Katherine J. Knierim Erik D. Pollock Phillip D. Hays 20170401 Vector Digital Data Set (Point) https://doi.org/10.5066/F7610XJ5 Katherine J. Knierim Erik D. Pollock Matthew D. Covington Phillip D. Hays Kristofor R. Brye 201705 Publication (Journal) Geoderma Regional 10 Amsterdam, Netherlands Elsevier https://doi.org/10.1016/j.geodrs.2017.05.004 The nature of carbon (C) cycling in the vadose zone where groundwater is in contact with abundant gas-filled voids is poorly understood. The objective of this study was to trace C cycling in a karst landscape using stable-C isotopes, with emphasis on a shallow groundwater flow path through the soil, to an underlying cave, and to the spring outlet of a cave stream in the Ozark Plateaus of northwestern Arkansas. Blowing Spring Cave (BSC) occurs in the Springfield Plateau of the Ozark Plateaus. The cave passage is relatively horizontal, the entrance to BSC is a spring outlet, and no other human-sized entrances into the cave are known to occur. Soils generally are less than 2 to 3 meters thick above the cave and dominated by the Clarksville soil series (loamy-skeletal, siliceous, semiactive, mesic Typic Paleudults). Gas samples for carbon dioxide (CO₂) concentration and isotopic composition (δ¹³C-CO₂) and water samples for dissolved inorganic carbon (DIC) concentration and isotopic composition (δ¹³C-DIC) were collected from two suction-cup soil samplers above the cave (L1 and L2) and from within the cave. Cave-sampling locations included a drip-water pool fed by a waterfall in a side-passage of the cave (BS06), two locations along the main passage of the cave stream (BS07 and BS03), and at the spring outlet of the cave stream (BS01). Preliminary, intermittent sampling began in June 2011 and regular, bi-monthly sampling continued from March 2012 to May 2013, including storm-event sampling during high-flow conditions when discharge generally exceeded 0.5 cubic meters per second. This dataset includes inorganic carbon species concentrations and isotopic compositions (CO₂, δ¹³C-CO₂, DIC, δ¹³C-DIC, bicarbonate, carbonate, carbonic acid, and aqueous CO₂), physical water parameters (pH, specific conductance, temperature), calcium, calcite saturation, and stable C isotope equilibrium values (∆DIC-CO₂, εDIC-CO₂(g)) for samples collected at the BSC study site. For a complete description of sampling methods, laboratory analysis, and data analysis, see: Knierim, K.J., 2015. Stable Isotopes as a Tool to Characterize Carbon Cycling and Develop Hydrologic Budgets in Mantled Karst Settings (Dissertation). University of Arkansas, Fayetteville, Arkansas. This dataset was developed to complement interpretive work characterizing carbon cycling in the mantled karst setting of the Ozark Plateaus: Knierim, K.J., Pollock, E.D., Covington, M.D., Hays, P.D., and Brye, K.R., 2017, Carbon cycling in the mantled karst of the Ozark Plateaus, central United States: Geoderma Regional, v. 10, p. 64–76. 10.1016/j.geodrs.2017.05.004. This dataset is part of a larger dissertation work and details related to sample collection, laboratory analysis, data analysis, and statistical calculations can be found in: Knierim, K.J., 2015. Stable Isotopes as a Tool to Characterize Carbon Cycling and Develop Hydrologic Budgets in Mantled Karst Settings (Dissertation). University of Arkansas, Fayetteville, Arkansas. Chemical symbols in metadata are represented with Unicode UTF-8 superscripts and subscripts. For details see: http://www.unicode.org/charts/#symbols 20110622 20130506 ground condition Complete None planned -94.224548 -94.22037 36.450391 36.446014 ISO 19115 Topic Category environment None stable carbon isotopes cave karst USGS Metadata Identifier USGS:58af22ede4b01ccd54f9ef90 Common geographic areas Ozark Arkansas If using this dataset, reference the full citation including the digital object identifier (DOI) The data release has not been formally reviewed by the EPA, but has gone through the U.S. Geological Survey review and approval process. The views expressed in this data release are solely those of the authors and do not necessarily represent the views of the EPA. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. U.S. Geological Survey, Lower Mississippi-Gulf Water Science Center Katherine J Knierim Hydrologist mailing address

