http://lod.bco-dmo.org/id/dataset/925041
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
2024-04-16
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
Results from a laboratory-based investigation into sediment Silicon sorption capacities using standardized clay samples and the radioactive tracer 32Si
2024-04-16
publication
2024-04-16
revision
Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)
2024-04-16
publication
https://doi.org/10.26008/1912/bco-dmo.925041.1
Rebecca A. Pickering
Dauphin Island Sea Lab
principalInvestigator
Jeffrey W. Krause
Dauphin Island Sea Lab
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: Pickering, R. A., Krause, J. W. (2024) Results from a laboratory-based investigation into sediment Silicon sorption capacities using standardized clay samples and the radioactive tracer 32Si. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-04-16 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.925041.1 [access date]
Estuarine Sediment Silicon Sorption Capacities Dataset Description: Methods and Sampling: <p><strong>Source Materials:</strong> The clay standards used were sourced from The Clay Minerals Society Source Clays Repository, and they have well-known chemical compositions. As the materials are a natural clay, these substances are assumed to be slightly impure, e.g. &lt;7% Ti and/or Fe-oxides (Guggenheim, 2001). Montmorillonite and kaolinite were selected due to their environmental relevance, e.g. river plume systems in northern Gulf of Mexico (Grim and Johns, 1954; Pinsak, 1958; Scafe and Kunze, 1971; Sionneau et al., 2008; Ghaisas et al., 2021). SWy-3 is a Na-rich Montmorillonite sourced from Crook County, Wyoming, USA. KGa-2 is a Kaolinite sourced from Warren County, Georgia, USA. Before use, clays were sterilized for 30 minutes inside an Ultraviolet (UV) light box to degrade bacteria and avoid confounding results due to biotic activity. Samples were not ground, chemically- or heat-treated prior to experiments, as these processes are known to increase reactivity by decreasing surface crystallinity. Clays were not size fractionated as little variation in reactivity occurs when separating the &lt; 2 micrometer (μm) size fraction from bulk clays (Siever and Woodford, 1973).</p>
<p><strong>Seawater Collections:</strong> Natural seawater, which contains a complicated blend of dissolved organic and inorganic chemical compounds and species (e.g. macronutrients, trace metals) was used in these experiments as in previous studies (Siever, 1968a; Siever and Woodford, 1973). Bottom water (33 meters) was collected just above the sediment-water interface during Spring 2017 aboard the R/V Pelican (cruise ID: PE17-20) in the northern Gulf of Mexico (Krause et al., 2023); the sample location (28°30’ N, 90°50’ W) is ~150 kilometers west of the main Mississippi River outflow channel (Southwest Pass). The samples in this dataset were collected on May 6, 2017. Water was collected using 10-liter (L) Niskin bottles attached to an Ocean Instruments MC-900 Multi-corer; Niskin bottles were triggered concurrently with the multi-corer release and thus did not capture significant resuspended sediment from the Multi-corer landing. Shortly after recovery, the water was gravity-filtered directly from the Niskin through a 0.2 μm Whatman polycap filter into acid pre-cleaned 10 L carboys for storage (in the dark, room temperature) and future use. In the lab, the salinity (ppt) of the filtered seawater was checked and adjusted with 18.2 MΩ *cm deionized water to either 4 ppt or 32 ppt. The water was then sterilized with a UV Steripen (Adventure Opti Model) for 10 minutes to degrade bacteria and a subsample was analyzed for dSi using a commonly used spectrophotometric molybdate-blue method (e.g. Pickering et al., 2020).</p>
<p><strong>Laboratory Experiments:</strong> Laboratory experiments were conducted from October 1 to October 14, 2018. In the lab, homogenized clay standard samples were weighed and mixed with 250 milliliters (mL) of adjusted seawater to achieve sediment dry-weight solid-to-solution ratios (SSR, grams per liter (g L-1)) of 0.1, 3 and 10; this was done for both clays (SWy-3 and KGa-2) and both salinities (4 ppt and 32 ppt). Procedural blanks were also prepared without the addition of sediment. A Teflon-coated stir bar and stir plate were used to keep the sediment suspended during subsampling. 7 mL of suspended sediment slurry was pipetted into 15 mL polypropylene plug seal centrifuge tubes and 10,000 DPM (167 Bq) of 32Si(OH)4 (104 Bq (µg Si)-1) was then added to each tube. Following the addition of 32Si to each tube, samples were sealed and immediately inverted to ensure the complete mixing of the radioisotope tracer into the slurry. Tubes were placed sideways on a shaker table and incubated in the dark at 15 degrees Celsius (°C) for 144 hours. Samples were vented every 12 hours to ensure oxygenation (i.e. exchange 8-mL ambient air headspace). Triplicate sacrificial sampling of each SSR occurred at the following time points; 0, 12, 24, 48, 72, 96, 120, and 144 hours as described below (i.e., for each clay type and SSR, 24 individual tubes sampled over time).</p>
