Concentrations of phospholipid-linked fatty acids (PLFAs) in the surface sediments of three marsh ponds in PIE-LTER (Rowley, MA) from 2014.

Website: https://www.bco-dmo.org/dataset/738160
Data Type: Other Field Results
Version: 1
Version Date: 2018-06-05

Project
» Eutrophication Effects on Sediment Metabolism and Benthic Algal-bacterial Coupling: An Application of Novel Techniques in a LTER Estuary (Benthic_PP_at_TIDE)
ContributorsAffiliationRole
Spivak, AmandaWoods Hole Oceanographic Institution (WHOI)Principal Investigator
Ake, HannahWoods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager

Abstract
Concentrations of phospholipid-linked fatty acids (PLFAs) in the surface sediments of three marsh ponds in PIE-LTER (Rowley, MA). Data were collected over 11 weeks in the summer and fall of 2014.


Coverage

Spatial Extent: Lat:42.738349 Lon:-70.809432
Temporal Extent: 2014 - 2014

Dataset Description

Concentrations of phospholipid-linked fatty acids (PLFAs) in the surface sediments of three marsh ponds in PIE-LTER (Rowley, MA). Data were collected over 11 weeks in the summer and fall of 2014.


Methods & Sampling

The three ponds are located in the high marsh (1.43-1.46 m above North American Vertical Datum of 1988) of the Plum Island Ecosystems – Long Term Ecological Research (PIE-LTER) site. Surface sediments were collected weekly for TOC, TN, δ13C, and δ15N (June 25-August 13 and November 11-25, 2014). Cores (5 cm diameter x 2 cm deep) were collected from three 1 m2 quadrats placed at random locations along two crisscrossing transects in each pond. Sediments were combined in combusted glass vials to form composite samples and stored (-80 ℃) until analysis. Lipid biomarker compounds were extracted using a modified Bligh & Dyer (1959) method (Spivak and Reeve 2015). Sediments were extracted with a methanol : chloroform : phosphate buffer saline mixture (2:1:0.8, v:v:v) using a microwave-accelerated reaction system (MARS6); samples were heated to 80°C for 10 min with continuous stirring. Samples were then partitioned and the organic phase removed. The total lipid extract was concentrated under N2 and samples were eluted on silica gel columns with chloroform, acetone (F1/2), and methanol (F3) (Guckert et al. 1985). The F3 (phospholipids) was dried under N2 and saponified with 0.5 M NaOH at 70°C for 4 h. Saponified samples were acidified and extracted 3 times with hexane. The extract was methylated with acidic methanol (95:5 methanol:HCl) and heated overnight at 70°C to form fatty acid methyl esters (FAME). Samples were analyzed with an Agilent 7890 gas chromatograph with the effluent split ~70:30 between a 5975C mass spectrometer and a flame ionization detector. Compounds were separated on an Agilent DB-5 ms column (60 m, 0.25 mm inner diameter, 0.25 μm film). FAME concentrations were quantified using methyl heneicosanoate as an internal standard. FAs are designated A:BωC, where A is the number of carbon atoms, B is the number of double bonds, and C is the position of the first double bond from the aliphatic ‘ω’ end of the molecule. Iso- and anteiso refer to whether the methyl group of branched compounds is attached to the penultimate or antepenultimate carbon atom.


Data Processing Description

BCO-DMO Data Processing Notes:

-reformatted column names to comply with BCO-DMO standards
-reformatted date to "yyyy-mm-dd"
-filled in blank cells with "nd"


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Data Files

File
PLFA.csv
(Comma Separated Values (.csv), 5.86 KB)
MD5:04c6a3c6f452e3d5ad303159b5823805
Primary data file for dataset ID 738160

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Related Publications

Spivak, A. C., Gosselin, K. M., & Sylva, S. P. (2018). Shallow ponds are biogeochemically distinct habitats in salt marsh ecosystems. Limnology and Oceanography. doi:10.1002/lno.10797
Results
Methods

