This codebook.txt file was generated on <20170810> by ------------------- GENERAL INFORMATION ------------------- 1. Title of Dataset Iron sulfide formation on root surfaces of wild rice 2. Author Information Name: Sophia LaFond-Hudson Institution: University of MN Duluth Address:221 Swenson Civil Engineering 1405 University Drive Duluth, MN 55812 Email:lafo0062@d.umn.edu Name: Nathan Johnson Institution: University of MN Duluth Address:221 Swenson Civil Engineering 1405 University Drive Duluth, MN 55812 Email:nwjohnso@d.umn.edu Name:John Pastor Institution:University of MN Duluth Address:1035 Kirby Drive Swenson Duluth, MN 55812 Email:pastor@d.umn.edu Name:Brad Dewey Institution:University of MN Duluth Address:1035 Kirby Drive Swenson Duluth, MN 55812 Email:dewey@d.umn.edu 3. Date of data collection (single date, range, approximate date) 20150708-20150921 4. Geographic location of data collection (where was data collected?): University of MN Duluth Research Farm 5. Information about funding sources that supported the collection of the data: MN SeaGrant, Fond du Lac Band of Lake Superior Chippewa -------------------------- SHARING/ACCESS INFORMATION -------------------------- 1. Licenses/restrictions placed on the data: 2. Links to publications that cite or use the data: 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): 6. Recommended citation for the data: LaFond-Hudson, Sophia; Johnson, Nathan; Pastor, John; Dewey, Brad. (2017). Iron Sulfide Formation on the Root Surfaces of Wild Rice. Retrieved from the Data Repository for the University of Minnesota, https://doi.org/10.13020/D68W98. --------------------- DATA & FILE OVERVIEW --------------------- 1. File List A. Filename: FeS formation on root surfaces data Short description: Tab 1, Root surfaces: This file contains concentrations of root surface acid volative sulfide (AVS), solid phase iron (total Fe, Fe(II), Fe(III)), and chromium reducible sulfur (CRS). All units are umol/g dry mass. Tab 2, Sediment solid phase: This file contains concentrations of sediment AVS (umol/g) and solid phase iron (umol/g). Tab 3, Porewater: This file contains concentrations of porewater sulfide (umol/L), iron (umol/L), sulfate (umol/L), pH and saturation index. Tab 4, Plant: This file contains vegetative N (mg), total plant N (mg), seed count, weight (g) and N (mg). 2. Relationship between files: 3. Additional related data collected that was not included in the current data package: 4. Are there multiple versions of the dataset? no -------------------------- METHODOLOGICAL INFORMATION -------------------------- 1. Description of methods used for collection/generation of data: Full methods will be available in LaFond-Hudson et al, submitted 2017. Porewater was sampled using 5-cm length, 2-mm diameter tension lysimeter filters36 (Rhizons) attached with a hypodermic needle to an evacuated, oxygen-free serum bottle sealed with a 20 mm thick butyl-rubber stopper (Bellco Glass, Inc). The entire filter end of the Rhizon was inserted vertically into the sediment just below the surface. pH was measured at a depth of 5 cm. Roots were pulled from sediment and rinsed in deoxygenated water. Then roots were placed in jars of deoxygenated deionized water and placed in a nitrogen bag to be transported to a glove box. Sediment was sampled using a mini-core in bulk sediment away from the roots. The following variables were measured according to Greenberg, A. E., Clesceri, L. S. & Eaton, A. D. in Standard methods for the examination of water and wastewater , 1992)23 : Porewater sulfide was quantified with Hach Sulfide Reagents using the methylene blue method. Porewater and solid phase ferrous iron were quantified using the phenanthroline method. Total weak acid extractable iron was quantified through atomic absorbance spectrometry. Samples for porewater sulfate analysis were withdrawn from sulfide sampling bottles and filtered through a Dionex 1cc metal cartridge and a 0.45 μm polyethersulfone filter approximately three months after they were collected. Sulfate was quantified using a Dionex ICS-1100 Integrated IC system (AS-DV Autosampler). AVS was quantified using a diffusion method modified from Brouwer, H. & Murphy, T. Diffusion Method for the Determination of Acid-Volatile Sulfides (Avs) in Sediment. Environ. Toxicol. Chem. 13, 1273-1275 (1994). Chromium reducible sulfide was quantified using the method described in Burton, E. D., Sullivan, L. A., Bush, R. T., Johnston, S. G. & Keene, A. F. A simple and inexpensive chromium-reducible sulfur method for acid-sulfate soils. Appl. Geochem. 23, 2759-2766 (2008). Plant and seed N were dried for seven days at 65C, weighed, placed in polycarbonate vials with stainless steel balls, and shaken in a SPEX 800M mixer mill until samples were powdered. Samples were quantified for total N on a Finnigan Delta Plus XP isotope ratio monitoring mass spectrometer. 