Top right. - Measurement of saturated hydraulic conductivity (Ksat) by Amoozemeter (Ksat Inc., Raleigh, North Carolina) for a pedon of Talos soil at White Sands Missile Range, New Mexico. Bottom right. – Chemical analysis of soil samples using the HACH Kit (HACH Co., Loveland, Colorado). Mention of a trade name does not constitute a warranty of the product by USDA nor does it imply endorsement by USDA.
NONDISCRIMINATION STATEMENT
PREFACE
This manual and the “Kellogg Soil Survey Laboratory Methods Manual” (Soil Survey Staff, 2014b) cover many of the same types of analyses, and as such, both manuals serve as companion manuals to the “Soil Survey Laboratory Information Manual” (Soil Survey Staff, 2011 ), which describes the use and application of soil characterization data in more detail to maximize the user's understanding of this data. Even though the manual described herein contains descriptive terms or interpretive classes commonly associated with ranges of particular data. elements, this document, such as the “Information Manual for Laboratory Soil Research”. The field procedures for site and pedon description and sampling described herein are based on a number of sources, including but not limited to the “Kellogg Soil Survey Laboratory Methods Manual” (Soil Survey Staff, 2014b), the “Soil Survey Manual”. Soil Survey Division Staff, 1993), the “Field Guide for Describing and Sampling Soils” (Schoeneberger et al., 2012), and the “Handbook of Soil Survey.
The analytical procedures described here to characterize the physical, chemical, biological and mineralogical properties of a soil, as well as the analysis of water and plant samples are followed by a number of references, including but not limited to the "Manual of Survey Laboratory Methods of Kellogg soil" (Soil Survey Staff, 2014b). Other procedures are from peer-reviewed literature (e.g., Soil Science Society of America), methods specified in Keys to Soil Taxonomy (Soil Survey Staff, 2014a), or methods developed by established laboratories, public and private for the analysis of soil, water, and plant samples (eg, USDA Kellogg Soil Survey Laboratory, HACH and LaMotte Companies, and Ksat Inc.). Those analytical kits and supplies (eg, calcimetry and reactive carbon) associated with development at the National Soil Survey Center (NSSC), Kellogg Soil Study Laboratory (KSSL), and.
Refer to the USDA-NRCS “Soil Survey Office Laboratory Safety Guide” (2009c) and the “Material Safety Data Sheets and Rated Chemical Disposal Procedure” (2009a). Technical assistance on laboratory safety and quality control and standardization procedures is available upon request from the National Soil Survey Center, Kellogg Soil Survey Laboratory.
CONTRIBUTORS
ACKNOWLEDGEMENTS
USER’S GUIDE
FIELD ASSESSMENT AND SAMPLING STRATEGIES 1 Soil Survey 1 Soil Survey
- Field Sample Collection and Preparation
- Other Sampling Strategies
- Composite Random Sampling 1.2.8 Diagonal and Zigzag Sampling 1.2.8 Diagonal and Zigzag Sampling 1.2.9 Benchmark Sampling
- Landscape Directed Sampling 1.2.11 Grid Sampling 1.2.11 Grid Sampling
- Field Assessment
- Salinity, Sodicity, and pH
- Soil Fertility and Plant Nutrition
- Laboratory Sample Collection and Preparation
- Soils
The analyst and reviewer of data assumes that the sample is representative of the soil horizon. The depth and width of the pit depends on the soil material and the purpose of sampling. Using acetone upwind of a location helps prevent fumes from collecting at the bottom of the well.
Mark the appropriate cell on the inside of the box lid to determine the soil survey number and horizon (zone) for the lump. Label the top of the box to identify the type of sample (bulk density or thin section) and the corresponding soil survey numbers and horizons (zones) for the samples. Place a clip on the top of the core, place the core in a plastic bag and insert the bag into the cell in the lump box.
Refer to section 3.2.2 of this manual for a discussion of the analysis of particles >2 mm. Refer to Peck et al. 1977) for detailed description of soil testing methodology and correlation and interpretation of analytical results.
CONVENTIONS
- Data Types
- Size-Fraction Base for Reporting Data
- Soil Sample Weight Base for Reporting Data
- Significant Figures and Rounding
- Data Sheet Symbols
The air-dry/oven-dry (AD/OD) ratio calculation is used to adjust the AD results based on the OD weight and, if required in a procedure, to calculate the sample weight that is equivalent to the required OD weight of earth. . The AD/OD ratio is converted to a water of crystal basis for gypsiferous soils (Nelson et al., 1978). Calculation of the field moisture/oven dry (FM/OD) ratio is used to adjust the FM results based on the OD weight and, if required in a procedure, to calculate the sample weight that is equivalent to the required weight of land OD. .
Refer to sections and 3.5.3 of this manual to calculate the AD/OD and FM/OD ratios and the correction for water of crystallization respectively. FM weight is defined herein as the sample weight obtained without drying prior to laboratory analysis. In general, these weights reflect the water content at the time of sampling.
If a value is reported as 19.4 units, 0.4 is not certain, i.e., repeated analyzes of the same sample will vary by more than one-tenth but generally less than a whole unit. The data sheet symbol convention should be clearly specified in the field evaluation data.
