------------------- GENERAL INFORMATION ------------------- 1. Title of Dataset: Data and R code for a zooplankton ethanol storage isotope correction factor. 2. Author Information Principal Investigator Contact Information Name: Tristan Blechinger Institution: University of Minnesota Address: 135 Skok Hall, 2003 Upper Buford Circle, St. Paul, MN 55108 Email: blech024@umn.edu ORCID: https://orcid.org/0009-0005-6730-8856 Associate or Co-investigator Contact Information Name: Denver Link Institution: University of Minnesota Address: 135 Skok Hall, 2003 Upper Buford Circle, St. Paul, MN 55108 Email: linkx168@umn.edu ORCID: https://orcid.org/0000-0001-5596-6417 Associate or Co-investigator Contact Information Name: Gretchen Hansen Institution: University of Minnesota Address: 135 Skok Hall, 2003 Upper Buford Circle, St. Paul, MN 55108 Email: ghansen@umn.edu ORCID: https://orcid.org/0000-0003-0241-7048 3. Date of data collection: 2022_06_07 through 2022_06_24 5. Geographic location of data collection: Lakes in Minnesota, indexed by DOW number: Lake Name (DOW) Big Sandy (1006200) Buffalo (86009000) Shamineau (49012700) Alexander (49007900) Chippewa (21014500) 6. Information about funding sources that supported the collection of the data: United States Geological Survey in cooperation with the National Institutes for Water Resources (Project ID 2020MN105AIS) 7. Overview of the data (abstract): This data set contains fresh and ethanol storage zooplankton samples collected from five Minnesota lakes during June 2022. The data were collected with five paired sites at each lake. The samples were filtered to remove detritus, phytoplankton, and predatory invertebrates. After filtering, each sample was split between fresh processing and ethanol storage. Ethanol storage samples remained in storage for approximately one month. Samples were sent to the UC-Davis Stable Isotope Facility for analysis. Stable isotope values in addition to lake name, DOW, and site of collection are included in the data file. Bayesian Hierarchical models were used to establish correction factors for ethanol storage. Statistical analysis was performed using the R package brms and model output can be found in respective .rds files. Details for each file can be found in the readme file. -------------------------- SHARING/ACCESS INFORMATION -------------------------- 1. Links to publications that cite or use the data: Blechinger, T., Link, D., Nelson, JKR., Hansen, GJA. Estimating ethanol correction factors for δ13C and δ15N isotopic signatures of freshwater zooplankton from multiple lakes. In preparation. 2. Terms of Use: Data Repository for the U of Minnesota (DRUM) By using these files, users agree to the Terms of Use. https://conservancy.umn.edu/pages/drum/policies/#terms-of-use --------------------- DATA & FILE OVERVIEW --------------------- 1. File List 1. Filename: isotopedata.csv Short description: Stable isotope data for fresh and treated zooplankton samples sorted by lake and site. 2. Filename: correction.model.rmd Short description: Bayesian hierarchical models used to determine correction factors for carbon-13 and nitrogen-15. Code also contains k-fold cross validation tests and plots of results. 3. Filename: carbon_model_centered.rds Short description: Model output for carbon-13. 4. Filename: nitrogen_model_centered.rds Short description: Model output for nitrogen-15. 5. Filename: kfoldcarboncentered.rds Short description: K-fold cross validation test output for carbon-13. 6. Filename: kfoldnitrogencentered.rds Short description: K-fold cross validation test output for carbon-13. 2. Relationship between files: Correction model code reads in isotope data file and models/tests produce the various rds files as outputs. -------------------------- METHODOLOGICAL INFORMATION -------------------------- 1. Description of methods used for collection/generation of data: Zooplankton were collected at five sites at five lakes throughout June of 2022. Sites were geographically dispersed at depths >10m. Samples were collected via vertical tow of an 80μm mesh net. After completing the vertical tow, samples were placed in a 250ml Nalgene bottle in a cooler to ensure gut clearance. Samples were filtered through 850μm, 250μm, and 120μm four-inch zooplankton sieves once gut clearance was completed, removing the majority of debris and excess algae. Half of the sample from each site was processed for isotope analysis as fresh while the remaining half was placed in 90.25% reagent grade ethanol. All zooplankton samples were dried at 60℃, ground to a powder, and encapsulated at weights of 1mg (+/-0.2) for dual δ13C and δ15N stable isotope analysis at the UC-Davis Stable Isotope Facility. 2. Methods for processing the data: Programs were written for Program R and all code required to replicate analysis is included. Analyses were performed using R version 4.2.2. 3. Instrument- or software-specific information needed to interpret the data: Program R is required to run the analysis. 4. Standards and calibration information, if appropriate: Delta values for stable isotopes are expressed relative to international standards VPDB (Vienna Pee Dee Belemnite) and atmospheric N2 (air) for carbon and nitrogen, respectively. Calibration data for stable isotope analysis: During analysis, samples are interspersed with several replicates of at least four different laboratory reference materials. These reference materials have been previously calibrated against international reference materials, including: IAEA-600, USGS-40, USGS-41, USGS-42, USGS-43, USGS-61, USGS-64, and USGS-65) reference materials. A sample’s provisional isotope ratio is measured relative to a reference gas peak analyzed with each sample. These provisional values are finalized by correcting the values for the entire batch based on the known values of the included laboratory reference materials. The long term standard deviation is 0.2 ‰ for 13C and 0.3 ‰ for 15N. (https://stableisotopefacility.ucdavis.edu/carbon-and-nitrogen-solids) 5. People involved with sample collection, processing, analysis and/or submission: Tristan Blechinger, Denver Link, Jenna Ruzich, Nikayla Barnes, Gretchen Hansen. ----------------------------------------- DATA-SPECIFIC INFORMATION FOR: isotopedata.csv ----------------------------------------- 1. Number of variables: 7 2. Number of cases/rows: 23 3. Variable List 1. Name: Lake Description: Name of lake where sample was collected. 2. Name: DOW Description: State of Minnesota unique lake identifier. 3. Name: Site Description: Site ID of paired sample. 4. Name: Fd.13.C Description: Quantity of carbon-13 for fresh (untreated) samples. 5. Name: Ed.13.C Description: Quantity of carbon-13 for ethanol treated samples. 6. Name: Fd.15.N Description: Quantity of nitrogen-15 for fresh (untreated) samples. 7. Name: Ed.15.N Description: Quantity of nitrogen-15 for ethanol treated samples.