2. Methods for processing the data: Porewater sulfide: Absorbance at 662nm was divided by 0.02 to convert to umol/L Porewater iron: Absorbance at 510nm was divided by 0.005 to convert to umol/L AVS converted from mV to umol by using a calibration curve and volume of solution measured by electrode. Mass of AVS measured normalized by dry mass of root or sediment. Wet mass of roots or sediment used in extraction was multiplied by % solids to calculate dry mass. Iron converted from umol/L (FeII) or mg/L (total Fe) to umol/g dry mass by using volume of acid in extraction and % solids of root or sediment sample. 3. Instrument- or software-specific information needed to interpret the data: 4. Standards and calibration information, if appropriate: All instruments were calibrated with standards spanning their upper and lower detection limits. Calibration standards were not used in determining a calibration curve if they were more than 20% away from the expected concentration based on the calibration curve. 5. Environmental/experimental conditions: Sodium sulfate was added to surface water to reach concentrations of 300 mg/L sulfate. Controls had groundwater added, sulfate concentration ~8 mg/L. 6. Describe any quality-assurance procedures performed on the data: A materials recovery was done on each sample date to check the accuracy of the AVS extraction. Calibration standards were checked every 3-5 samples. Standard quality-assurance procedures (method blanks, duplicates, materials spikes, and calibration standard checks) were followed for quantification of total iron, sulfate, and plant/seed N. Deionized water blanks and method blanks were used during quantification of porewater iron, porewater sulfide, and solid-phase Fe(II) on the spectrophotometer. 7. People involved with sample collection, processing, analysis and/or submission: Investigators listed above. ----------------------------------------- DATA-SPECIFIC INFORMATION FOR: [Root surface] ----------------------------------------- 1. Number of variables: 7 2. Number of cases/rows: 64 3. Missing data codes: Code/symbol: n/a Definition: data not sampled or compromised during sampling 4. Variable List A. Name: Date Description: Julian date when samples were collected B. Name: Treatment Description: Surface water sulfate concentration +SO4 = 300 mg/L sulfate added sulfate control= no added sulfate C. Name: AVS Description: Concentration of acid volatile sulfide on root surface. Roots subsampled vertically for extraction of AVS. D. Name: Total Fe Description: Concentration of weak acid extractable iron, Fe(II) + Fe(III), on root surface E. Name: Fe(II) Description: Concentration of Fe(II) on root surface F. Name: Fe(III) Description: Concentration of Fe(III) on root surface. Calculated by subtracting Fe(II) from Total Fe. G. Name: CRS Description: Concentration of Chromium reducible sulfur on root surface. Roots subsampled vertically (separate subset of roots also analyzed for AVS). ----------------------------------------- DATA-SPECIFIC INFORMATION FOR: [Sediment solid phase] ----------------------------------------- 1. Number of variables: 4 2. Number of cases/rows: 11 3. Missing data codes: Code/symbol: n/a Definition: data not sampled or compromised during sampling 4. Variable List A. Name: Date Description: Julian date when samples were collected B. Name: Treatment Description: Surface water sulfate concentration +SO4 = 300 mg/L sulfate added sulfate control= no added sulfate C. Name: AVS Description: Concentration of acid volatile sulfide on sediment D. Name: Total Fe Description: Concentration of weak acid extractable iron, Fe(II) + Fe(III), on sediment ----------------------------------------- DATA-SPECIFIC INFORMATION FOR: [Porewater] ----------------------------------------- 1. Number of variables: 8 2. Number of cases/rows: 64 3. Missing data codes: Code/symbol: n/a Definition: data not sampled or compromised during sampling 4. Variable List A. Name: Date Description: Julian date when samples were collected B. Name: Treatment Description: Surface water sulfate concentration +SO4 = 300 mg/L sulfate added sulfate control= no added sulfate C. Name: Sulfide Description: Concentration of porewater sulfide D. Name: Sulfate Description: Concentration of porewater sulfate E. Name: Ferrous iron Description: Concentration of porewater Fe2+ F. Name: pH Description: pH measured with an electrode G. Name: IAP Description: Ion activity product. [HS-][Fe2+]/[H+] H. Name: Saturation index Description: Log10 of (IAP/Ksp). The log Ksp used was 2.95 from Stumm & Morgan. ----------------------------------------- DATA-SPECIFIC INFORMATION FOR: [Plant] ----------------------------------------- 1. Number of variables: 7 2. Number of cases/rows: 64 3. Missing data codes: Code/symbol: n/a Definition: data not available Code/symbol: 0 Definition: no seed present to measure 4. Variable List A. Name: Date Description: Julian date when samples were collected B. Name: Treatment Description: Surface water sulfate concentration +SO4 = 300 mg/L sulfate added sulfate control= no added sulfate C. Name: Vegetative N Description: Mass of nitrogen in stems and leaves, but not seeds. D. Name: Total plant N Description: Mass of nitrogen in stems, leaves, and seeds. E. Name: Seed count Description: Total number of seeds on individual plant F. Name: Seed weight Description: Mass of all seeds produced by plant. G. Name: Seed N Description: Total mass of N in all seeds produced by plant.