Title:
Author:
Affiliation: Brigham Young University, Department of Biology
Address: 401 WIDB, Brigham Young University, Provo, Utah 84602
Phone: 801-422-2175
Email:
Sponsors:
Date Created:
Date Last Modified:
Abstract:
Methods:
Purpose:
Column Values and Details:
SampleID – A number assigned to each sample when they are brought into the lab, recorded, extracted, and entered into the computer.
Elevation – Values are “upper” or “lower” and designates which of the study sites the samples were taken from. Upper elevation sites are approximately 9500 feet and lower elevation sites are approximately 8700 feet.
Cover – “meadow” or “aspen”
SiteNumber – Values 1 through 12. Each site is number so that it is easy to keep track of where the data are coming from. Sites 1, 3, and 5 are in the lower meadow; sites 2, 4, and 6 are in the lower aspen; sites 7, 9, and 11 are in the upper meadow; and sites 8, 10, and 12 are in the upper aspen.
Treatment – “Dust,” “Control,”, or “Dust Control” refers to the dust treatment.
CollectionDate – The date soil cores were collected from the field.
ExtractionDate – The date soils were extracted in the lab.
InitialORIncubated – “Initial” refers to the core that was brought back to the lab. “Incubated” refers to the core that was left in the field for 28 days.
GramsOfSoilExtracted – Mass in grams of soil and water that was extracted.
TinNumber – Is the number that is written on the soil tin used to weigh and dry the soil
TinMass - Mass of the empty tin (grams)
WetSoilPlusTin – Mass of the wet soil plus the tin (grams)
DrySoilPlusTin – Mass of the dry soil and the tin after 48 hours in the drying oven on low temperature (grams)
DrySoilMass – Is = DrySoilPlusTin – TinMass (grams)
WetSoilMass – Is = WetSoilPlusTin – TinMass (grams)
WaterMass – Is = WetSoilMass – DrySoilMass (grams)
ProportionDrySoil – Is = DrySoilMass / WetSoilMass (proportion grams/gram)
MassOfSoil – Is = PercentDrySoil * GramsOfSoilExtracted (grams)
GravimetetricWaterContent – is = WaterMass / WetSoilMass (grams/gram)
NH4Absorbance1 – is the absorbance value at 650 nm using the NH4 protocol for the first replicate of the sample
NH4Absorbance2 - is the absorbance value at 650 nm using the NH4 protocol for the second replicate of the sample
NH4StandardRegressionSlope – is the slope of the regression line calculated from the standards in the NH4 protocol
NH4StandardRegressionIntercept – is the intercept of the regression line calculated from the standards in the NH4 protocol
NH4ppmSample1 – NH4 concentration in ppm calculated from the standard regression line for the first replicate of the sample. Is = (NH4Absorbance1 * NH4StandardRegressionSlope) + NH4StandardRegressionIntercept
NH4ppmSample2 - NH4 concentration in ppm calculated from the standard regression line for the second replicate of the sample. Is = (NH4Absorbance2 * NH4StandardRegressionSlope) + NH4StandardRegressionIntercept
NH4ppmSampleAverage – Is = Average(NH4ppmSample1, NH4ppmSample2)
NH4DilutionFactor1 – the dilution factor of the soil extraction procedure. Is = (MassOfSoil + 30 mL of extractant)/MassOfSoil. The number is unitless and should be between 2 and 3.
NH4DilutionFactor2 – the dilution factor for combining the sample with the reagents. The number is unitless and should be 1.5 for the NH4 protocol.
NH4DilutionFactor3 – the dilution factor for samples that were diluted because of NH4 concentrations above 3 ppm. If samples were not diluted in this step the number is 1. If they were diluted to half of the previous concentration then the number is 2. If they were diluted to one-third of the previous concentration the number is 3.
NH4ConcentrationSoilPpm – This is the concentration of NH4 in the soil in ppm. Is = NH4ppmSampleAverage * NH4DilutionFactor1 * NH4DilutionFactor2 * NH4DilutionFactor3.
NO3Absorbance1 – is the absorbance value at 540 nm using the NO3 protocol for the first replicate of the sample
NO3Absorbance2 – is the absorbance value at 540 nm using the NO3 protocol for the second replicate of the sample
NO3StandardRegressionSlope – is the slope of the regression line calculated from the standards in the NO3 protocol
NO3StandardRegressionIntercept – is the intercept of the regression line calculated from the standards in the NO3 protocol
NO3ppmSample1 – NO3 concentration in ppm calculated from the standard regression line for the first replicate of the sample. Is = (NO3Absorbance1 * NO3StandardRegressionSlope) + NO3StandardRegressionIntercept
NO3ppmSample2 - NO3 concentration in ppm calculated from the standard regression line for the second replicate of the sample. Is = (NO3Absorbance1 * NO3StandardRegressionSlope) + NO3StandardRegressionIntercept
NO3ppmSampleAverage – Is = Average(NO3ppmSample1, NO3ppmSample2)
NO3DilutionFactor1 – the dilution factor of the soil extraction procedure. Is = (MassOfSoil + 30 mL of extractant)/MassOfSoil. The number is unitless and should be between 2 and 3.
NO3DilutionFactor2 – the dilution factor for combining the sample with the reagents. The number is unitless and should be 2 for the NO3 protocol.
NO3DilutionFactor3 – the dilution factor for samples that were diluted because of NH4 concentrations above 3 ppm. If samples were not diluted in this step the number is 1. If they were diluted to half of the previous concentration then the number is 2. If they were diluted to one-third of the previous concentration the number is 3.
NO3ConcentrationSoilPpm – This is the concentration of NH4 in the soil in ppm. Is = NH4ppmSampleAverage * NH4DilutionFactor1 * NH4DilutionFactor2 * NH4DilutionFactor3.
This is the last column in the RAW data table. The raw data are used to calculate net N mineralization and net nitrification by subtracting the initial values from the incubated values. For net N mineralization we use the sum of NH4 and NO3 and for net nitrification we use only NO3
Notes and comments about the data:
Comment on data quality:
Use Restrictions: