http://lod.bco-dmo.org/id/dataset/699904
eng; USA
utf8
dataset
Highest level of data collection, from a common set of sensors or instrumentation, usually within the same research project
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
2017-05-15
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
Bulk and AA d15N values for ala, glu, and phe from phytoplantkon and grazers grown in lab chemostats
2017-05-17
publication
2017-05-17
revision
BCO-DMO Linked Data URI
2017-05-17
creation
http://lod.bco-dmo.org/id/dataset/699904
Michael R. Landry
University of California-San Diego Scripps
principalInvestigator
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
publisher
Cite this dataset as: Landry, M. R. (2017) Bulk and AA d15N values for ala, glu, and phe from phytoplantkon and grazers grown in lab chemostats. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 17 May 2017) Version Date 2017-05-17 [if applicable, indicate subset used]. http://lod.bco-dmo.org/id/dataset/699904 [access date]
Phytoplankton and grazers grown in lab chemostats Dataset Description: <p>Bulk and AA d15N values for ala, glu, and phe from phytoplantkon and grazers grown in lab chemostats. These data were also published in Table&nbsp;2&nbsp;of:<br />
Décima, M., M. R. Landry, C. J. Bradley, and M. L. Fogel. 2017. Alanine d<sup>15</sup>N trophic fractionation in heterotrophic protists Limnol. Oceanogr., doi:<a href="http://dx.doi.org/10.1002/lno.10567" target="_blank">10.1002/lno.10567</a></p>
<p>The details of the experimental conditions were published in Table 1 of the above publicaiton, and are also <a href="http://dmoserv3.whoi.edu/data_docs/CSIA-AA_Mesozoo/Experimental_conditions.pdf" target="_blank">available in PDF</a>.</p> Methods and Sampling: <p>Trophic changes in d<sup>15</sup>N of AAs from phytoplankton to protistan and metazoan plankton consumers were examined in six chemostat set-ups, including five two-stage experiments and one 3-stage experiment (Décima et al. 2017).</p>
<p>All experiments were conducted in a temperature-controlled room (16 or 18 degrees Celsius) with the algal prey in 2.2-L stage 1 reactors (dilution rate = 0.5 d<sup>-1</sup>) receiving continuous nutrient input from a 20-L reservoir under continuous light (~120 umol photon m<sup>-2</sup> s<sup>-1</sup>).&nbsp; Seawater collected from the Scripps pier (La Jolla, CA) was autoclaved and filtered for all media preparations, using f/2 Guillard concentrations for all nutrients except NO<sup>-</sup><sub>3</sub> or PO<sup>3-&nbsp;</sup><sub>4</sub>, which were varied to produce conditions of N- (Exps. 1 and 4-6) or P-limitation (Exps. 2), while Exp. 3 had no imposed limitation. Flow between the nutrient reservoir and the chemostat culture reactors was continuously pumped through platinum-cured silicone tubes using a Masterflex L/S model 7519-05 peristaltic pump equipped with individually adjustable cassettes for each tube.&nbsp;</p>
<p>For the two-stage experiments, consumers in the stage 2 reactors were grown on the phytoplankton from stage 1 outflow under continuous light or continuous dark conditions to either allow (light) or suppress (dark) phytoplankton uptake of the nutrients regenerated by consumer excretion.&nbsp; The reactors were monitored daily for 12-15 days to ensure constant conditions, thus minimizing predator: prey isotopic mismatch, and samples were taken for cell abundances and biovolumes using an Elzone counter and epifluorescence microscopy.&nbsp; Samples for CSIA-AA were collected at the end of the experiments on pre-combusted 47-mm GFF filters, stored at -80 C, and dried at 60 C for at least 24 h before analyses.&nbsp;</p>
<p>For the 3 stage experiment, the second and third stage reactors had 3.6 L volumes.&nbsp;In the third reactor, metazoan consumers were grown on protistan zooplankton flowing from the second reactor, in turn growing on phytoplankton from the first reactor.&nbsp;Experiments were conducted for 14 days, after which the first and second stages were harvested by filtering the contents onto pre-combusted 47-mm GFFs. Metazoan consumers and &lt;200-um particles in the third-stage reactor were collected as above.</p>