<p>For each time point, individual samples were partitioned to quantify particulate and dissolved constituents. After mixing thoroughly using a vortex mixer, 3 mL of suspended sediment solution was filtered onto a polycarbonate membrane filter (25-millimeters (mm) diameter - 0.6 μm pore size). This filter was placed on a nylon disk planchette, dried overnight, covered with a mylar film, and both the filter and mylar were secured to the planchette using a nylon ring. Next, the tube was centrifuged for 10 minutes at 1500 x g. Following centrifugation, 2 mL of supernatant was subsampled in 1-mL&nbsp;aliquots. The first 1 mL was placed into a 20 mL plastic liquid scintillation vial. The second 1 mL was analyzed for dSi using a spectrophotometric molybdate-blue method as described above. The remaining 2 mL of solution was frozen for future analysis and contained ~57% of the original sediment, as liquid was removed without sediment from the sample tube for the two 1-mL aliquots. Blanks were treated in the same manner and run in tandem with each sediment (SWy-3, KGa-2) type totaling 48 - 4 ppt and 48 - 32 ppt blanks.</p>
<p><strong>32Si Quantification:</strong> 32Si activity was quantified after the samples were aged into secular equilibrium with 32P, the short-lived (t½ = 14.28 days) and high energy (Emax = 1709 keV) daughter isotope of 32Si (t½ = 144 years, Emax = 227 keV). While the International System derived unit of radioactivity is the becquerel (Bq), we report activity in disintegrations per minute (DPM) (1 Bq = 60 DPM) as it is a functional unit that relates directly to instrument-derived counts per minute (CPM) and counting efficiency. For particulate 32Si, activity was measured using a GM-24 Multicounter (Risø DTU National Laboratory, Denmark) following Krause et al. (2011). For solution 32Si, sample activity was quantified using liquid scintillation counting (LSC). Given the quantity of samples, we chose a more commonly used and inexpensive liquid scintillation cocktail than traditionally used for LSC, e.g. Ultima GoldTM XR (Brzezinski and Phillips, 1997). To the 1 mL solution subsamples, 9 mL of EcoLumeTM (MP Biomedicals LLC, USA) was added, mixed, and total counts in solution were quantified after samples sat 2 hours (to reduce chemoluminescence) using a TriCarb 3110 TR liquid scintillation counter (Perkin Elmer).</p>
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1558957 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1558957
completed
Rebecca A. Pickering
Dauphin Island Sea Lab
+46 46 222 39 78
Department of Geology - Room 328 Sölvegatan 12, 223 62
Lund
Sweden
rebecca.pickering@geol.lu.se
pointOfContact
Jeffrey W. Krause
Dauphin Island Sea Lab
251-861-2141 x2289
101 Bienville Blvd
Dauphin Island
AL
36528
USA
jkrause@disl.edu
pointOfContact
asNeeded
Dataset Version: 1
Unknown
Sample_Number
Sample_Description
Latitude_water_collection
Longitude_water_collection
Depth_water_collection
Sediment_Type_Used
SSR_g_L_1
Salinity_ppt
Time_Elapsed_Hrs
Si32_Initial_isotope_Added_DPM
dSi_in_solution_umol_L_1
Average_dSi_in_solution_umol_L_1
Stdev_dSi_in_solution_umol_L_1
Si32_DPM_in_Solution
Average_32Si_in_solution_DPM
Stdev_32Si_in_solution_DPM
Si32_in_Particles_DPM
Si32_in_Particles_Blank_Corrected_DPM
Average_32Si_in_Particles_Blank_Corrected_DPM
Stdev_32Si_in_Particles_Blank_Corrected_DPM
GM-24 Multicounter (Risø DTU National Laboratory, Denmark)
Ocean Instruments MC-900 Multi-corer
10 L Niskin bottles attached to an Ocean Instruments MC-900 Multi-corer
TriCarb 3110 TR liquid scintillation counter (Perkin Elmer)
Ultraviolet (UV) Light Box
UV Steripen - Adventure Opti Model
theme
None, User defined
sample identification
sample description
latitude
longitude
depth
ratio
salinity
time_elapsed
Silicon
Silicate, Si(OH)4, silicic acid
featureType
BCO-DMO Standard Parameters
GM multicounter
Multi Corer
Niskin bottle
PerkinElmer Tri-Carb 3110TR low activity liquid scintillation analyzer
Ultraviolet Light Sterilization Device
Ultraviolet Light Sterilization Device
instrument
BCO-DMO Standard Instruments
PE17-20
service
Deployment Activity
Northern Gulf of Mexico Shelf
place
Locations
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.
