This readme.txt file was generated on <2020-08-30> by ------------------- GENERAL INFORMATION ------------------- 1. Title of Dataset Content of leaf pigments of tree and grassland species collected at the Cedar Creek Ecosystem Science Reserve in 2015 and 2016 2. Author Information Principal Investigator Contact Information Name: Jeannine Cavender-Bares Institution: University of Minnesota Address: 1475 Gortner Ave, Saint Paul, MN 55108 Email: cavender@umn.edu ORCID: 0000-0003-3375-9630 Associate or Co-investigator Contact Information Name: Anna K Schweiger Institution: University of Minnesota Address: Email: anna.k.schweiger@gmail.com ORCID: 0000-0002-5567-4200 Associate or Co-investigator Contact Information Name: Brett Fredericksen Institution: University of Minnesota Address: Email: ORCID: Associate or Co-investigator Contact Information Name: Cathleen Lapadat Institution: University of Minnesota Address: 1475 Gortner Ave, Saint Paul, MN 55108 Email: nguye618@umn.edu ORCID: 3. Date of data collection: 2015-08-10 to 2016-08-10 4. Geographic location of data collection (where was data collected?): Cedar Creek Ecosystem Science Reserve in East Bethel, MN 5. Information about funding sources that supported the collection of the data: Sponsorship: DEB-1342872; DEB-1342778; DEB-1342827; DEB-1342823; DEB-1234162; iCORE/AITF (G224150012 and 200700172); NSERC (RGPIN-2015-05129); CFI (26793) -------------------------- SHARING/ACCESS INFORMATION -------------------------- 1. Licenses/restrictions placed on the data: Creative Commons Attribution-NonCommercial-NoDerivs 3.0 United States, http://creativecommons.org/licenses/by-nc-nd/3.0/us/ 2. Links to publications that cite or use the data: https://doi.org/10.1038/s41559-018-0551-1 https://doi.org/10.1016/j.rse.2018.11.016 https://doi.org/10.1101/2020.04.24.060483 3. Links to other publicly accessible locations of the data: 4. Links/relationships to ancillary data sets: 5. Was data derived from another source? If yes, list source(s):No 6. Recommended citation for the data: Schweiger, Anna K; Fredericksen, Brett; Lapadat, Cathleen; Cavender-Bares, Jeannine. (2020). Content of leaf pigments of tree and grassland species collected at the Cedar Creek Ecosystem Science Reserve in 2015 and 2016. Retrieved from the Data Repository for the University of Minnesota, https://doi.org/10.13020/j7fw-2g91. -------------------------- METHODOLOGICAL INFORMATION -------------------------- 1. Description of methods used for collection/generation of data: Fresh leaf-tissue samples were collected in the field, cut with a hole punch and stored in liquid nitrogen. 2. Methods for processing the data: The content of chlorophyll a, chlorophyll b, β-carotene, lutein, neoxanthin, violaxanthin, antheraxanthin and zeaxanthin pigments was determined using high-performance liquid chromatography (HPLC). For extraction, leaf samples were ground in 80% acetone and centrifuged for 2 min at 13,000 r.p.m. The supernatant was collected with a syringe and the pellet re-extracted in 100% acetone and centrifuged again for 2 min at 13,000 r.p.m. The pooled supernatant was then filtered through a 0.45 μm nylon filter (Millex-HV, Millipore). Our HPLC system (Agilent 1200 Series, Agilent Technologies) included a diode array detector, quaternary pump and 250 mm × 4.6 mm octadecyl-silica column with 5 μm particle size (Allsphere ODS-1 Column, Grace). Solvent programs were adapted from Gilmore & Yamamoto (1991). We injected 20 μl pigment extract per sample and set the flow rate to 2 ml min–1. Solvent A consisted of a mix of acetonitrile:methanol:0.1 M Tris pH 8.0 buffer (8:1:1). Solvent B consisted of a mix of methanol:ethyl acetate (68:32). Solvent A was run for 12 min followed by a 4 min gradient from solvent A to solvent B. Solvent B was run for 2 min followed by a 1 min gradient from solvent B to solvent A to reach column equilibrium. Peaks were detected at 445 nm and peak-area units were measured using the ChemStation Software (Agilent Technologies). We calculated pigment concentrations from HPLC peak areas using calibration equations developed from HPLC peak-area units of pure pigments in dilution series, involving 8 steps for β-carotene, 14 steps for chlorophyll a and 16 steps for all other pigments, covering the entire expected range of pigment concentrations in our samples. Chlorophyll a, chlorophyll b and β-carotene were extracted from spinach with thin-layer chromatography (Quach et al. 2004) and re-dissolved in 100% acetone. Purified lutein was obtained from Sigma–Aldrich. The concentration of the pigment