<p>Samples were hydrolyzed and purified AAs derivitized according to established protocols (Popp et al. 2007; Hannides et al. 2009; Décima et al. 2017).&nbsp; All samples were injected (splitless injector) onto a <em>forte</em> BPx5 capillary column (60 m x 0.32 mm x 1.0-um film thickness) at an injector temperature of 250 C with a constant helium flow rate of 1.4 ml min<sup>–1</sup>.&nbsp; The column was initially held at 50 C for 2 min and then increased to 125 C at a rate of 15 C per min.&nbsp;Once at 125 C, the temperature was increased at a rate of 3 C per min to 160 C and then to 190 C at a rate of 4 C per min.&nbsp;The final temperature of 300 C was reached by ramping to 275 C at 6 C per min and then 15 C per min afterward.&nbsp;Samples were analyzed in triplicate and normalized to the known δ<sup>15</sup>N values of a suite of 14 AAs analyzed before and after each set of 3 samples.&nbsp;&nbsp;</p>
<p>References:<br />
Décima, M., M. R. Landry, C. J. Bradley, and M. L. Fogel. 2017. Alanine d<sup>15</sup>N trophic fractionation in heterotrophic protists Limnol. Oceanogr., doi:<a href="http://dx.doi.org/10.1002/lno.10567" target="_blank">10.1002/lno.10567</a></p>
<p>Gutiérrez-Rodríguez, A., Décima, M., Popp, B. N., and Landry, M. R. 2014. Isotopic invisibility of protozoan trophic steps in marine food webs. Limnol. Oceanogr. 59: 1590-1598.</p>
<p>Hannides, C. C. S., B. N. Popp, M. R. Landry, and B. S. Graham. 2009. Quantification of zooplankton trophic position in the North Pacific Subtropical Gyre using stable nitrogen isotopes. Limnol. Oceanogr. 54:<strong> </strong>50-61.</p>
<p>Landry, M.R. and M.R. Décima. 2017. Protistan microzooplankton and the trophic position of tuna:&nbsp; Quantifying the trophic link between micro- and mesozooplankton in marine food webs. ICES J. Mar. Sci. doi:<a href="http://dx.doi.org/10.1093/icesjms/fsx006" target="_blank">10.1093/icesjms/fsx006</a></p>
<p>Popp, B. N., B. S. Graham, R. J. Olson, C. C. S. Hannides, M. J. Lott, G. A. Lopez-Ibarra, F. Galvan-Magana, and B. Fry. 2007. Insight into the trophic ecology of yellowfin tuna, <em>Thunnus albacares</em>, from compound-specific nitrogen isotope analysis of proteinaceous amino acids, p. 173-190. <em>In </em>T. E. Dawson and R. T. W. Siegwolf [eds.], Stable isotopes as indicators of ecological change. Terrestrial Ecology Series. Elsevier Academic Press.</p>
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1260055 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1260055
completed
Michael R. Landry
University of California-San Diego Scripps
858-534-4702
9500 Gilman Drive Mail Code: 0227
La Jolla
CA
92093-0227
USA
mlandry@ucsd.edu
pointOfContact
asNeeded
Dataset Version: 17 May 2017
Unknown
experiment
organism
stage
bulk
bulk_std
Ala1
Glu1
Phe1
Ala1_std
Glu1_std
Phe1_std
Ala2
Glu2
Phe2
Ala2_std
Glu2_std
Phe2_std
epifluorescence microscopy
Trace GC gas chromatograph, GC 1310 gas chromatograph
Delta V Plus
Elzone counter
theme
None, User defined
experiment id
taxon
stage
d15N measured in biota
standard deviation
featureType
BCO-DMO Standard Parameters
Fluorescence Microscope
Gas Chromatograph
Mass Spectrometer
Particle Size Analyzer
instrument
BCO-DMO Standard Instruments
otherRestrictions
otherRestrictions
Access Constraints: none. Use Constraints: Please follow guidelines at: http://www.bco-dmo.org/terms-use Distribution liability: Under no circumstances shall BCO-DMO be liable for any direct, incidental, special, consequential, indirect, or punitive damages that result from the use of, or the inability to use, the materials in this data submission. If you are dissatisfied with any materials in this data submission your sole and exclusive remedy is to discontinue use.