The biotic and abiotic controls on the Silicon cycle in the northern Gulf of Mexico
https://osprey.bco-dmo.org/project/712667
The biotic and abiotic controls on the Silicon cycle in the northern Gulf of Mexico
<p><em>NSF Award Abstract:</em><br />
The Louisiana Shelf system in the northern Gulf of Mexico is fed by the Mississippi River and its many tributaries which contribute large quantities of nutrients from agricultural fertilizer to the region. Input of these nutrients, especially nitrogen, has led to eutrophication. Eutrophication is the process wherein a body of water such as the Louisiana Shelf becomes enriched in dissolved nutrients that increase phytoplankton growth which eventually leads to decreased oxygen levels in bottom waters. This has certainly been observed in this area, and diatoms, a phytoplankton which represents the base of the food chain, have shown variable silicon/nitrogen (Si/N) ratios. Because diatoms create their shells from silicon, their growth is controlled not only by nitrogen inputs but the availability of silicon. Lower Si/N ratios are showing that silicon may be playing an increasingly important role in regulating diatom production in the system. For this reason, a scientist from the University of South Alabama will determine the biogeochemical processes controlling changes in Si/N ratios in the Louisiana Shelf system. One graduate student on their way to a doctorate degree and three undergraduate students will be supported and trained as part of this project. Also, four scholarships for low-income, high school students from Title 1 schools will get to participate in a month-long summer Marine Science course at the Dauphin Island Sea Laboratory and be included in the research project. The study has significant societal benefits given this is an area where $2.4 trillion gross domestic product revenue is tied up in coastal resources. Since diatoms are at the base of the food chain that is the biotic control on said coastal resources, the growth of diatoms in response to eutrophication is important to study.</p>
<p>Eutrophication of the Mississippi River and its tributaries has the potential to alter the biological landscape of the Louisiana Shelf system in the northern Gulf of Mexico by influencing the Si/N ratios below those that are optimal for diatom growth. A scientist from the University of South Alabama believes the observed changes in the Si/N ratio may indicate silicon now plays an important role in regulating diatom production in the system. As such, understanding the biotic and abiotic processes controlling the silicon cycle is crucial because diatoms dominate at the base of the food chain in this highly productive region. The study will focus on following issues: (1) the importance of recycled silicon sources on diatom production; (2) can heavily-silicified diatoms adapt to changing Si/N ratios more effectively than lightly-silicified diatoms; and (3) the role of reverse weathering in sequestering silicon thereby reducing diffusive pore-water transport. To attain these goals, a new analytical approach, the PDMPO method (compound 2-(4-pyridyl)-5-((4-(2-dimethylaminoethylamino-carbamoyl)methoxy)phenyl)oxazole) that quantitatively measures taxa-specific silica production would be used.</p>
CLASiC
largerWorkCitation
project
eng; USA
oceans
Northern Gulf of Mexico Shelf
-90.8167
-90.8167
28.5
28.5
2017-05-06
2018-10-14
Northern Gulf of Mexico, specifically the Louisiana Shelf region dominated by the discharge of the Mississippi River on the western side of the delta
0
BCO-DMO catalogue of parameters from Results from a laboratory-based investigation into sediment Silicon sorption capacities using standardized clay samples and the radioactive tracer 32Si
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/925133.rdf
Name: Sample_Number
Units: unitless
Description: <p>Unique sample ID for each sample incubation</p>