SOIL PHYSICAL ANALYSES
- Soil Morphology
- Color
- Structure and Consistence
- Podzol and Podzolic Soil Development
- Particle-Size Distribution Analysis
- Particles <2 mm Application, General Application, General
- Particles <2mm
- Particles >2 mm Application, General Application, General
- Particle-Size Distribution Analysis
- Particles >2 mm
- Bulk Density
- Field-State
- Water Retention
- Desorption on Hectorite
The original Singleton blade is usually placed on the ground or on the ground surface. A clay skin usually confirms the gross irregularities of the surface, but fills in the minor ones. Use an automatic pipette to remove the particle-free liquid from the top of the soil.
P= C/Co x 100, P is the percentage of the total for the given time interval, and Co is the weight of the dry soil sample. This procedure is used to determine mass percentages of fractions >2 mm by weighing in the field. Soil variability and sample size affect weight determination of particles >2 mm.
Add this to the weight of the >20mm material to obtain the air dry weight of the field sample. Estimate or determine the bulk density of the moist (near field capacity) fine earth fabric. Indicate the weight and volume percentages of the separately determined fractions >2 mm and the total fraction >2 mm.
This procedure is used to determine weight percentages of the >2-mm fractions by field and laboratory weighings. In the field or in the laboratory, the sieving and weighing of the >2-mm fraction is limited to the <75-mm fractions. Less accurately, the 20 to 75 mm fraction in the field is estimated as a volume percentage of the whole soil.
Weight measurements of 20- to 75-mm fractions in the field are more accurate than visual estimates of volume. Use the following equation to determine the volume of the <2 mm fraction per unit volume of total soil. The bulk density of soil in a sample is the ratio of the mass of solids to the total or total volume.
Multiply the change in distance by the inside cross-sectional area of the ring to obtain the volume of the soil (Ve).
Clay Pyro-
Dry the sample in an oven overnight at 110°C, or dry for 15 minutes after the soil appears "dry," either under a 250-watt infrared lamp 4 inches from the soil or on a heating surface of a gas or electric element held at 135 °C.
Dominant clay
- Field-State
- Water Retention
- Plant Available and Unavailable Water Estimates, Volume Basis
- Water State Classes
- Ratios and Estimates Related to Particle-Size Analysis, Bulk Density, and Water Retention Density, and Water Retention
- Ratios and Estimates Related to Particle-Size Analysis, Bulk Density, and Water Retention
- Coefficient of Linear Extensibility (COLE) Application, General Application, General
- Coefficient of Linear Extensibility (COLE)
- Water Flow
- Single-Ring Infiltrometer
- Double-Ring Infiltrometer
- Amoozemeter, Compact Constant Head Permeameter
- Soil Stability, Dispersion, and Slaking
- Aggregate Stability
- Slaking as Measure of Soil Stability when Exposed to Rapid Wetting
- Dispersion as an Indicator of Soil Sodicity and Permeability (Crumb Test) Test)
- Dispersion, Electrical Conductivity (EC), pH as Indicators of Soil Salinity, Acidity, and Sodicity Salinity, Acidity, and Sodicity
- Slaking (Disaggregation) for Identification and Semiquantification of Cemented Materials Cemented Materials
- Soil Water Repellency
- Waterdrop Penetration Time (WDPT)
- Mini-disk Infiltrometer (MDI)
- Engineering Tests
- Atterberg Limits
- Unified Soil Classification System Using Field Procedures
Unavailable water is an estimate of the water that must be subtracted from the water content of the field to obtain plant-available water. The moisture content is expressed as the ratio between the weight in air and in the oven (AD/OD). The AD/OD ratio is corrected on the basis of water of crystallisation when the gypsum content of the soil.
The first inch of water moistens the soil, and the second inch gives a better estimate of the soil. The saturated hydraulic conductivity of the surface layer can be estimated when the water flow rate in the inner ring is stable. Prevent leakage around cylinder walls by lightly tapping the contact between the ground and the inner surface of the cylinder.
However, the lowest part of the borehole (the part to be sunk; usually 15 cm + 5 cm buffer) should be a standard 6 cm diameter. Always measure the water depth by aligning the same point on the dipstick with the ground and surface reference plane (e.g. Amoozemeter base plate). In fact, the method described in this section captures the greater part of (water-persistent) macroaggregates.
Try to get all the soil through the sieve by gently pressing the soil through with your thumb. Add water to a 5-gallon bucket (or a smaller straight-sided bucket that will fit the sample) and mark the tip of the water surface on the bucket. It may be necessary to heat the solution during quenching due to the slow solubility of silica.
Refer to Robichaud et al. 2008) for discussion of the categorization of WDPT based on various developed water repellency classes. Water droplets inside the rectangle are beaded on the surface; drops outside the rectangle penetrated the ground. Hold the top of the infiltrometer so that the water surface in the main chamber is at eye level and record the initial volume (ml).
At the end of 1 min, remove the infiltrometer from the soil and hold the top of the tube so that the water is at eye level. This test is performed on that part of the soil that has particles that exceed No.