standards in dilution series were determined based on their absorbance measured with a UV-Vis spectrophotometer (Cary 50 Bio, Agilent Technologies) at 445 nm and corresponding extinction coefficients (see Watanabe et al. 1984; Zieger & Egle 1965; Hiyama et al. 1969; Aasen & Jensen 1966). Calibration equations for neoxanthin, violaxanthin, antheraxanthin and zeaxanthin were based on normalized coefficients and lutein area units (De las Rivas et al. 1989). Pigment concentrations (ng.mg–1) were transformed to moles per unit area based on the size of the hole punch. References Gilmore, A. M. & Yamamoto, H. Y. Resolution of lutein and zeaxanthin using a non-endcapped, lightly carbon-loaded C18 high-performance liquid chromatographic column. J. Chromatogr. A 543, 137–145 (1991) Quach, H. T., Steeper, R. L. & Griffin, G. W. An improved method for the extraction and thin-layer chromatography of chlorophyll a and b from spinach. J. Chem. Educ. 81, 385 (2004) Watanabe, T. et al. Preparation of chlorophylls and pheophytins by isocratic liquid chromatography. Anal. Chem. 56, 251–256 (1984) Zieger, R., & Egle, K. Zur quantitativen Analyse der Chloroplasten Pigmente. I. Kritische Überprüfung der spektralphotometrischen Chlorophyllbestimmung. Beitr. Biol. Pflanz 41, 11–37 (1965) Hiyama, T., Nishimura, M. & Chance, B. Determination of carotenes by thin-layer chromatography. Anal. Biochem. 29, 339–342 (1969) Aasen, A. & Jensen, S. L. Carotenoids of flexibacteria. IV. The carotenoids of two further pigment types. Acta Chem. Scand. 20, 2322–2324 (1966) De las Rivas, J., Abadía, A. & Abadía, J. A new reversed phase-HPLC method resolving all major higher plant photosynthetic pigments. Plant Physiol. 91, 190–192 (1989) 3. Instrument- or software-specific: Agilent 1200 Series, Cary 50 Bio, Chemstat Software: Agilent Technologies, Santa Clara, CA, USA Allsphere ODS-1 Column, Grace, Columbia, MD, USA 4. Standards and calibration information, if appropriate: Purfied lutein from Sigma–Aldrich, St. Luis, MO, USA 5. Environmental/experimental conditions: Dry field conditions 6. Describe any quality-assurance procedures performed on the data: Two blank run per cycle, duplicates run for all samples 7. People involved with sample collection, processing, analysis and/or submission: Anna K. Schweiger (collection, processing, analysis, submission) Brett Fredericksen (collection, processing) Cathleen Lapadat (processing) Jeannine Cavender-Bares (submission) Ian Carrier (collection) Lewis French (collection) Erin Murdock (collection) Craig See (collection) Travis Cobb (collection) Shan Kothari (collection) --------------------- DATA & FILE OVERVIEW --------------------- This data set contains the content of chlorophyll a, chlorophyll b, β-carotene, lutein, neoxanthin, violaxanthin, antheraxanthin and zeaxanthin pigments from tree and grassland species sampled at the Cedar Creek Ecosystem Science Reserve in East Bethel, MN. Mass- and area-based pigment contents were determined using high-performance liquid chromatography (HPLC). Data were collected as part of the Dimensions of Biodiversity project “Linking remotely sensed optical diversity to genetic, phylogenetic and functional diversity to predict ecosystem processes”. Samples were collected in or near the old fields chronosequence, the oak savanna, and the Forest and Biodiversity Experiment (FAB 1) plots. We used this data together with leaf-level spectral measurements to build partial least squares regression (PLSR) models for predicting leaf traits from spectra. 1. File List A. Filename: DOB_pigments.csv Short Description: Leaf pigment content data Size: Type: CSV file ----------------------------------------- DATA-SPECIFIC INFORMATION FOR: DOB_pigments.csv ----------------------------------------- 1. Number of variables: 19 2. Number of cases/rows: 125 3. Missing data codes: NA 4. Variable List A. nam: sample name, including location code B. abbrev: species abbreviation C. species: species name D. NEO_ng_mg: neoxanthin (ng.mg-1) E. VIO_ng_mg: violaxanthin (ng.mg-1) F. ANT_ng_mg: antheraxanthin ((ng.mg-1) G. LUT_ng_mg: lutein (ng.mg-1) H. ZEA_ng_mg: zeaxanthin (ng.mg-1) I. CHLB_ng_mg: chlorophyll b (ng.mg-1) J. CHLA_ng_mg: chlorophyll a (ng.mg-1) K. CAR_ng_mg: beta-carotene (ng.mg-1) L. NEO_umol_m2: neoxanthin (μmol.m-1) M. VIO_umol_m2: violaxanthin (μmol.m-1) N. ANT_umol_m2: antheraxanthin (μmol.m-1) O. LUT_umol_m2: lutein (μmol.m-1) P. ZEA_umol_m2: zeaxanthin (μmol.m-1) Q. CHLB_umol_m2: chlorophyll b (μmol.m-1) R. CHLA_umol_m2: chlorophyll a (μmol.m-1) S. CAR_umol_m2: beta-carotene (μmol.m-1)