http://lod.bco-dmo.org/id/dataset-parameter/925134.rdf
Name: Sample_Description
Units: unitless
Description: <p>Overall description for solid-to-solution ratio (SSR), salinity, and clay type used for each unique sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/925135.rdf
Name: Latitude_water_collection
Units: decimal degrees
Description: <p>Latitude location in which incubation water was collected; positive values = North</p>
http://lod.bco-dmo.org/id/dataset-parameter/925136.rdf
Name: Longitude_water_collection
Units: decimal degrees
Description: <p>Longitude location in which incubation water was collected; negative values = West</p>
http://lod.bco-dmo.org/id/dataset-parameter/925137.rdf
Name: Depth_water_collection
Units: meters (m)
Description: <p>Depth in which incubation water was collection</p>
http://lod.bco-dmo.org/id/dataset-parameter/925138.rdf
Name: Sediment_Type_Used
Units: unitless
Description: <p>Clay Mineral Society source clay standard type used (KGa-2 or SWy-3)</p>
http://lod.bco-dmo.org/id/dataset-parameter/925139.rdf
Name: SSR_g_L_1
Units: grams per liter (g L-1)
Description: <p>Sediment to solution ratio</p>
http://lod.bco-dmo.org/id/dataset-parameter/925140.rdf
Name: Salinity_ppt
Units: ppt
Description: <p>Corrected salinity used</p>
http://lod.bco-dmo.org/id/dataset-parameter/925141.rdf
Name: Time_Elapsed_Hrs
Units: hours
Description: <p>Time elapsed from starting 32Si isotope addition until stopping the incubation</p>
http://lod.bco-dmo.org/id/dataset-parameter/925142.rdf
Name: Si32_Initial_isotope_Added_DPM
Units: disintegrations per minute (DPM)
Description: <p>Total starting 32Si isotope added to individual sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/925143.rdf
Name: dSi_in_solution_umol_L_1
Units: micromoles per liter (umol L-1)
Description: <p>Final dissolved Si(OH)4 in solution at unique timepoint indicated</p>
http://lod.bco-dmo.org/id/dataset-parameter/925144.rdf
Name: Average_dSi_in_solution_umol_L_1
Units: micromoles per liter (umol L-1)
Description: <p>Average final dissolved Si(OH)4 in solution for 3 sacrificial triplicate timepoints</p>
http://lod.bco-dmo.org/id/dataset-parameter/925145.rdf
Name: Stdev_dSi_in_solution_umol_L_1
Units: micromoles per liter (umol L-1)
Description: <p>Standard deviation of final dissolved Si(OH)4 in solution for 3 sacrificial triplicate timepoints</p>
http://lod.bco-dmo.org/id/dataset-parameter/925146.rdf
Name: Si32_DPM_in_Solution
Units: disintegrations per minute (DPM)
Description: <p>Final DPM of 32Si in solution at unique timepoint indicated</p>
http://lod.bco-dmo.org/id/dataset-parameter/925147.rdf
Name: Average_32Si_in_solution_DPM
Units: disintegrations per minute (DPM)
Description: <p>Average final DPM of 32Si in solution for 3 sacrificial triplicate timepoints</p>
http://lod.bco-dmo.org/id/dataset-parameter/925148.rdf
Name: Stdev_32Si_in_solution_DPM
Units: disintegrations per minute (DPM)
Description: <p>Standard deviation of final DPM of 32Si in solution for 3 sacrificial triplicate timepoints</p>
http://lod.bco-dmo.org/id/dataset-parameter/925149.rdf
Name: Si32_in_Particles_DPM
Units: disintegrations per minute (DPM)
Description: <p>Final DPM of 32Si in sediment particles at unique timepoint indicated</p>
http://lod.bco-dmo.org/id/dataset-parameter/925150.rdf
Name: Si32_in_Particles_Blank_Corrected_DPM
Units: disintegrations per minute (DPM)
Description: <p>Blank corrected (using the average of the 3 blanks for this timepoints) final DPM of 32Si in sediment particles at unique timepoint indicated</p>
http://lod.bco-dmo.org/id/dataset-parameter/925151.rdf
Name: Average_32Si_in_Particles_Blank_Corrected_DPM
Units: disintegrations per minute (DPM)
Description: <p>Blank corrected average final DPM of 32Si in sediment particle for 3 sacrificial triplicate timepoints</p>
http://lod.bco-dmo.org/id/dataset-parameter/925152.rdf
Name: Stdev_32Si_in_Particles_Blank_Corrected_DPM