401 Hardin Rd

Little Rock AR 72211 United States 501-228-3600 kknierim@usgs.gov Funding for this research was provided by the Geological Society of America and the National Speleological Society. This manuscript was developed under STAR Fellowship Grant Number FP917347 awarded by the U.S. Environmental Protection Agency (EPA). The Arkansas Water Resources Center Water Quality Laboratory provided analytical support. Special thanks are given to the Bella Vista Property Owner’s Association for use of the research site and non-monetary support and to the Boston Mountain Grotto for mapping Blowing Springs Cave. Environment as of Metadata Creation: Microsoft [Unknown] Version 6.2 (Build 9200) ; Esri ArcGIS 10.4.1 (Build 5686) Service Pack N/A (Build N/A) The geochemical dataset was compiled from field parameters (pH and specific conductance) and laboratory results from the Arkansas Water Resources Center in Fayetteville, Arkansas (calcium), the University of Arkansas Stable Isotope Laboratory in Fayetteville, Arkansas (δ¹³C-CO₂), and the Colorado Plateau Stable Isotope Laboratory in Flagstaff, Arizona (DIC and δ¹³C-DIC). The dataset was checked for errors to ensure the merging process did not introduce typographical errors. Carbonate species (bicarbonate, carbonate, carbonic acid, and aqueous CO₂) and stable C isotope equilibrium values were calculated using equations described in Knierim (2015), following carbonate geochemistry equilibria methods from Dreybrodt (1988) and Stumm and Morgan (1996) and stable isotope equilibria equations from Clark and Fritz (1997). The dataset was checked for erroneous “null” (represented as -9999) or 0 values. The dataset represents samples collected for carbonate species and stable carbon isotope analyses, as part of a larger work in Knierim (2015) at Blowing Springs Cave in the Ozark Plateaus and published in Geoderma Regional. The dataset is considered complete for the scope of the information presented. Users are advised to read the rest of the metadata record carefully for additional details. Soil sampling locations were determined using topographic and aerial maps. Cave sampling locations were determined from a cave survey completed by the Boston Mountain Grotto, which used the entrance to BSC as the start of the survey. A formal accuracy assessment of the horizontal positional information in the dataset has not been conducted. Soil and cave sampling locations are represented as 2-dimensional points without explicit altitude data. A formal accuracy assessment of the vertical positional information in the dataset is not applicable. Clark, I.D. and Fritz, P. 1997 Publication (Book) New York, New York Lewis Publishers Digital and/or Hardcopy Resources 1996 publication date stable carbon isotope equilibria Stable carbon isotope enrichment factors used for calculating gross isotopic enrichment between aqueous dissolved inorganic carbon and gaseous carbon dioxide Dreybrodt, W. 1988 Publication (Book) New York, New York Springer-Verlag Digital and/or Hardcopy Resources 1988 publication date activity coefficients Chemical activity values used for calculating carbonate species in dissolved inorganic carbon Stumm, W. and Morgan, J.J. 1996 Publication (Book) New York, New York John Wiley and Sons, Inc. Digital and/or Hardcopy Resources 1997 publication date carbonate equilibria temperature-dependent carbonate equilibria values used for calculating carbonate species in dissolved inorganic carbon Water and gas samples for carbon species concentration and stable carbon isotopic compositions were collected from two soil suction-cup samplers (L1 and L2), a water-fall pool in a side passage of the cave (BS06), two locations along the cave stream (BS07, BS03), and at the spring outlet of the cave stream (BS01) from June 2011 to May 2013. Field parameters (including water temperature, pH, and specific conductance) were also recorded during sample collection. 