Accessing BCO-DMO data
Brought to you by BCO-DMO
|
|
BCO-DMO ERDDAP
Accessing BCO-DMO data |
log in
Brought to you by BCO-DMO |
| griddap | Subset | tabledap | Make A Graph | wms | files | Accessible | Title | Summary | FGDC | ISO 19115 | Info | Background Info | RSS | Institution | Dataset ID | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_738772 | https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_738772.graph | https://erddap.bco-dmo.org/erddap/files/bcodmo_dataset_738772/ | public | [coccolithophore-associated biopolymers for radionuclides] - Coccolithophore-associated organic biopolymers for fractionating particle-reactive radionuclides (234Th, 233Pa, 210Pb, 210Po, and 7Be) (Biopolymers as carrier phases for selected natural radionuclides (of Th, Pa, Pb, Po, Be) in diatoms and coccolithophores) | Laboratory incubation experiments using the coccolithophore Emiliania huxleyi were conducted in the presence of 234Th, 233Pa, 210Pb, 210Po, and 7Be to differentiate radionuclide uptake to the CaCO3 coccosphere from coccolithophore-associated biopolymers.\n\ncdm_data_type = Other\nVARIABLES:\nBiopolymer_Fraction (unitless)\nTh234_Activity (unitless)\nPa233_Activity (unitless)\nPb210_Activity (unitless)\nPo210_Activity (unitless)\nBe7_Activity (unitless)\nProtein_Amount (microMole Carbon (uM-C))\nTCHO_Amount (microMole Carbon (uM-C))\nURA_Amount (microMole Carbon (uM-C))\nProtein_C_TCHO_C (unitless)\nURA_pcnt_TCHO (unitless)\n | https://erddap.bco-dmo.org/erddap/metadata/iso19115/xml/bcodmo_dataset_738772_iso19115.xml | https://erddap.bco-dmo.org/erddap/info/bcodmo_dataset_738772/index.htmlTable | https://www.bco-dmo.org/dataset/738772
| https://erddap.bco-dmo.org/erddap/rss/bcodmo_dataset_738772.rss | https://erddap.bco-dmo.org/erddap/subscriptions/add.html?datasetID=bcodmo_dataset_738772&showErrors=false&email= | BCO-DMO | bcodmo_dataset_738772 | ||||
| https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_764480 | https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_764480.graph | https://erddap.bco-dmo.org/erddap/files/bcodmo_dataset_764480/ | public | [Fe, Pu partitioning and organic biopolymers] - Partitioning of iron and plutonium in exopolymeric substances and intracellular biopolymers: a comparison study between the coccolithophore Emiliania huxleyi and the diatom Skeletonema costatum (Biopolymers as carrier phases for selected natural radionuclides (of Th, Pa, Pb, Po, Be) in diatoms and coccolithophores) | Iron (Fe), a micronutrient for algal growth, and plutonium (Pu), an anthropogenic radionuclide, share some common features. This includes similar oceanic distributions when different input modes are taken into account, as well as their chemical behavior, such as a high affinity to natural organic matter (NOM). The NOM produced by various phytoplankton communities can potentially influence Fe cycling in the ocean, and likely also influence the transport behavior of Pu. We conducted laboratory incubation experiments using the coccolithophore Emiliania huxleyi and the diatom Skeletonema costatum, in the presence of 59Fe and 238Pu as radiotracers, in order to differentiate Fe and Pu uptake by extracellular exopolymeric substances (EPS) and intracellular biopolymers. The Fe and Pu distributions in select organic compound classes including proteins, total carbohydrates (TCHO) and uronic acids (URA) produced by these two types of phytoplankton were compared. Our results indicated that most of the Fe and Pu (>95%) were found concurrently concentrated in E. huxleyi-derived non-attached EPS, while much less (<2%) was present in the intracellular fraction of E. huxleyi. By contrast, in the diatom S. costatum, both Fe and Pu distribution was EPS > intracellular biopolymers > outer cell covering (i.e., frustule). In fact, over 50% of Fe was concentrated in S. costatum-derived attached EPS and intracellular biopolymers. The