Units: disintegrations per minute (DPM)
Description: <p>Blank corrected standard deviation final DPM of 32Si in sediment particle for 3 sacrificial triplicate timepoints</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
41850
https://darchive.mblwhoilibrary.org/server/api/core/bitstreams/a4a2db4f-8b35-4bdf-9693-f1d32b51ecab/content
download
https://doi.org/10.26008/1912/bco-dmo.925041.1
download
onLine
dataset
<p><strong>Source Materials:</strong> The clay standards used were sourced from The Clay Minerals Society Source Clays Repository, and they have well-known chemical compositions. As the materials are a natural clay, these substances are assumed to be slightly impure, e.g. &lt;7% Ti and/or Fe-oxides (Guggenheim, 2001). Montmorillonite and kaolinite were selected due to their environmental relevance, e.g. river plume systems in northern Gulf of Mexico (Grim and Johns, 1954; Pinsak, 1958; Scafe and Kunze, 1971; Sionneau et al., 2008; Ghaisas et al., 2021). SWy-3 is a Na-rich Montmorillonite sourced from Crook County, Wyoming, USA. KGa-2 is a Kaolinite sourced from Warren County, Georgia, USA. Before use, clays were sterilized for 30 minutes inside an Ultraviolet (UV) light box to degrade bacteria and avoid confounding results due to biotic activity. Samples were not ground, chemically- or heat-treated prior to experiments, as these processes are known to increase reactivity by decreasing surface crystallinity. Clays were not size fractionated as little variation in reactivity occurs when separating the &lt; 2 micrometer (μm) size fraction from bulk clays (Siever and Woodford, 1973).</p>
<p><strong>Seawater Collections:</strong> Natural seawater, which contains a complicated blend of dissolved organic and inorganic chemical compounds and species (e.g. macronutrients, trace metals) was used in these experiments as in previous studies (Siever, 1968a; Siever and Woodford, 1973). Bottom water (33 meters) was collected just above the sediment-water interface during Spring 2017 aboard the R/V Pelican (cruise ID: PE17-20) in the northern Gulf of Mexico (Krause et al., 2023); the sample location (28°30’ N, 90°50’ W) is ~150 kilometers west of the main Mississippi River outflow channel (Southwest Pass). The samples in this dataset were collected on May 6, 2017. Water was collected using 10-liter (L) Niskin bottles attached to an Ocean Instruments MC-900 Multi-corer; Niskin bottles were triggered concurrently with the multi-corer release and thus did not capture significant resuspended sediment from the Multi-corer landing. Shortly after recovery, the water was gravity-filtered directly from the Niskin through a 0.2 μm Whatman polycap filter into acid pre-cleaned 10 L carboys for storage (in the dark, room temperature) and future use. In the lab, the salinity (ppt) of the filtered seawater was checked and adjusted with 18.2 MΩ *cm deionized water to either 4 ppt or 32 ppt. The water was then sterilized with a UV Steripen (Adventure Opti Model) for 10 minutes to degrade bacteria and a subsample was analyzed for dSi using a commonly used spectrophotometric molybdate-blue method (e.g. Pickering et al., 2020).</p>
<p><strong>Laboratory Experiments:</strong> Laboratory experiments were conducted from October 1 to October 14, 2018. In the lab, homogenized clay standard samples were weighed and mixed with 250 milliliters (mL) of adjusted seawater to achieve sediment dry-weight solid-to-solution ratios (SSR, grams per liter (g L-1)) of 0.1, 3 and 10; this was done for both clays (SWy-3 and KGa-2) and both salinities (4 ppt and 32 ppt). Procedural blanks were also prepared without the addition of sediment. A Teflon-coated stir bar and stir plate were used to keep the sediment suspended during subsampling. 