20130506 Samples were kept on ice (4°C) until transported to environmental chambers at the Arkansas Water Resources Center Laboratory (AWRC) in Fayetteville, Arkansas, the Colorado Plateau Stable Isotope Laboratory (CPSIL) in Flagstaff, Arizona, or the University of Arkansas Stable Isotope Laboratory (UASIL) in Fayetteville, Arkansas for subsequent analysis. Calcium concentration was analyzed at AWRC via Inductively Coupled Plasma Optical Emission Spectrometry (Spectro Genesis). Dissolved inorganic carbon concentration and stable carbon isotope composition were analyzed at CPSIL on a Total Organic Carbon Analyzer (Aurora O.I.) interfaced to an Isotope Ratio Mass Spectrometer (IRMS) (ThermoQuest Delta plus XL) using a method modified where phosphoric acid converts dissolved inorganic carbon to gaseous carbon dioxide. Stable carbon isotope composition of gaseous carbon dioxide was analyzed at UASIL on a Gas Bench II interfaced to an IRMS (Thermo Finnigan Delta plus). 20131201 Carbonate species were calculated using carbonate equilibria values and equations from Stumm and Morgan (1996) and Dreybrodt (1988), which are fully described in Knierim (2015). Stable carbon isotope equilibria values were calculated using isotopic enrichment factors from Clark and Fritz (1997), which are fully described in Knierim (2015). 20150501 Geochemistry data were associated with sampling locations to create a Geographic Information System product. 20150101 Point Entity point 192 0.0197634048 0.0244529309 Decimal seconds D_NAD_1983_2011 GRS_1980 6378137.0 298.257222101 Attribute Table Table containing attribute information associated with the data set. Producer defined Date Date of sample collection, in the format M/D/YYYY Producer defined 6/22/2011 5/6/2013 Site Sampling site name Producer defined BS01 spring outlet (cave entrance) sampling location Producer defined BS03 cave stream sampling location Producer defined BS06 drip-water pool (fed by waterfall) in cave side passage sampling location Producer defined BS07 cave stream sampling location Producer defined L1 soil sampling location Producer defined L2 soil sampling location Producer defined GenSite General site description Producer defined cave cave sampling site Producer defined soil soil sampling site Producer defined Season Season of sampling collection Producer defined fall fall season samples, occurring between the September Equinox and the December Solstice Producer defined spring spring season samples, occurring between the March equinox and the June Solstice Producer defined summer summer season samples, occurring between the June Solstice and the September Equinox Producer defined winter winter season samples, occurring between the December Solstice and the March Equinox Producer defined Lat Latitude Producer defined 36.446014 36.450391 Decimal degrees Long Longitude Producer defined -94.224548 -94.22037 Decimal degrees Flow Designation of baseflow or storm-event sample, based on the slope of the receding limb of storm hydrographs Producer defined baseflow baseflow sample, generally less than 0.5 cubic meters per second Producer defined storm storm-event sample, generally greater than 0.5 cubic meters per second (but varies for individual storms) Producer defined Discharge Discharge measured at a compound 90 degree V-notch weir located approximately 50-m downstream of BS01 Producer defined 0.005 1.857 cubic meters per second pH Log of hydrogen ion concentration in water (nulls represented as -9999), measured in the field using a Thermo-handheld pH meter Producer defined -9999 8.8 standard units Temp_pH Water temperature from the Thermo-handheld pH meter (nulls represented as -9999) Producer defined -9999 26.3 Celsius SpecCond Specific conductance, or conductivity corrected for 25 degree celsius water (nulls represented as -9999), measured in the field using a VWR-handheld conductivity meter Producer defined -9999 288.1 microsiemens per centimeter Temp_sc Temperature from the VWR-handheld specific conductivity meter (nulls represented as -9999) Producer defined -9999 14.9 Celsius pH_est Estimated pH, using a linear interpolation from pH values collected before and after the sample time (nulls represented as -9999) Producer defined -9999 7.8 standard units Temp_est Estimated water temperature, using a linear interpolation from temperature