Resolving the trophic connection between protistan grazers and mesozooplankton in marine food webs using amino acid-specific stable isotope analyses
https://osprey.bco-dmo.org/project/556514
Resolving the trophic connection between protistan grazers and mesozooplankton in marine food webs using amino acid-specific stable isotope analyses
<p><em>Description from NSF award abstract:</em><br />
Energy dissipation and elemental cycling by protistan consumers in lower trophic levels of ocean food webs are of sufficient magnitude, based on global mean measures of the amount of primary production consumed, to strongly alter the efficiencies of material transfers to higher-level consumers and to export. We presently know very little about these microbial food web steps, how they vary regionally or temporally, or how they might be altered by climate change. Compound Specific Isotope Analysis of Amino Acids (CSIA-AA) offers an approach for advancing our understanding of microbial food web structure and trophic fluxes based on the trophic positions (TP) of mesozooplankton as temporal integrators of the fluxes from direct feeding on phytoplankton and indirect transfers via protistan microzooplankton. Preliminary laboratory experiments to test this idea have demonstrated that the standard application of the method, using labeled phenylalanine as the representative source AA for the primary producer baseline and labeled glutamic acid as the indicator AA for trophic enrichment, does not produce a measureable trophic-step signal for protistan grazers. However, the results have also shown that an alternative high-turnover AA, alanine, strongly enriches in protistan as well as metazoan consumers, and leads to substantially higher TP estimates of mesozooplankton in field-collected specimens than that based on labeled glutamic acid.</p>
<p>This research project will test the hypothesis that labeled alanine provides a quantifiable and consistent index of trophic enrichment for protistan steps in marine food webs. The research will involve three major elements. First, controlled laboratory experiments will be conducted with chemostat systems to compare 15N enrichments of alanine to other AAs for a representative suite of ciliate and flagellate grazers feeding on phytoplankton, and to evaluate the two-step enrichment from phytoplankton via a protistan grazer to a suspension-feeding copepod. Second, field-collected mesozooplankton from four distinct ecological regions of the Pacific Ocean will be analyzed by CSIA-AA to test the transfer of alanine enrichment through a metazoan trophic step (comparing suspension feeding species to primary carnivores) and to assess how the TP index differs with trophic structure over a broad range of ecological conditions. Last, CSIA-AA assessments of TP for size-structured zooplankton will be integrated into inverse models of nitrogen flows in the four regions (equatorial Pacific, subtropical North Pacific, California Current and Costa Rica Dome) as a major constraint for resolving and comparing fluxes through the microbial food web over the range of ecological conditions. A properly calibrated CSIA-AA assessment of mesozooplankton trophic position will provide a new and valuable approach for regional intercomparisons of lower-level food web structure, for assessing temporal and spatial trends in climate change, for ocean ecosystem model validation, and for better understanding of lower food-web energetic constraints on ocean fisheries.</p>
CSIA-AA Mesozooplankton TP
largerWorkCitation
project
eng; USA
oceans
2017-05-17
California Current, eastern Pacific Ocean
0
BCO-DMO catalogue of parameters from Bulk and AA d15N values for ala, glu, and phe from phytoplantkon and grazers grown in lab chemostats
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
http://lod.bco-dmo.org/id/dataset-parameter/700201.rdf
Name: experiment
Units: unitless