diatom derived Fe-EPS complexes were more hydrophobic, with stronger tendency to aggregate in seawater. Fe binding to biopolymers in both E. huxleyi and S. costatum cultures was related to URA concentrations, but the overall distribution of URA between these two phytoplankton species was different. Our findings suggest that the presence of URA in S. costatum cellular surface (i.e., attached EPS) and its intracellular fraction could be an indicator for the Fe transport from the surrounding seawater to the diatom cells. However, for the coccolithophore E. huxleyi, Fe appeared not to be efficiently taken up during its growth. Instead, the more hydrophilic non-attached EPS (i.e., low protein/TCHO ratio) produced by E. huxleyi could have stabilized Fe in the colloidal form as Fe-EPS complexes. Similar partitioning behavior of Fe and Pu suggests that Pu isotopes can potentially serve as a tracer for the Fe biogeochemistry in the ocean.\n\ncdm_data_type = Other\nVARIABLES:\ntype (unitless)\nBiopolymer_fraction (unitless)\nCell_type (unitless)\n... (7 more variables)\n | https://erddap.bco-dmo.org/erddap/metadata/iso19115/xml/bcodmo_dataset_764480_iso19115.xml | https://erddap.bco-dmo.org/erddap/info/bcodmo_dataset_764480/index.htmlTable | https://www.bco-dmo.org/dataset/764480
| https://erddap.bco-dmo.org/erddap/rss/bcodmo_dataset_764480.rss | https://erddap.bco-dmo.org/erddap/subscriptions/add.html?datasetID=bcodmo_dataset_764480&showErrors=false&email= | BCO-DMO | bcodmo_dataset_764480 | ||||
| https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_764794.subset | https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_764794 | https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_764794.graph | https://erddap.bco-dmo.org/erddap/files/bcodmo_dataset_764794/ | public | [IEF] - Isoelectric focussing electrophoresis of percent activity of radioisotopes and major constituents incubated in natural colloidal organic matter collected from stations E1, E3, C9, C11 (Biopolymers as carrier phases for selected natural radionuclides (of Th, Pa, Pb, Po, Be) in diatoms and coccolithophores) | Isoelectric focussing electrophoresis of percent activity of radioisotopes and major constituents incubated in natural colloidal organic matter collected from stations E1, E3, C9, C11. To study the binding mechanisms of radionuclides to organic moieties in colloidal organic matter (COM),marine colloids (1 kDa\\u20130.2 \\u03bcm) were isolated by cross-flow ultrafiltration from seawater of the west Pacific Ocean and the northern Gulf of Mexico. For the same purpose, exopolymeric substances (EPS) produced by laboratory cultured diatoms were collected as well. In our study areas, colloidal organic carbon (COC) concentrations ranged from 6.5 to 202 \\u03bcg-C/L in the Pacific Ocean, and were 808 \\u03bcg-C/L in the Gulf of Mexico. The COM compositions (organic carbon, organic nitrogen, proteins, total hydrolysable amino acids, total polysaccharides, uronic acids, hydroxamate siderophores, hydroquinone) were quantified to examine the relationships between partition coefficients (Kc) of five different radionuclides, 234Th, 233Pa, 210Pb, 210Po and 7Be, and concentration ratios to COC of individual chelating biomolecules that could potentially act as a chelating moiety. The range of partition coefficients (Kc, reported as logKc) of radionuclides between water and the different colloidal materials was 5.12 to 5.85 for 234Th, 5.19 to 6.01 for 233Pa, 4.21 to 4.85 for 210Pb, 4.87 to 5.68 for 210Po, and 4.49 to 4.92 for 7Be, similar to values previously reported for lab and field determinations under different particle concentrations. While any relationship obtained between Kc and abundance of specific moieties could not be taken as proving the existence of colloidal organic binding ligands for the different radionuclides, it could suggest possible organic moieties