Collecting Samples for Reference or

Characterization Analysis

Michael A. WilsonResearch Soil Scientist

Soil Survey Research and LaboratoryLincoln, NE

Rationale

• Collection of soil samples for analysis—

Single step of a multifaceted process.

• For proper collection, must understand:

timing for project completion types of projects the complete package long-term utilitarian nature of data

OBJECTIVES

Upon completion of this module, the student should be able to:

Understand the importance to sample for multiple objectives

Differentiate between types of projects

Describe process of work plan submission to project completion

List important components of a NCSS/NRCS characterization dataset

REFERENCES• KSSL Sample Submission Information; Zip file

located at: http://www.nrcs.usda.gov/wps/portal/nrcs/main/soils/research/lab/guide/

• Burt. R. (ed.) 2014. Soil Survey Laboratory Methods Manual. Soil Survey Investigations Report No. 42. Version 5.0. U.S. Govt. Print. Office, Washington, DC.

• Soil Survey Staff. 2009. Soil Survey Field and Laboratory Methods Manual. Soil Survey Investigations Report No. 51, Version 1.0. R. Burt (ed.). U.S. Department of Agriculture, Natural Resources Conservation Service

• National Soil Survey Handbook

Purposes for Sampling

• Supplement field data with laboratory info on soil properties and behavior.

• Develop field and laboratory methods

• Replace or verify estimated data• Develop soil interpretations and

models• Investigate soil genesis and

landscapes.

Observation and Measurement

TYPES OF PROJECTS involving laboratory

analysisREFERENCE• Limited sample numbers and analyses• For background information

CHARACTERIZATION• Extensive or important soils in survey area• Collect and analyze all horizons in pedon• Comprehensive analysis of horizon

GEOMORPHIC AND STRATIGRAPHY PROJECTS• For relationship of soils, landforms, and statigraphy of parent materials• May involve multiple pedons in catena defined by morphology and/or hydrology

RESEARCH• Specialized long or short term projects• Unique sampling scheme to address objectives

OTHER• Geophysical

REFERENCE CHARACTERIZATION RESEARCH

Increasing personnel, time, complexity, cost

Project requests are evaluated and prioritized; may/may not be accepted based on importance and resources

Timeline for Receiving Lab Data

May 2014

May

2015

May 2016

Aug

NOV

Nov

You

decid

e

to s

am

ple

Request for assistancesent to NSSC; develop workplan

Fiscal year begins

Snow

ProjectComplete

1.5 years---plan accordingly

Partial DataAvailable

Samplessent to SSL

SubmitWork plan

WORKPLANSfor sampling

• Can be initiated by any NCSS personnel (working through the State/Regional office)

• Workplan development is best a cooperative effort

• Workplan documentation includes:

• survey area (geology, geomorphology, soils, climate, ect.)• project background (literature review, available data)• objectives – statement of problem• justification• resources needed• personnel involved• sampling scheme• analyses• data usage – need for information• See Exhibits 631-3, 4, and 5 in the NSSH.

Utilitarian nature of Characterization Data

Each set of data has multiple users over time

Soil survey characterization

MLRA Update

Teaching

Study of Soil mineralogy

Global Climate Study

DevelopingInterpretations

CharacterizedPedon

Carbon Sequestration

Each pedon is a dataset composed of:

Site information• Location• Climate • Geomorphic information• Parent material/Bedrock

Pedon Data• Observation method• Taxonomic classification• Detailed morphology

Laboratory Data• Bulk density and water

retention• Routine chemistry and particle

size data• Selective dissolutions• Mineralogy

FOCUS ON COMPLETENESS—

description, sampling, and

analyses of horizons

All these data are Characterization Data

FOCUS ON PEDONS REPRESENTATIVE OF MAJOR SOILS AND

GEOGRAPHIC COVERAGE

BENCHMARK

“Full data on a few well-selected soils over a range of conditions are more useful than a few data on many soils.”Kellogg, 1962: The Place of the Laboratory in Soil Classification and Interpretations

PEDON SAMPLING TECHNIQUES

Excavated pits• Best method for observation of

properties• By hand or backhoe• Dug through solum to parent material (2-m)

Hydraulic Probe• Trim off exterior to remove oil or other contaminant• Compare core length to hole depth• Split core to describe

Bucket auger• Identification and mixing of horizons is a problem• Sample generally of less quality for analysis

REMEMBER SAFETY!• Shoring Equipment

• T-Shaped pit• Sloping side walls• Keep spoil pile >2 ft from side

• 1 ft3 of soil can weigh > 125 lbs

• 1 m3 (35.3 ft3) of soil can weigh > 3,000 lbs.

http://www.osha.gov/dts/osta/otm/otm_v/otm_v_2.html#6

PERMAFROST-AFFECTED SOILSIce Auger

Human-Altered Human-Transported SoilsNew York City

What field data and

samples are important to

collect?

Coeur d’AleneRiver, Idaho

Potentially Contaminated

Soils

Is it safe to sample?

Know your hazards!

Sampling Schemes • Representative Pedons• Grab (?) Samples• Satellite samples• Horizons vs fixed depths• All horizons, selected horizons, or composite

sampling

“Our results implied that sampling by depth increments is favorable for the detection of regional OC stocks and that sampling by soil horizons should be used for the study of pedogenic processes which control OC stocks in soil.

