GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 2010-2014  (8)
Document type
Keywords
Years
Year
  • 1
    facet.materialart.
    Unknown
    PANGAEA
    In:  Station Biologique de Roscoff
    Publication Date: 2023-07-11
    Description: Hierarchical clustering. Taxonomic assignment of reads was performed using a preexisting database of SSU rDNA sequences from including XXX reference sequences generated by Sanger sequencing. Experimental amplicons (reads), sorted by abundance, were then concatenated with the reference extracted sequences sorted by decreasing length. All sequences, experimental and referential, were then clustered to 85% identity using the global alignment clustering option of the uclust module from the usearch v4.0 software (Edgar, 2010). Each 85% cluster was then reclustered at a higher stringency level (86%) and so on (87%, 88%,…) in a hierarchical manner up to 100% similarity. Each experimental sequence was then identified by the list of clusters to which it belonged at 85% to 100% levels. This information can be viewed as a matrix with the lines corresponding to different sequences and the columns corresponding to the cluster membership at each clustering level. Taxonomic assignment for a given read was performed by first looking if reference sequences clustered with the experimental sequence at the 100% clustering level. If this was the case, the last common taxonomic name of the reference sequence(s) within the cluster was used to assign the environmental read. If not, the same procedure was applied to clusters from 99% to 85% similarity if necessary, until a cluster was found containing both the experimental read and reference sequence(s), in which case sequences were taxonomically assigned as described above.
    Keywords: BIOACID; Biological Impacts of Ocean Acidification; Class; EPOCA; European Project on Ocean Acidification; Experimental treatment; Experiment day; Family; Fraction; Fraction of sample; Kingdom; Number of sequences; Order; Phylum; Sample ID; Sequence abundance
    Type: Dataset
    Format: text/tab-separated-values, 93578 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    PANGAEA
    In:  Supplement to: Beaufort, Luc; Probert, Ian; de Garidel-Thoron, Thibault; Bendif, E M; Ruiz-Pino, Diana; Metzi, N; Goyet, Catherine; Buchet, Noëlle; Coupel, Pierre; Grelaud, Michaël; Rost, Björn; Rickaby, Rosalind E M; De Vargas, Colomban (2011): Sensitivity of coccolithophores to carbonate chemistry and ocean acidification. Nature, 476, 80-83, https://doi.org/10.1038/nature10295
    Publication Date: 2024-03-15
    Description: About one-third of the carbon dioxide (CO2) released into the atmosphere as a result of human activity has been absorbed by the oceans, where it partitions into the constituent ions of carbonic acid. This leads to ocean acidification, one of the major threats to marine ecosystems and particularly to calcifying organisms such as corals, foraminifera and coccolithophores. Coccolithophores are abundant phytoplankton that are responsible for a large part of modern oceanic carbonate production. Culture experiments investigating the physiological response of coccolithophore calcification to increased CO2 have yielded contradictory results between and even within species. Here we quantified the calcite mass of dominant coccolithophores in the present ocean and over the past forty thousand years, and found a marked pattern of decreasing calcification with increasing partial pressure of CO2 and concomitant decreasing concentrations of CO3. Our analyses revealed that differentially calcified species and morphotypes are distributed in the ocean according to carbonate chemistry. A substantial impact on the marine carbon cycle might be expected upon extrapolation of this correlation to predicted ocean acidification in the future. However, our discovery of a heavily calcified Emiliania huxleyi morphotype in modern waters with low pH highlights the complexity of assemblage-level responses to environmental forcing factors.
    Keywords: Age, dated; Alkalinity, total; Antarctic; Aragonite saturation state; Bicarbonate ion; Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; CTD, Sea-Bird SBE 911plus; Emiliania huxleyi; Emiliania huxleyi, diameter; Emiliania huxleyi, weight; Emiliania huxleyi, weight, standard error; EPOCA; Estimated by measuring brightness in cross-polarized light (birefringence); EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Indian Ocean; LATITUDE; LONGITUDE; Measured and/or detected by SYRACO software; North Atlantic; North Pacific; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; Phytoplankton; Replicates; Salinity; Sample ID; South Atlantic; South Pacific; Temperature, water; Titration potentiometric
    Type: Dataset
    Format: text/tab-separated-values, 16400 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2013-01-01
    Description: Previous genetic studies of extant planktonic foraminifera have provided evidence that the traditional, strictly morphological definition of species in these organisms underestimates their biodiversity. Here, we report the first case where this pattern is reversed. The modern (sub)tropical species plexus Globigerinoides sacculifer is characterized by large morphological variability, which has led to the proliferation of taxonomic names attributed to morphological end-members within the plexus. In order to clarify the taxonomic status of its morphotypes and to investigate the genetic connectivity among its currently partly disjunct (sub)tropical populations, we carried out a global survey of two ribosomal RNA regions (SSU and ITS-1) in all recent morphotypes of the plexus collected throughout (sub)tropical surface waters of the global ocean. Unexpectedly, we find an extremely reduced genetic variation within the plexus and no correlation between genetic and morphological divergence, suggesting taxonomical overinterpretation. The genetic homogeneity within the morphospecies is unexpected, considering its partly disjunct range in the (sub)tropical Atlantic and Indo-Pacific and its old age (early Miocene). A sequence variant in the rapidly evolving ITS-1 region indicates the existence of an exclusively Atlantic haplotype, which suggests an episode of relatively recent (last glacial) isolation, followed by subsequent resumption of unidirectional gene flow from the Indo-Pacific into the Atlantic. This is the first example in planktonic foraminifera where the morphological variability in a morphospecies exceeds its rDNA genetic variability. Such evidence for inconsistent scaling of morphological and genetic diversity in planktonic foraminifera could complicate the interpretation of evolutionary patterns in their fossil record.