values collected before and after the sample time (nulls represented as -9999) Producer defined -9999 14.9 Celsius Balance Absolute value of charge balance error between cations and anions (nulls represented as -9999) Producer defined -9999 33 percent Flag Flag for charge balance errors greater than plus or minus 5 percent Producer defined -9999 null Producer defined E Charge balance error greater than plus or minus 5 percent Producer defined Ca Calcium concentration (nulls represented as -9999) Producer defined -9999 83.2 mg/L CO2 Gaseous carbon dioxide concentration (nulls represented as -9999), measured in the field using a Vaisala CARBOCAP handheld carbon-dioxide meter Producer defined -9999 6070 ppmv CO2_iso Stable carbon isotope composition (ratio of ¹³C to ¹²C) of gaseous carbon dioxide (nulls represented as -9999), relative to Vienne Peedee Belemnite (VPDB) scale Producer defined -9999 -8.06 per mil DIC Aqueous dissolved inorganic carbon concentration (nulls represented as -9999) Producer defined -9999 36.1 mg/L DIC_iso Stable carbon isotope composition (ratio of ¹³C to ¹²C) of aqueous dissolved inorganic carbon (nulls represented as -9999), relative to Vienne Peedee Belemnite (VPDB) scale Producer defined -9999 -8.35 Bicarb Bicarbonate concentration, calculated from dissolved inorganic carbon concentration, water temperature, and pH (nulls represented as -9999) Producer defined -9999 0.00284 moles per liter Carb Carbonate concentration, calculated from dissolved inorganic carbon concentration, water temperature, and pH (nulls represented as -9999) Producer defined -9999 3.64E-05 moles per liter CarbAcid Carbonic acid concentration, calculated from dissolved inorganic carbon concentration, water temperature, and pH (nulls represented as -9999) Producer defined -9999 0.00028 moles per liter CO2_aq Dissolved (aqueous) carbon dioxide concentration, calculated from dissolved inorganic carbon concentration, water temperature, and pH (nulls represented as -9999) Producer defined -9999 0.000279 moles per liter Bicarb_per Percent of dissolved inorganic carbon composed of bicarbonate, based on pH and water temperature (nulls represented as -9999) Producer defined -9999 98 percent logSI Calcite saturation index, calculated from the log ratio of the ion activity product of calcium and carbonate to the temperature-dependent solubility product Producer defined -9999 0.73 DelDICCO2 Measured difference in stable carbon isotope composition between aqueous dissolved inorganic carbon and gaseous carbon dioxide (nulls represented as -9999) Producer defined -9999 12.9 per mil eDICCO2 Calculated gross equilibrium fractionation between aqueous dissolved inorganic carbon and gaseous carbon dioxide (nulls represented as -9999), based on the equilibrium fractionation between each carbonate species pair, water temperature, and pH Producer defined -9999 9 per mil Time Time of sample collection in 24-hour format of HH:MM in Central Standard Time (CST) Producer defined Unknown The entity and attribute information provided here describes the tabular data associated with the dataset. Please review the detailed descriptions that are provided (the individual attribute descriptions) for information on the values that appear as fields/table entries of the dataset. The entity and attribute information was generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information. U.S. Geological Survey ScienceBase mailing address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov The data release has not been formally reviewed by the EPA, but has gone through the U.S. Geological Survey review and approval process. The views expressed in this data release are solely those of the authors and do not necessarily represent the views of the EPA. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Vector Digital Data Set (Point) https://doi.org/10.5066/F7610XJ5 None. No fees are applicable for obtaining the dataset. 20200821 Katherine J Knierim U.S. Geological Survey, Lower Mississippi-Gulf Water Science Center Hydrologist mailing address

401 Hardin Rd

Little Rock AR 72211 United States 501-228-3600 kknierim@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998