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Parameters

ParameterDescriptionUnits
PondSite number unitless
WeekWeek number unitless
SeasonSeason at time of sampling unitless
TideTide type unitless
Sampling_DateSampling date; yyyy/mm/dd unitless
C12_0Concentration C12 0 per mil
iso_C13Concentration iso C13 per mil
anteiso_C13Concentration anteiso C13 per mil
C13_0Concentration C13 0 per mil
iso_C14Concentration iso C14 per mil
C14_0Concentration C14 0 per mil
iso_C15Concentration iso C15 per mil
anteiso_C15Concentration anteiso C15 per mil
C15_0Concentration C15 0 per mil
iso_C16Concentration iso C16 per mil
iso_16_1w9cConcentration iso 16 1w9c per mil
iso_16_1w9tConcentration iso 16 1w9t per mil
iso_16_1w7Concentration iso 16 1w7 per mil
C16_0Concentration C16 0 per mil
methyl_10_C16Concentration 10 methyl C16 per mil
iso_C17Concentration C17 per mil
anteiso_C17Concentration anteiso C17 per mil
C17_1Concentration C17 1 per mil
C17_0Concentration C17 0 per mil
C18_4Concentration C18 4 per mil
C18_2Concentration C18 2 per mil
C18_1Concentration C18 1 per mil
C18_0Concentration C18 0 per mil
iso_C19_0Concentration iso C19 0 per mil
C19_1Concentration C19 1 per mil
C20_4w6Concentration C20 4w6 per mil
C20_5w3Concentration C20 5w3 per mil
C20_3Concentration C20 3 per mil
C20_2Concentration C20 2 per mil
C20_1Concentration C20 1 per mil
C20_0Concentration C20 0 per mil
C22_6w6Concentration C22 6w6 per mil
C22_6w3Concentration C22 6w3 per mil
C22_5w6Concentration C22 5w6 per mil
C22_5w3Concentration C22 5w3 per mil
C22_1Concentration C22 1 per mil
C22_0Concentration C22 0 per mil
C24_0Concentration C24 0 per mil
C25_0Concentration C25 0 per mil
C26_0Concentration C26 0 per mil
C28_0Concentration C28 0 per mil
C30_0Concentration C30 0 per mil


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Instruments

Dataset-specific Instrument Name
Agilent 7890 gas chromatograph
Generic Instrument Name
Gas Chromatograph
Dataset-specific Description
Used to analyze samples
Generic 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)

Dataset-specific Instrument Name
Corer
Generic Instrument Name
Push Corer
Dataset-specific Description
Used for sediment samples
Generic Instrument Description
Capable of being performed in numerous environments, push coring is just as it sounds. Push coring is simply pushing the core barrel (often an aluminum or polycarbonate tube) into the sediment by hand. A push core is useful in that it causes very little disturbance to the more delicate upper layers of a sub-aqueous sediment. Description obtained from: http://web.whoi.edu/coastal-group/about/how-we-work/field-methods/coring/


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Deployments

Plum_Island

Website
Platform
shoreside Massachusetts
Start Date
2012-07-27
End Date
2012-08-15
Description
Plum Island, MA; LTER sites


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Project Information

Eutrophication Effects on Sediment Metabolism and Benthic Algal-bacterial Coupling: An Application of Novel Techniques in a LTER Estuary (Benthic_PP_at_TIDE)

Coverage: Plum Island Estuary, Rowley Massachusetts


Extracted from the NSF award abstract:
This project will address how rates of benthic microalgal production respond to eutrophication and geomorphological changes in human-impacted tidal creeks. Excess nutrient loading increases benthic algal biomass and likely stimulates production rates but the magnitude of nutrient and geomorphological effects on rates of production is unknown. Will changes in benthic algal productivity affect algal-bacterial coupling? Furthermore, how is algal-bacterial coupling affected by geomorphological changes, which may be exacerbated by excess nutrient loading but can also occur in pristine marshes?

This project will take advantage of the infrastructure of the TIDE project, a long-term saltmarsh eutrophication experiment at the Plum Island Ecosystem - Long Term Ecological Research site in Northeastern Massachusetts. Specifically, the PIs will measure benthic metabolism and examine algal- bacterial coupling in fertilized and ambient nutrient tidal creeks in the first field season. The following field season, they will compare sediment metabolism and carbon dynamics on slumped tidal creek walls (i.e. areas where low marsh has collapsed into the tidal creek) to that on the bottom of tidal creeks. In both years, gross and net production will be determined using an innovative triple oxygen isotope technique and traditional dissolved oxygen and inorganic carbon flux measurements. Comparisons between these methods will be useful in informing studies of sediment metabolism. Lipid biomarkers will be used to characterize the sources of organic matter to creek sediments, and stable isotope analysis of bacterial specific biomarkers to identify the sources of organic carbon utilized by sediment bacteria. The biomarkers will reveal whether sediment bacteria use organic matter substrates, such as benthic microalgal carbon, selectively or in proportion to availability. Overall, results from the proposed study will provide important information about how sediment carbon dynamics in shallow tidal creeks respond to long term eutrophication. Furthermore, findings will enhance understanding of the role of tidal creeks in coastal biogeochemistry.



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)

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