Differences in OC stocks among soil groups are more pronounced if horizons are considered, which shows that mixing of soil horizons by fixed depth increments destroy important pedogenetical information. “

Grüneberg et al., Geoderma 155 (2010) 426–433

NON UNIFORM, NON HORIZONTAL HORIZONS

• Vertisols• Permafrost Affected Soils• Animal disturbance• Degrading argillics (Glossic)

Wavy boundariesPockets of materialDisplaced materialDiscontinuous horizonation

Describe and samplethe material

OTHER SPECIAL SAMPLES

Organic soils• From pit (if drained) or Macaulay peat sampler if submerged

Sulfidic soil materials• Generally in intra-tidal zones and saturated• Collect sample and seal to eliminate air (mason jar or plastic bag); store on ice or freeze• Analyze “oxidized pH”

Soil Biology• Above ground biomass-id and clip all veg in 50X50 cm area• Surface litter – 50X50 cm area• Root biomass – sample by horizon for 1 m2, separate by root size• Microbial biomass – soil, transport under ice or refrigeration (4 C)

SAMPLES COLLECTED— for all horizons for

complete characterizationBulk sample • 3 kg• < 20-mm fraction

Bulk density clod• three egg shaped, fist sized clods • dipped in saran

Natural fabric• for thin section and/or permanent storage• oriented with staple• similar in size to BD clods

What were they thinking?

Sampling for Bulk Density

Clods of natural fabric

Compliant Cavity

Cores

Examples

Not all clods are created equal!

Issues:• Loose topsoil (Ap)• Sands• Rock Fragments• Shrink Swell clays• Organic rich soils• Wet or frozen soils• Size

SOILS WITH ROCK FRAGMENTS

• Weigh all material <75-mm (weigh 60-100 lbs rock+soil for accurate measure)

• Volume estimate for rock fragments 75-200 and > 200 mm

• Ship > 3kg if percent 2-20-mm fraction is high (e.g., 2-3 bags)4 kg is approximately 1 gal material

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Col. 16 (0.1 to 75 mm) = Used for silty/loamy break in family particle size

Col 17 (wt% >2-mm) = Coarse fragments on a weight basis; based on values in pedon description and lab measurement for

2-20 mm.

Supplemental Tier 3; Col 1 = Coarse fragments >2-mm on volumetric basis

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2-5 mm Fine gravels5-20 mm Medium gravels

20-75 mm Coarse gravels

75-250 mm Cobbles250-600 mm Stones>600 mm Boulders

Lab measures

Field measures -weight

Field measures -volume

Coarse Fragments on SSL Datasheet

Transmittal of Samples to SSL

• Refer to the instructions posted on the web: http://www.nrcs.usda.gov/wps/portal/nrcs/main/soils/research/lab/guide/

Transmittal of Samples to SSL

• All soil samples submitted must be accompanied by the standardized spreadsheets ‘KSSL Project Sheet’ and ‘KSSL Sample Submission’.

• Spreadsheets provide the lab with all information needed to process and analyze the samples.

• The ‘Sample Submission’ spreadsheet will aid in identifying the analytical data and correct soil description information.

• Printed copies of the project and analysis spreadsheets and pedon descriptions should be:

included with the samples and

Sent electronically to your Lab liaison.• • This spreadsheet will be the only acceptable

form of sample analysis request.

• Contact your KSSL liaison with any questions related to the documentation of submission process.

Transmittal of Samples to SSL

APHIS-Animal and Plant Health Inspection Service

• APHIS regulations for soils in areas with – Imported Fire Ant– Witchweed– Golden Nematode– Oriental Fruit Fly– Sudden Oak Death

• Nebraska Department of Agriculture (NDA) regulations for– Columbia Root Knot Nematode

• List of Regulated Areas in Part 2 of sampling instructions to determine if a sampling area is regulated. Contact Richard Ferguson, Larry Arnold or the appropriate NSSC Liaison if there are any questions.

REGULATED SAMPLES

APHIS Impacted Areas

• CALIFORNIA• COLORADO• FLORIDA• GEORGIA• IDAHO• LOUISIANA• MISSISSIPPI• NEVADA

• NEW MEXICO• NEW YORK• HAWAII• All Foreign

Countries• All other areas

outside of the CONUS except Alaska

CONTAINMENT forRegulated Bulk samples

• Primary container: a heavy duty plastic bag provided by the KSSL.

• Secondary container: a large heavy duty plastic bag provided by the KSSL.

• Tertiary container: A rigid outer container, a heavy duty cardboard box.

Pedon Descriptions into NASIS

• Pedon and site information from NASIS will be accessed directly by the Laboratory Information System

• This requires that NASIS Pedon and Site data be in NASIS and accessible to the KSSL

• Responsibility of field, state, or MLRA office to enter pedon descriptions prior to sample submission

Sample Preparation in the SSL

Common Procedures (Codes)• S = Standard air- dried

preparation• M = Standard moist preparation• H = histic or organic soil

preparation• K = crush 2-20 mm coarse

fragments to < 2-mm (e.g., SK prep)

• GP = mix and crush <20mm soil material (<2mm soil plus coarse fragments) to < 2-mm

Understand what happens to your samples!

Cr Horizons from one project in Montana

Do they slake in water? S vs GP prep?

SSL Project Analytical Report

• Sent to states and project/office leader for review

• Opportunity to verify classifications and analytical requests

CONCLUSIONS

• Plan ahead for laboratory analyses

• Sample important soils/sites that can address multiple objectives

• Be methodical and comprehensive in description, sampling, and analytical requests

• Complete the process—enter description, evaluate analytical requests, understand preparation