Description: <p>Experiment number. See <a href="<a href="http://dmoserv3.whoi.edu/data_docs/CSIA-AA_Mesozoo/Experimental_conditions.pdf"">http://dmoserv3.whoi.edu/data_docs/CSIA-AA_Mesozoo/Experimental_conditio...</a> target="_blank">details on experimental conditions</a> (PDF)</p>
http://lod.bco-dmo.org/id/dataset-parameter/700202.rdf
Name: organism
Units: unitless
Description: <p>Name of the organism</p>
http://lod.bco-dmo.org/id/dataset-parameter/700203.rdf
Name: stage
Units: unitless
Description: <p>Stage of the experiment</p>
http://lod.bco-dmo.org/id/dataset-parameter/700204.rdf
Name: bulk
Units: per mil (‰)
Description: <p>bulk material d15N</p>
http://lod.bco-dmo.org/id/dataset-parameter/700205.rdf
Name: bulk_std
Units: per mil (‰)
Description: <p>Standard deviation (of 2 replicates) of bulk</p>
http://lod.bco-dmo.org/id/dataset-parameter/700206.rdf
Name: Ala1
Units: per mil (‰)
Description: <p>Alanine d15N of replicate 1</p>
http://lod.bco-dmo.org/id/dataset-parameter/700207.rdf
Name: Glu1
Units: per mil (‰)
Description: <p>Glutamic acid d15N of replicate 1</p>
http://lod.bco-dmo.org/id/dataset-parameter/700208.rdf
Name: Phe1
Units: per mil (‰)
Description: <p>Phenylalanine d15N of replicate 1</p>
http://lod.bco-dmo.org/id/dataset-parameter/700209.rdf
Name: Ala1_std
Units: per mil (‰)
Description: <p>Standard deviation (of 3 machine injections) of Ala1</p>
http://lod.bco-dmo.org/id/dataset-parameter/700210.rdf
Name: Glu1_std
Units: per mil (‰)
Description: <p>Standard deviation (of 3 machine injections) of Glu1</p>
http://lod.bco-dmo.org/id/dataset-parameter/700211.rdf
Name: Phe1_std
Units: per mil (‰)
Description: <p>Standard deviation (of 3 machine injections) of Phe1</p>
http://lod.bco-dmo.org/id/dataset-parameter/700212.rdf
Name: Ala2
Units: per mil (‰)
Description: <p>Alanine d15N of replicate 2</p>
http://lod.bco-dmo.org/id/dataset-parameter/700213.rdf
Name: Glu2
Units: per mil (‰)
Description: <p>Glutamic acid d15N of replicate 2</p>
http://lod.bco-dmo.org/id/dataset-parameter/700214.rdf
Name: Phe2
Units: per mil (‰)
Description: <p>Phenylalanine d15N of replicate 2</p>
http://lod.bco-dmo.org/id/dataset-parameter/700215.rdf
Name: Ala2_std
Units: per mil (‰)
Description: <p>Standard deviation (of 3 machine injections) of Ala2</p>
http://lod.bco-dmo.org/id/dataset-parameter/700216.rdf
Name: Glu2_std
Units: per mil (‰)
Description: <p>Standard deviation (of 3 machine injections) of Glu2</p>
http://lod.bco-dmo.org/id/dataset-parameter/700217.rdf
Name: Phe2_std
Units: per mil (‰)
Description: <p>Standard deviation (of 3 machine injections) of Phe2</p>
GB/NERC/BODC > British Oceanographic Data Centre, Natural Environment Research Council, United Kingdom
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
1538
https://datadocs.bco-dmo.org/file/7DDMmLpcEPkJQw/AA_d15N.csv
AA_d15N.csv
Primary data file for dataset ID 699904
download
https://osprey.bco-dmo.org/dataset/699904/data/download
download
onLine
dataset
<p>Trophic changes in d<sup>15</sup>N of AAs from phytoplankton to protistan and metazoan plankton consumers were examined in six chemostat set-ups, including five two-stage experiments and one 3-stage experiment (Décima et al. 2017).</p>
<p>All experiments were conducted in a temperature-controlled room (16 or 18 degrees Celsius) with the algal prey in 2.2-L stage 1 reactors (dilution rate = 0.5 d<sup>-1</sup>) receiving continuous nutrient input from a 20-L reservoir under continuous light (~120 umol photon m<sup>-2</sup> s<sup>-1</sup>).&nbsp; Seawater collected from the Scripps pier (La Jolla, CA) was autoclaved and filtered for all media preparations, using f/2 Guillard concentrations for all nutrients except NO<sup>-</sup><sub>3</sub> or PO<sup>3-&nbsp;</sup><sub>4</sub>, which were varied to produce conditions of N- (Exps. 1 and 4-6) or P-limitation (Exps. 2), while Exp. 3 had no imposed limitation. Flow between the nutrient reservoir and the chemostat culture reactors was continuously pumped through platinum-cured silicone tubes using a Masterflex L/S model 7519-05 peristaltic pump equipped with individually adjustable cassettes for each tube.&nbsp;</p>
