Dataset: EN638 Bacterial Productivity
Deployment: EN638

Principal Investigator:

Carol Arnosti (University of North Carolina at Chapel Hill, UNC-Chapel Hill)

Contact:

Carol Arnosti (University of North Carolina at Chapel Hill, UNC-Chapel Hill)

BCO-DMO Data Manager:

Karen Soenen (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

A mechanistic microbial underpinning for the size-reactivity continuum of dissolved organic carbon degradation (Microbial DOC Degradation)

Data URL:

https://www.bco-dmo.org/dataset-deployment/820682/data

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Description

Bacterial production was estimated from 3H-leucine incorporation by heterotrophic bacteria using a cold trichloroacetic acid (TCA) and microcentrifuge extraction method (Kirchman, 2001). All work and incubations were performed in a UNOLS isotope lab.

Methods & Sampling

Dataset acquisition description

Samples were collected in one of two ways:

Bulk water from each station was collected by combining equal portions from three niskin bottles triggered at each depth into an acid washed glass media bottle.
After shaking, large volume (mesocosm) incubations were sampled by pouring into 500 mL acid washed glass media bottles.

Data Processing Description

Dataset Processing Description

To 1.5ml triplicate subsamples and one 100% (w/v) TCA -killed control 23 uL of L-[3,4,5-3H(N)]-Leucine (PerkinElmer, NET460250UC) was added and incubated between 10 and 40 hours at near in situ temperature. Live samples were then killed with 89 uL of 100% (w/v) TCA and centrifuged (10,000 rpm at 4°C for 10 min) to pelletize cell material. The supernatant liquid was removed and 1 mL of 5% (w/v) TCA solution was added followed by vortex mixing and centrifugation. Supernatant removal, mixing, and centrifugation were repeated using 1 mL of 80% ethanol solution. Again, the supernatant liquid was removed and each sample was left to dry in a hood overnight. After drying, 1 mL of scintillation cocktail (ScintiSafe 30% Cocktail, Fisher SX23-5) was added and incorporated radioactivity was measured using a PerkinElmer Tri-Carb 2910TR LSA scintillation counter for bulk, and PerkinElmer Tri-Carb 3110TR LSA for large volume (mesocosm) samples. Radioactivity was compared to 1 mL of scintillation cocktail spiked with 23 uL of L-[3,4,5-3H(N)]-Leucine radioactivity and divided by incubation time to calculate.

Data processing was done using excel.

BCO-DMO processing notes:

Adjusted column names to comply with database requirements
Added ISO_DateTine_UTC column
Converted data to ISO format (yyyy-mm-dd)

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-1736772	NSF Division of Ocean Sciences

Instruments

Liquid Scintillation Counter

Supplied Name: PerkinElmer Tri-Carb 2910TR LSA, PerkinElmer Tri-Carb 3110TR LSA

Supplied Description:

Instrument Type

Generic Name: Liquid Scintillation Counter

Acronym: LSC

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB21/

Generic Description:

Liquid scintillation counting is an analytical technique which is defined by the incorporation of the radiolabeled analyte into uniform distribution with a liquid chemical medium capable of converting the kinetic energy of nuclear emissions into light energy. Although the liquid scintillation counter is a sophisticated laboratory counting system used the quantify the activity of particulate emitting (ß and a) radioactive samples, it can also detect the auger electrons emitted from 51Cr and 125I samples.

Liquid scintillation counters are instruments assaying alpha and beta radiation by quantitative detection of visible light produced by the passage of rays or particles through a suitable scintillant incorporated into the sample.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
deployment	Cruise ID	unitless	cruise_id
station	Station number for cruise	unitless	station
latitude	Latitude, west is negative	decimal degrees	lat
longitude	Longitude, south is negative	decimal degrees	lon
date	Date of sample collection in ISO format (yyyy-mm-dd), US Eastern Time (UTC-05:00)	unitless	date
time	Time of sample collection in ISO format (hh:mm:ss), US Eastern Time (UTC-05:00)	unitless	time
cast_number	Cast number (refers to cast of CTD/Niskin bottles on cruise)	unitless	cast
depth_sequence	Sequence of depths sampled (1 is surface; higher numbers at greater depths)	unitless	depth
depth_actual	Actual depth at which water was collected	meters (m)	depth
sample_type	Sample from bulk water or Large Volume incubation	unitless	sample_descrip
unammended_ammended	Whether high molecular weight thalassiosira weissflogii extract was added or not; A, B, C refers to incubation depth, and the following number corresponds to incubation replicate.	unitless	sample_descrip
substrate	[3H] Leucine substrate added for measurement of bacterial productivity	unitless	sample_descrip
timepoint	sampling point (0, 1, 2, …) post-incubation	unitless	time_sample
time_elapsed	Incubation time	hours (hrs)	time_inc
incorporation_rate	Average 3H-Leu (pM) incorporation/hr	pmol L-1 h-1	leuc_incorp
incorporation_rate_std_dev	Deviation of incorporation rates	pmol L-1 h-1	leuc_sd
ISO_DateTime_UTC	Datetime of sample collection in ISO format in UTC timezone (yyyy-mm-dd:hh:mm:ssZ)	yyyy-MM-dd'T'HH:mm:ss'Z'	ISO_DateTime_UTC

Database

Contribute Data

Dataset: EN638 Bacterial Productivity
Deployment: EN638

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: EN638 Bacterial ProductivityDeployment: EN638

Dataset acquisition description

Dataset Processing Description

Dataset: EN638 Bacterial Productivity
Deployment: EN638