7 mL of suspended sediment slurry was pipetted into 15 mL polypropylene plug seal centrifuge tubes and 10,000 DPM (167 Bq) of 32Si(OH)4 (104 Bq (µg Si)-1) was then added to each tube. Following the addition of 32Si to each tube, samples were sealed and immediately inverted to ensure the complete mixing of the radioisotope tracer into the slurry. Tubes were placed sideways on a shaker table and incubated in the dark at 15 degrees Celsius (°C) for 144 hours. Samples were vented every 12 hours to ensure oxygenation (i.e. exchange 8-mL ambient air headspace). Triplicate sacrificial sampling of each SSR occurred at the following time points; 0, 12, 24, 48, 72, 96, 120, and 144 hours as described below (i.e., for each clay type and SSR, 24 individual tubes sampled over time).</p>
<p>For each time point, individual samples were partitioned to quantify particulate and dissolved constituents. After mixing thoroughly using a vortex mixer, 3 mL of suspended sediment solution was filtered onto a polycarbonate membrane filter (25-millimeters (mm) diameter - 0.6 μm pore size). This filter was placed on a nylon disk planchette, dried overnight, covered with a mylar film, and both the filter and mylar were secured to the planchette using a nylon ring. Next, the tube was centrifuged for 10 minutes at 1500 x g. Following centrifugation, 2 mL of supernatant was subsampled in 1-mL&nbsp;aliquots. The first 1 mL was placed into a 20 mL plastic liquid scintillation vial. The second 1 mL was analyzed for dSi using a spectrophotometric molybdate-blue method as described above. The remaining 2 mL of solution was frozen for future analysis and contained ~57% of the original sediment, as liquid was removed without sediment from the sample tube for the two 1-mL aliquots. Blanks were treated in the same manner and run in tandem with each sediment (SWy-3, KGa-2) type totaling 48 - 4 ppt and 48 - 32 ppt blanks.</p>
<p><strong>32Si Quantification:</strong> 32Si activity was quantified after the samples were aged into secular equilibrium with 32P, the short-lived (t½ = 14.28 days) and high energy (Emax = 1709 keV) daughter isotope of 32Si (t½ = 144 years, Emax = 227 keV). While the International System derived unit of radioactivity is the becquerel (Bq), we report activity in disintegrations per minute (DPM) (1 Bq = 60 DPM) as it is a functional unit that relates directly to instrument-derived counts per minute (CPM) and counting efficiency. For particulate 32Si, activity was measured using a GM-24 Multicounter (Risø DTU National Laboratory, Denmark) following Krause et al. (2011). For solution 32Si, sample activity was quantified using liquid scintillation counting (LSC). Given the quantity of samples, we chose a more commonly used and inexpensive liquid scintillation cocktail than traditionally used for LSC, e.g. Ultima GoldTM XR (Brzezinski and Phillips, 1997). To the 1 mL solution subsamples, 9 mL of EcoLumeTM (MP Biomedicals LLC, USA) was added, mixed, and total counts in solution were quantified after samples sat 2 hours (to reduce chemoluminescence) using a TriCarb 3110 TR liquid scintillation counter (Perkin Elmer).</p>
Specified by the Principal Investigator(s)
<p>Dixon's Q-Test was used to identify outliers among triplicate replicates (Dean and Dixon, 1951), and these values were removed from the dataset, (32Si particulates; n = 8 out of 288 samples, 32Si solution; n = 6 out of 288 samples). Two factor ANOVA with replication on Microsoft Excel was used to examine differences among treatments; an alpha value of 0.05 was assigned a priori. An F value represents how much the variability between averages, exceeds those expected, while a FCritical value determines if the averages between two populations are significant.</p>
Specified by the Principal Investigator(s)
- Imported original file "Pickering et al_Data _Overall_Summary.xlsx" into the BCO-DMO system.
- Renamed fields to comply with BCO-DMO naming conventions.
- Converted latitude and longitude from degrees and decimal minutes to decimal degrees, and rounded values to 5 decimal places.