<p>For the two-stage experiments, consumers in the stage 2 reactors were grown on the phytoplankton from stage 1 outflow under continuous light or continuous dark conditions to either allow (light) or suppress (dark) phytoplankton uptake of the nutrients regenerated by consumer excretion.&nbsp; The reactors were monitored daily for 12-15 days to ensure constant conditions, thus minimizing predator: prey isotopic mismatch, and samples were taken for cell abundances and biovolumes using an Elzone counter and epifluorescence microscopy.&nbsp; Samples for CSIA-AA were collected at the end of the experiments on pre-combusted 47-mm GFF filters, stored at -80 C, and dried at 60 C for at least 24 h before analyses.&nbsp;</p>
<p>For the 3 stage experiment, the second and third stage reactors had 3.6 L volumes.&nbsp;In the third reactor, metazoan consumers were grown on protistan zooplankton flowing from the second reactor, in turn growing on phytoplankton from the first reactor.&nbsp;Experiments were conducted for 14 days, after which the first and second stages were harvested by filtering the contents onto pre-combusted 47-mm GFFs. Metazoan consumers and &lt;200-um particles in the third-stage reactor were collected as above.</p>
<p>Samples were hydrolyzed and purified AAs derivitized according to established protocols (Popp et al. 2007; Hannides et al. 2009; Décima et al. 2017).&nbsp; All samples were injected (splitless injector) onto a <em>forte</em> BPx5 capillary column (60 m x 0.32 mm x 1.0-um film thickness) at an injector temperature of 250 C with a constant helium flow rate of 1.4 ml min<sup>–1</sup>.&nbsp; The column was initially held at 50 C for 2 min and then increased to 125 C at a rate of 15 C per min.&nbsp;Once at 125 C, the temperature was increased at a rate of 3 C per min to 160 C and then to 190 C at a rate of 4 C per min.&nbsp;The final temperature of 300 C was reached by ramping to 275 C at 6 C per min and then 15 C per min afterward.&nbsp;Samples were analyzed in triplicate and normalized to the known δ<sup>15</sup>N values of a suite of 14 AAs analyzed before and after each set of 3 samples.&nbsp;&nbsp;</p>
<p>References:<br />
Décima, M., M. R. Landry, C. J. Bradley, and M. L. Fogel. 2017. Alanine d<sup>15</sup>N trophic fractionation in heterotrophic protists Limnol. Oceanogr., doi:<a href="http://dx.doi.org/10.1002/lno.10567" target="_blank">10.1002/lno.10567</a></p>
<p>Gutiérrez-Rodríguez, A., Décima, M., Popp, B. N., and Landry, M. R. 2014. Isotopic invisibility of protozoan trophic steps in marine food webs. Limnol. Oceanogr. 59: 1590-1598.</p>
<p>Hannides, C. C. S., B. N. Popp, M. R. Landry, and B. S. Graham. 2009. Quantification of zooplankton trophic position in the North Pacific Subtropical Gyre using stable nitrogen isotopes. Limnol. Oceanogr. 54:<strong> </strong>50-61.</p>
<p>Landry, M.R. and M.R. Décima. 2017. Protistan microzooplankton and the trophic position of tuna:&nbsp; Quantifying the trophic link between micro- and mesozooplankton in marine food webs. ICES J. Mar. Sci. doi:<a href="http://dx.doi.org/10.1093/icesjms/fsx006" target="_blank">10.1093/icesjms/fsx006</a></p>
<p>Popp, B. N., B. S. Graham, R. J. Olson, C. C. S. Hannides, M. J. Lott, G. A. Lopez-Ibarra, F. Galvan-Magana, and B. Fry. 2007. Insight into the trophic ecology of yellowfin tuna, <em>Thunnus albacares</em>, from compound-specific nitrogen isotope analysis of proteinaceous amino acids, p. 173-190. <em>In </em>T. E. Dawson and R. T. W. Siegwolf [eds.], Stable isotopes as indicators of ecological change. Terrestrial Ecology Series. Elsevier Academic Press.</p>
Specified by the Principal Investigator(s)
<p>Amino acid data were processed using R software to correct sample values using a standard curve of known versus measured δ<sup>15</sup>N values.&nbsp;The standard deviations of measured δ<sup>15</sup>N values of standard AAs ranged from 0.1 to 1.7‰.&nbsp; Statistical tests using AA data were processed using Matlab 2013a.