    Print ISSN: 0094-8373
    Electronic ISSN: 0094-8373
    Topics: Geosciences
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2019-03-08
    Description: Coccolithophores have influenced the global climate for over 200 million years1. These marine phytoplankton can account for 20 per cent of total carbon fixation in some systems2. They form blooms that can occupy hundreds of thousands of square kilometres and are distinguished by their elegantly sculpted calcium carbonate exoskeletons (coccoliths), rendering themvisible fromspace3.Although coccolithophores export carbon in the form of organic matter and calcite to the sea floor, they also release CO2 in the calcification process. Hence, they have a complex influence on the carbon cycle, driving either CO2 production or uptake, sequestration and export to the deep ocean4. Here we report the first haptophyte reference genome, from the coccolithophore Emiliania huxleyi strain CCMP1516, and sequences from 13 additional isolates. Our analyses reveal a pan genome (core genes plus genes distributed variably between strains) probably supported by an atypical complement of repetitive sequence in the genome. Comparisons across strains demonstrate thatE. huxleyi, which has long been considered a single species, harbours extensive genome variability reflected in different metabolic repertoires. Genome variability within this species complex seems to underpin its capacity both to thrive in habitats ranging from the equator to the subarctic and to form large-scale episodic blooms under a wide variety of environmental conditions.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-07-17
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/zip
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2022-05-25
    Description: © The Author(s), 2013. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Nature 499 (2013): 209–213, doi:10.1038/nature12221.
    Description: Coccolithophores have influenced the global climate for over 200 million years1. These marine phytoplankton can account for 20 per cent of total carbon fixation in some systems2. They form blooms that can occupy hundreds of thousands of square kilometres and are distinguished by their elegantly sculpted calcium carbonate exoskeletons (coccoliths), rendering them visible from space3. Although coccolithophores export carbon in the form of organic matter and calcite to the sea floor, they also release CO2 in the calcification process. Hence, they have a complex influence on the carbon cycle, driving either CO2 production or uptake, sequestration and export to the deep ocean4. Here we report the first haptophyte reference genome, from the coccolithophore Emiliania huxleyi strain CCMP1516, and sequences from 13 additional isolates. Our analyses reveal a pan genome (core genes plus genes distributed variably between strains) probably supported by an atypical complement of repetitive sequence in the genome. Comparisons across strains demonstrate that E. huxleyi, which has long been considered a single species, harbours extensive genome variability reflected in different metabolic repertoires. Genome variability within this species complex seems to underpin its capacity both to thrive in habitats ranging from the equator to the subarctic and to form large-scale episodic blooms under a wide variety of environmental conditions.
    Description: Joint Genome Institute (JGI) contributions were supported by the Office of Science of the US Department of Energy (DOE) under contract no. 7DE-AC02-05CH11231.
    Keywords: Genetic variation
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Format: application/vnd.ms-excel
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-07-17
    Description: This report concerns 3 weeks of open ocean work on board Tara, between the Islands of Maurtius, Reunion, Madagascar, and Mayotte (Fig. 1), from May 7 to May 27, 2010. The goal of the cruise was to sample the planktonic ecosystem from the tropical South Indian Ocean, following the Tara‐Oceans core protocol. The collection included genetic and morphological samples for viruses, giruses, prokaryotes, protists, and metazoa, image data (UVP, flowcam, light microscopy), and physicochemical data/samples from the sampled water column (CTD, Nitrate, Nutrients, Carbonate, Pigments).
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2022-05-26
    Description: Author Posting. © Inter-Research, 2009. This article is posted here by permission of Inter-Research for personal use, not for redistribution. The definitive version was published in Aquatic Microbial Ecology 57 (2009): 279-310, doi:10.3354/ame01340.
    Description: Acquisition of phototrophy is widely distributed in the eukaryotic tree of life and can involve algal endosymbiosis or plastid retention from green or red origins. Species with acquired phototrophy are important components of diversity in aquatic ecosystems, but there are major differences in host and algal taxa involved and in niches of protists with acquired phototrophy in marine and freshwater ecosystems. Organisms that carry out acquired phototrophy are usually mixotrophs, but the degree to which they depend on phototrophy is variable. Evidence suggests that ‘excess carbon’ provided by acquired phototrophy has been important in supporting major evolutionary innovations that are crucial to the current ecological roles of these protists in aquatic ecosystems. Acquired phototrophy occurs primarily among radiolaria, foraminifera, ciliates and dinoflagellates, but is most ecologically important among the first three. Acquired phototrophy in foraminifera and radiolaria is crucial to their contributions to carbonate, silicate, strontium, and carbon flux in subtropical and tropical oceans. Planktonic ciliates with algal kleptoplastids are important in marine and fresh waters, whereas ciliates with green algal endosymbionts are mostly important in freshwaters. The phototrophic ciliate Myrionecta rubra can be a major primary producer in coastal ecosystems. Our knowledge of how acquired phototrophy influences trophic dynamics and biogeochemical cycles is rudimentary; we need to go beyond traditional concepts of ‘plant’ and ‘animal’ functions to progress in our understanding of aquatic microbial ecology. This is a rich area for exploration using a combination of classical and molecular techniques, laboratory and field research, and physiological and ecosystem modeling.
    Description: F.N. and C.dV were supported by a SAD grant SYMFORAD from the Région Bretagne (France) and the BioMarKs project funded by the European ERA-net program BiodivERsA.
    Keywords: Mixotrophy ; Radiolaria ; Foraminifera ; Ciliates ; Dinoflagellates ; Kleptoplastidy ; Karyoklepty ; Endosymbiosis ; Myrionecta rubra
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...