involved in the scavenging of these natural radionuclides. Together with results from isoelectric focusing of radiolabeled COM, we conclude that binding to different biomolecules is nuclide-specific, with colloidal hydroxamate siderophoric moieties being important for the binding of Th and Pa radionuclides. Hydroquinones/ quinone (HQ/Q) facilitated redox and chelation reactions seem to be involved in the binding of Pa and Be. However, the actual mechanisms are not clear. Individual amino acids, proteins, total polysaccharides and uronic acids did not yield significant relationships with logKc values of the different radionuclides. Nonetheless, our results provide new insights into the relative importance of different potential ligand moieties in COM in the binding and possible scavenging of specific radionuclides in the ocean.\n\ncdm_data_type = Other\nVARIABLES:\npH (Sea Water Ph Reported On Total Scale, unitless)\n... (30 more variables)\n | https://erddap.bco-dmo.org/erddap/metadata/iso19115/xml/bcodmo_dataset_764794_iso19115.xml | https://erddap.bco-dmo.org/erddap/info/bcodmo_dataset_764794/index.htmlTable | https://www.bco-dmo.org/dataset/764794
| https://erddap.bco-dmo.org/erddap/rss/bcodmo_dataset_764794.rss | https://erddap.bco-dmo.org/erddap/subscriptions/add.html?datasetID=bcodmo_dataset_764794&showErrors=false&email= | BCO-DMO | bcodmo_dataset_764794 | |||
| https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_764860 | https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_764860.graph | https://erddap.bco-dmo.org/erddap/files/bcodmo_dataset_764860/ | public | [percent_amount] - Percent amount of organic fractions from diatoms that bind with radionuclides (Biopolymers as carrier phases for selected natural radionuclides (of Th, Pa, Pb, Po, Be) in diatoms and coccolithophores) | In order to investigate the importance of biogenic silica associated biopolymers on the scavenging of radionuclides, the diatom Phaeodactylum tricornutum was incubated together with the radionuclides 234Th, 233Pa, 210Pb, and 7Be during their growth phase. Normalized affinity coefficients were determined for the radionuclides bound with different organic compound classes (i.e., proteins, total carbohydrates, uronic acids) in extracellular (nonattached and attached exopolymeric substances), intracellular (ethylene diamine tetraacetic acid and sodium dodecyl sulfate extractable), and frustule embedded biopolymeric fractions (BF). Results indicated that radionuclides were mostly concentrated in frustule BF. Among three measured organic components, Uronic acids showed the strongest affinities to all tested radionuclides. Confirmed by spectrophotometry and two-dimensional heteronuclear single quantum coherence-nuclear magnetic resonance analyses, the frustule BF were mainly composed of carboxyl-rich, aliphatic-phosphoproteins, which were likely responsible for the strong binding of many of the radionuclides. Results from this study provide evidence for selective absorption of radionuclides with different kinds of diatom-associated biopolymers acting in concert rather than as a single compound. This clearly indicates the importance of these diatom-related biopolymers, especially frustule biopolymers, in the scavenging and fractionation of radionuclides used as particle tracers in the ocean.\n\ncdm_data_type = Other\nVARIABLES:\nsubstance (unitless)\nProtein (unitless (percent))\nTCHO (unitless (percent))\nURA (unitless (percent))\n | https://erddap.bco-dmo.org/erddap/metadata/iso19115/xml/bcodmo_dataset_764860_iso19115.xml | https://erddap.bco-dmo.org/erddap/info/bcodmo_dataset_764860/index.htmlTable | https://www.bco-dmo.org/dataset/764860
| https://erddap.bco-dmo.org/erddap/rss/bcodmo_dataset_764860.rss | https://erddap.bco-dmo.org/erddap/subscriptions/add.html?datasetID=bcodmo_dataset_764860&showErrors=false&email= | BCO-DMO | bcodmo_dataset_764860 |