DOI: 10.5061/dryad.sbcc2frjg
title: Stable isotope values from coastal Louisiana mangrove and salt marsh communities in May 2016

description: The salt marshes along the Gulf of Mexico provide a critical habitat for
 many species, but their spatial distribution is changing, because black
 mangroves (Avicennia germinans) are expanding due to warmer winters.
  This dataset provides bulk carbon, nitrogen and sulfur stable
 isotope values of primary producers, soil organic matter, and common
 aquatic consumers collected in Spartina alterniflora-dominated (salt
 marsh), Avicennia dominated (mangrove), and mixed (transitional) habitats
 at two locations in coastal Louisiana. These data can be used to assess
 the relative importance of specific basal carbon sources to soil organic
 matter and aquatic consumers across habitat types.
description: These data were collected in May 2016 in southeastern Louisiana
 along the northern coast of the Gulf of Mexico.  Samples were collected at
 two locations: Grand Isle (29.223626°, -90.043768°) and Bay Champagne
 (29.138952°, -90.178298°). Three habitat types were sampled at each
 location: a salt marsh area dominated by <em>Spartina
 alterniflora</em>, a mangrove area dominated by <em>Avicennia
 germinans</em> and a mixed area with vegetation transitional between
 these two habitat types. At each site and habitat type suspended
 particulate organic matter, was collected from overlying water on the
 habitat edge and filtered on a combusted GF/C filter.  A 3 cm diameter x 5
 cm length core was collected for soil organic matter, surface sediment was
 extracted for benthic microalgae collection, and aquatic consumers were
 collected using fyke nets, wire minnow traps, suction sampling, and other
 quadrat-based and opportunistic methods. Samples were measured, dried,
 homogenized and then analyzed for carbon, nitrogen, and sulfur elemental
 concentrations and stable isotope values using an elemental analyzer
 system coupled to a continuous-flow stable isotope ratio mass
 spectrometer.
description: # Stable isotope values from coastal Louisiana mangrove and salt marsh
 communities in May 2016 Dataset DOI:
 [10.5061/dryad.sbcc2frjg](10.5061/dryad.sbcc2frjg) ## Description of the
 data and file structure These data were collected in May 2016 in
 southeastern Louisiana along the northern coast of the Gulf of Mexico at
 two locations: Grand Isle (29.223626°, -90.043768°) and Bay Champagne
 (29.138952°, -90.178298°). Three habitat types were sampled at each
 location: a salt marsh, mangrove, and a mixed habitat transitional between
 these two vegetation types. At each site and habitat representative
 samples of primary producers, soil organic matter, and aquatic consumers
 were collected and analyzed for carbon, nitrogen, and sulfur elemental
 concentrations and stable isotope values using an elemental analyzer
 system coupled to a continuous-flow stable isotope ratio mass
 spectrometer. Sample precision based on repeated reference materials were
 0.05 ‰ for δ13C, 0.15‰ for δ15N and 0.30‰ for δ43S, respectively. ###
 Files and variables #### File:
 Powell\_et\_al.\_LASG\_Stable\_Isotope\_Data.xlsx
 **Description:** Definitions of dataset terms are found in the table below
 using the "Variables: Description / Units" format.
 "NA" in a cell indicates not applicable or not available data.
 Contact [polito@ucsc.edu](mailto:polito@ucsc.edu) if questions. #####
 Variables: No: Running sample number | None Sample_ID: Individual sample
 code | None Location: Name of location where sample was collected | None
 Habitat: Type of habitat where sample was collected | None Site_Code: Code
 that references both site and habitat where sample was collected | None
 Method: Type of sampling method used to collect sample | None
 Method_Replicate: Unique deployment ID for each replicate collection
 method | None Date: The date of sample collection in MM/DD/YYYY format |
 None Latitude: Sample collection latitude | Decimal degrees Longitude:
 Sample collection longitude | Decimal degrees Group: The broad taxonomic
 group | None Taxa: The specific scientific or taxonomic name | None
 Common_name: The common taxonomic name | None n: The number of individuals
 used to create the sample | None Size_mm: The individual (n=1) or mean
 (n&gt;1) size of aquatic consumers | mm Size_Method: The size method used
 (TL = total length, CW = carapace width, SH = shell height) | None Tissue:
 The tissue type analyzed | None Sample_Prep: A notation that sample were
 not lipid extracted prior to analysis | None S%: Sulfur (S) elemental
 concentration in sample as percentage of dry weight | % d34S: Sulfur (S)
 isotopic value in sample expressed in the delta (δ) notation | ‰ C%:
 Carbon (C) elemental concentration in sample as percentage of dry weight
 |% d13C: Carbon (C) isotopic value in sample expressed in the delta (δ)
 notation | ‰ N%: Nitrogen (N) elemental concentration in sample as
 percentage of dry weight | % d15N:  Nitrogen (N) isotopic value in sample
 expressed in the delta (δ) notation | ‰ CN_ratio: Carbon (C) to nitrogen
 (N) elemental ratio in sample | None ## Code/software Not applicable ##
 Access information Data was derived from the following sources: * Powell,
 Christina, "Influence of Black Mangrove Expansion on Salt Marsh
 Faunal Communities of Eastern Coastal Louisiana" (2018). *LSU
 Master's Theses*. 4633.\
 [https://repository.lsu.edu/gradschool_theses/4633](https://repository.lsu.edu/gradschool_theses/4633)