible for DSD.
46
Permana, Rizki Dimas, Sunarto Sunarto, Syawalludin Alisyahbana Harahap, Indah Riyantini, and Yuwanda Ilham. "Potassium Cyanide (KCN) Content in Coral Reefs and Its Effect on The Abundance of Indicator-Fishes in The Anambas Islands." Journal of Science and Applicative Technology 5, no. 1 (May 28, 2021): 214. http://dx.doi.org/10.35472/jsat.v5i1.381.
Full textAbstract:
The coral reef ecosystem has been continuously degraded in various parts of Indonesia, including the Anambas Islands. This research aimed to discover the content of Potassium Cyanide (KCN) accumulated on corals and the effect on indicator fishes abundance in the Anambas Islands. This research was conducted at 25 observation stations in the Anambas Islands National Marine Protected Area. The potassium cyanide (KCN) content was tested with the principle of titration and distillation. The coral samples used ranged from 10-20 g diluted in 100-200 ml distilled water. The method used to determine the abundance of indicator fish was underwater visual census or UVC, which recorded fish in every station. This research recorded 307 fish individuals from 14 species of the Chaetodontidae family. Potassium Cyanide's content on corals was high ranging from 0,009-0,032 mg/L with an average 0,0205 mg/L. We concluded that there was a negative correlation between the content of Potassium Cyanide (KCN) on corals and indicator fishes abundance, which means the higher the Potassium Cyanide content (KCN) is on corals, the lower the indicator fishes abundance will point out.
47
Keshavmurthy, Shashank, Hwee Sze Tee, Kuo-Wei Kao, Jih-Terng Wang, and Chaolun Allen Chen. "Specificity trumps flexibility—location-based stable associations between Symbiodiniaceae genera and Platygyra verweyi (Scleractinia; Merulinidae)." PeerJ 8 (May 5, 2020): e8791. http://dx.doi.org/10.7717/peerj.8791.
Full textAbstract:
This study monitored symbiont communities bi-monthly in native coral cores used in a reciprocal transplantation of the coral Platygyra verweyi over two years (2014–2016) and samples of mother colonies from three locations with variable thermal regimes; our results show that associating with multiple Symbiodiniaceae genera (Cladocopium spp. and Durusdinium spp.) is not a prerequisite for symbiont shuffling. Platygyra verweyi associates with certain Symbiodiniaceae genera based on location. Results of quantitative real-time PCR indicated small-scale temporal changes in Symbiodiniaceae genera compositions from 2014 to 2016; however, these changes were not enough to invoke shuffling or switching, despite degree heating weeks exceeding 6 °C-weeks in 2014 and 4 °C-weeks in 2015, which usually resulted in substantial coral bleaching. Microsatellite analysis of the P. verweyi host showed no genetic differences among the study locations. Our results suggest that P. verweyi undergoes long-term acclimatization and/or adaptation based on microgeographic and local environmental conditionsby altering its combinations of associated Symbiodiniaceae. Results also suggest that shuffling might not be as common a phenomenon as it has been given credit for; corals thrive through specific associations, and many corals could still be vulnerable to climate change-induced stress, despite being promiscuous or able to associate with rare and background Symbiodiniaceae genera.
48
Wada, Naohisa, Frederic J. Pollock, Bette L. Willis, Tracy Ainsworth, Nobuhiro Mano, and David G. Bourne. "In situvisualization of bacterial populations in coral tissues: pitfalls and solutions." PeerJ 4 (September 20, 2016): e2424. http://dx.doi.org/10.7717/peerj.2424.
Full textAbstract:
In situvisualization of microbial communities within their natural habitats provides a powerful approach to explore complex interactions between microorganisms and their macroscopic hosts. Specifically, the application of fluorescence in situ hybridization (FISH) to simultaneously identify and visualize diverse microbial taxa associated with coral hosts, including symbiotic algae (Symbiodinium), Bacteria, Archaea, Fungi and protists, could help untangle the structure and function of these diverse taxa within the coral holobiont. However, the application of FISH approaches to coral samples is constrained by non-specific binding of targeted rRNA probes to cellular structures within the coral animal tissues (including nematocysts, spirocysts, granular gland cells within the gastrodermis and cnidoglandular bands of mesenterial filaments). This issue, combined with high auto-fluorescence of both host tissues and endosymbiotic dinoflagellates (Symbiodinium), make FISH approaches for analyses of coral tissues challenging. Here we outline the major pitfalls associated with applying FISH to coral samples and describe approaches to overcome these challenges.