</p>
<p>BCO-DMO Processing:<br />
- modified parameter names to conform with BCO-DMO naming conventions;<br />
- replaced spaces with underscores in organism and stage columns;<br />
- replaced missing data with 'nd';<br />
- converted Table 1 to PDF.</p>
Specified by the Principal Investigator(s)
asNeeded
7.x-1.1
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
epifluorescence microscopy
epifluorescence microscopy
PI Supplied Instrument Name: epifluorescence microscopy PI Supplied Instrument Description:The reactors were monitored daily for 12-15 days to ensure constant conditions, thus minimizing predator: prey isotopic mismatch, and samples were taken for cell abundances and biovolumes using an Elzone counter and epifluorescence microscopy. Instrument Name: Fluorescence Microscope Instrument Short Name: Instrument Description: Instruments that generate enlarged images of samples using the phenomena of fluorescence and phosphorescence instead of, or in addition to, reflection and absorption of visible light. Includes conventional and inverted instruments. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/LAB06/
Trace GC gas chromatograph, GC 1310 gas chromatograph
Trace GC gas chromatograph, GC 1310 gas chromatograph
PI Supplied Instrument Name: Trace GC gas chromatograph, GC 1310 gas chromatograph PI Supplied Instrument Description:For experiments 1-4, we used a Delta V Plus mass spectrometer interfaced with a Trace GC gas chromatograph through a GC-C III combustion furnace (980C), reduction furnace (650C), and liquid nitrogen cold trap as described in Hannides et al. (2009).
For experiments 5-6 we used a Delta V Plus mass spectrometer (Thermo Scientific) interfaced through a Conflo IV to a GC 1310 gas chromatograph coupled to a GC Isolink combustion-reduction furnace (1000C) and liquid nitrogen cold trap.
Instrument Name: Gas Chromatograph Instrument Short Name:Gas Chromatograph Instrument Description: Instrument separating gases, volatile substances, or substances dissolved in a volatile solvent by transporting an inert gas through a column packed with a sorbent to a detector for assay. (from SeaDataNet, BODC) Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/LAB02/
Delta V Plus
Delta V Plus
PI Supplied Instrument Name: Delta V Plus PI Supplied Instrument Description:For experiments 1-4, we used a Delta V Plus mass spectrometer interfaced with a Trace GC gas chromatograph through a GC-C III combustion furnace (980C), reduction furnace (650C), and liquid nitrogen cold trap as described in Hannides et al. (2009).
For experiments 5-6 we used a Delta V Plus mass spectrometer (Thermo Scientific) interfaced through a Conflo IV to a GC 1310 gas chromatograph coupled to a GC Isolink combustion-reduction furnace (1000C) and liquid nitrogen cold trap.
Instrument Name: Mass Spectrometer Instrument Short Name:Mass Spec Instrument Description: General term for instruments used to measure the mass-to-charge ratio of ions; generally used to find the composition of a sample by generating a mass spectrum representing the masses of sample components. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/LAB16/
Elzone counter
Elzone counter
PI Supplied Instrument Name: Elzone counter PI Supplied Instrument Description:The reactors were monitored daily for 12-15 days to ensure constant conditions, thus minimizing predator: prey isotopic mismatch, and samples were taken for cell abundances and biovolumes using an Elzone counter and epifluorescence microscopy. Instrument Name: Particle Size Analyzer Instrument Short Name: Instrument Description: Particle size analysis, particle size measurement, or simply particle sizing is the collective name of the technical procedures, or laboratory techniques which determines the size range, and/or the average, or mean size of the particles in a powder or liquid sample.