- Saved the final file as "925041_v1_estuarine_sediment_si_sorption_capacities.csv".
Specified by BCO-DMO Data Managers
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
GM-24 Multicounter (Risø DTU National Laboratory, Denmark)
GM-24 Multicounter (Risø DTU National Laboratory, Denmark)
PI Supplied Instrument Name: GM-24 Multicounter (Risø DTU National Laboratory, Denmark) Instrument Name: GM multicounter Instrument Short Name: Instrument Description: A gas flow multicounter (GM multicounter) is used for counting low-level beta doses. GM multicounters can be used for gas proportional counting of 32Si to 32P. For more information about GM multicounter usage see Krause et. al. 2011.
Ocean Instruments MC-900 Multi-corer
Ocean Instruments MC-900 Multi-corer
PI Supplied Instrument Name: Ocean Instruments MC-900 Multi-corer Instrument Name: Multi Corer Instrument Short Name:Multi Corer Instrument Description: The Multi Corer is a benthic coring device used to collect multiple, simultaneous, undisturbed sediment/water samples from the seafloor. Multiple coring tubes with varying sampling capacity depending on tube dimensions are mounted in a frame designed to sample the deep ocean seafloor. For more information, see Barnett et al. (1984) in Oceanologica Acta, 7, pp. 399-408. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/51/
10 L Niskin bottles attached to an Ocean Instruments MC-900 Multi-corer
10 L Niskin bottles attached to an Ocean Instruments MC-900 Multi-corer
PI Supplied Instrument Name: 10 L Niskin bottles attached to an Ocean Instruments MC-900 Multi-corer Instrument Name: Niskin bottle Instrument Short Name:Niskin bottle Instrument Description: A Niskin bottle (a next generation water sampler based on the Nansen bottle) is a cylindrical, non-metallic water collection device with stoppers at both ends. The bottles can be attached individually on a hydrowire or deployed in 12, 24, or 36 bottle Rosette systems mounted on a frame and combined with a CTD. Niskin bottles are used to collect discrete water samples for a range of measurements including pigments, nutrients, plankton, etc. Community Standard Description: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0412/
TriCarb 3110 TR liquid scintillation counter (Perkin Elmer)
TriCarb 3110 TR liquid scintillation counter (Perkin Elmer)
PI Supplied Instrument Name: TriCarb 3110 TR liquid scintillation counter (Perkin Elmer) Instrument Name: PerkinElmer Tri-Carb 3110TR low activity liquid scintillation analyzer Instrument Short Name:Tri-Carb 3110TR Instrument Description: The PerkinElmer Tri-Carb 3110TR is a benchtop liquid scintillation analyzer for detecting small amounts of alpha, beta, and gamma radioactivity. It features a Multichannel Analyzer with an effective resolution of 1/10 keV and an extended dynamic quench range. Sample capacity is either 408 standard 20 mL vials, or 720 small 4 or 7 mL vials. The instrument includes a barium-133 low-energy external standard source centered under the sample vial which eliminates the effects of volume variations. It has an energy range of 0-2000 keV and an operating ambient temperature range of 15-35 degrees Celsius.
Ultraviolet (UV) Light Box
Ultraviolet (UV) Light Box
PI Supplied Instrument Name: Ultraviolet (UV) Light Box Instrument Name: Ultraviolet Light Sterilization Device Instrument Short Name:UV Sterilizer Instrument Description: Ultraviolet (UV) light sterilization is a sterilization process that uses short wavelength radiation to kill microorganisms.
UV Steripen - Adventure Opti Model
UV Steripen - Adventure Opti Model
PI Supplied Instrument Name: UV Steripen - Adventure Opti Model Instrument Name: Ultraviolet Light Sterilization Device Instrument Short Name:UV Sterilizer Instrument Description: Ultraviolet (UV) light sterilization is a sterilization process that uses short wavelength radiation to kill microorganisms.
Cruise: PE17-20
PE17-20
R/V Pelican
Community Standard Description
International Council for the Exploration of the Sea
R/V Pelican
vessel
PE17-20
Jeffrey W. Krause
Dauphin Island Sea Lab
R/V Pelican
Community Standard Description
International Council for the Exploration of the Sea
R/V Pelican
vessel