49
Tan, Yuen Ting Rachel, Benjamin J. Wainwright, Lutfi Afiq-Rosli, Yin Cheong Aden Ip, Jen Nie Lee, Nhung Thi Hong Nguyen, Stephen B. Pointing, and Danwei Huang. "Endosymbiont diversity and community structure in Porites lutea from Southeast Asia are driven by a suite of environmental variables." Symbiosis 80, no. 3 (April 2020): 269–77. http://dx.doi.org/10.1007/s13199-020-00671-2.
Full textAbstract:
Abstract Many corals depend upon the highly specialised and intricate relationship they form with Symbiodiniaceae algal symbionts. Porites lutea is a massive reef-building coral found throughout Southeast Asia that hosts these endosymbionts obligately. Yet despite the prevalence and importance of P. lutea as one of the most dominant corals here, its associated Symbiodiniaceae communities have not been precisely characterised. In this study, we used high-throughput DNA amplicon sequencing of the nuclear internal transcribed spacer 2 (ITS2) to characterise the diversity, community structure and biogeographic distribution of Symbiodiniaceae in P. lutea throughout Singapore and Peninsular Malaysia. Consistent with previous studies, we found that Cladocopium was the most dominant genus among all samples, and Cladocopium C15 was the most dominant type (or subclade) with 100% occurrence in all samples from every study site. Results also revealed numerous Symbiodiniaceae types associated with P. lutea that were previously undetected in Southeast Asia. Endosymbiont diversity and community variation are driven by a combination of site-specific mean monthly cloud cover and variance in monthly sea surface temperature. This study contributes baseline data toward understanding differences in Symbiodiniaceae assemblages hosted by P. lutea, shedding light on how they might be indicative of particular environmental conditions and coral responses.
50
Rosales, Stephanie M., Christopher Sinigalliano, Maribeth Gidley, Paul R. Jones, and Lewis J. Gramer. "Oceanographic habitat and the coral microbiomes of urban-impacted reefs." PeerJ 7 (September 10, 2019): e7552. http://dx.doi.org/10.7717/peerj.7552.
Full textAbstract:
Coral reefs are in decline worldwide. In response to this habitat loss, there are efforts to grow, outplant, and restore corals in many regions. The physical oceanographic habitat of corals—such as sea temperature, waves, ocean currents, and available light—is spatially heterogeneous. We therefore hypothesize that outplant location may affect microbiomes, and ultimately, coral health and restoration success. We evaluated the influence of the physical oceanographic habitat on microbes in wild Porites astreoides and Siderastrea siderea. Tissue samples were collected at four Florida reefs in March, June, and September of 2015. We estimated oceanographic conditions from moored instruments, diver observations, remote sensing data, and numerical models. We analyzed microbiomes using amplicon 16S rRNA high-throughput sequencing data. We found microbial alpha-diversity negatively correlated with in situ sea temperature (which represented both the annual cycle and upwelling), as well as modeled alongshore currents, in situ sea-level, and modeled tide. Microbial beta-diversity correlated positively with significant wave height and alongshore currents from models, remotely-sensed relative turbidity, and in situ temperature. We found that archaea from the order Marine Group II decrease with increases in significant wave height, suggesting that this taxon may be influenced by waves. Also, during times of high wave activity, the relative abundance of bacteria from the order Flavobacteriales increases, which may be due to resuspension and cross-shelf transport of sediments. We also found that bacteria from the order SAR86 increase in relative abundance with increased temperature, which suggests that this taxon may play a role in the coral microbiome during periods of higher temperature. Overall, we find that physical oceanographic variability correlates with the structure of these coral microbiomes in ways that could be significant to coral health.