Baseline Soil Sampling and Analysis- GLBRC BCSE, Scale-Up, & Marginal Sites

Active

Replaces Baseline Soil Sampling and Analysis- GLBRC Intensive Site

In use from 2010-03-01

Abstract

Surface Soil Sampling in Marginal Sites

Every 3 years, surface soil samples will be taken at all the marginal sites. Using a push corer (2 cm diameter), take four cores in each split plot (2 cores at each of 2 locations), to a depth of 15 cm. Composite the cores by split plot, sieve (mesh 2 mm diameter in WI; 4 mm diameter in MI), air dry, and send to the MSU and UW Nutrient Labs. Samples will be analyzed for % carbon, % nitrogen, pH, lime index, phosphorus, potassium, calcium, magnesium, and cation exchange capacity.

Fall Surface Soil Sampling in Scale-Up Sites

Fall surface soils samples are taken to 25 cm with a push probe (2 cm dia.) at each of ten sample stations. In the lab, soils are weighed, sieved, and subsampled to provide inorganic nitrogen and gravimetric moisture. An additional sample is sent to the MSU and UW Nutrient Lab for a standard suite of agronomic soil analyses (pH, lime index, phosphorus, potassium, calcium, magnesium, and cation exchange capacity).

Spring Surface Soil Sampling in Scale-Up Sites

Spring surface soil sampling has been discontinued at the scale-up sites, as of 2014. Prior to 2014, samples were taken each spring with a push probe (2 cm dia.) to 25 cm depth at each of the ten sample stations. In the lab, soils were weighed, sieved, and subsampled for inorganic nitrogen and gravimetric moisture.

Deep Soil Sampling in Intensive and Scale-Up Sites

Soil cores to 1 m depth are taken once every 5 years to follow long-term carbon change. Intact cores (7.6 cm dia.) are taken with a hydraulic probe (at KBS: Geoprobe model 540MT, Geoprobe Systems; Salina, Kansas; at Arlington: Giddings probe, Giddings Machinery Co, Windsor, Colorado) at each of 3 sampling stations (one core/station). In 2008, deep cores were taken in late spring/summer at KBS and in the fall at Arlington. In 2013 and going forward, deep cores were taken in the fall at both sites. In 2013, additional surface cores were taken at KBS, to assess the effect of season. Similarly, at the scale-up sites, cores were taken in spring 2009 and in the fall of 2014, with additional surface samples taken in the spring 2015, to assess the effect of season. For the row crops, cores are taken between the rows. Cores are refrigerated until analyzed. Cores are cut by specific depth intervals (0-10, 10-25, 25-50, and 50-100 cm), and analyzed for bulk density, soil moisture, total nitrogen and carbon, and soil chemistry. The initial sampling also included cation exchange capacity, depth to major soil horizons (Ap, Bt, and Bt2 at KBS), and soil texture for each depth interval, composited by plot (intensive site) and by station (scale-up site).

Surface sampling in BCSE Plots

Starting in 2013, soil cores to 25 cm depth are taken 3 times per year: once prior to planting of annuals (May), once after fertilizer application (June), and once just before harvest (October). Cores are taken with a push probe (2 cm diameter) at each sampling station in all plots. Each plot has 3 sampling stations and 2 cores are taken at each station and composited. In the lab, samples are weighed, sieved, and sub-sampled for inorganic nitrogen and gravimetric moisture.

2010-2012: Every two weeks, soil cores to 25 cm depth (KBS) or 15 cm depth (Arlington) are taken with a push probe (2 cm diameter) at each sampling station in all plots, following the same procedures described above for 2013.

In 2009 only, resin strips were used instead of push cores. Resin strips (2.5 × 10 cm) were placed in the field on a monthly basis from March to November. Cation and anion strips were placed at each of the three sample stations and left for 4 weeks.

In addition, every fall, samples are taken from all main and microplots, using the sampling procedure described above. These samples are sieved, dried, and sent to MSU and UW Nutrient Lab for a standard suite of agronomic soil analyses (pH, lime index, phosphorus, potassium, calcium, magnesium, and cation exchange capacity).

Protocol

Sample Locations

Within each intensive plot, there is a stratified random placement of three sample stations. Within each scale-up field, there are 10 sample stations. Sampling by station increases the potential for identifying early treatment differences but care must be taken to avoid taking more than one sample from a particular spot and to avoid excessive plot disturbance. Table 1 provides suggested locations, which must necessarily be flexible to allow for the need to retake cores that encounter rocks or excessive compaction.

Table1: Location of sampling within the plot with reference to stations, taking into consideration biomass sampling locations and the need to avoid repeating exact locations each year.

Year Spring Fall Deepcore
2008 1mN, 1mE 1mN, 2mE 4mS, 1mE
2009 1mN, 1mW 1mN, 2mW
2010 1mS, 1mE 1mS, 2mE
2011 1mS, 1mW 1mS, 2mW
2012 1mN, 1mE 1mN, 2mE
2013 1mN, 1mW 1mN, 2mW 4mN, 1mE

Materials (Does not include materials for specific analyses)

  1. Geoprobe (model 540MT, Geoprobe Systems; Salina, Kansas) or Giddings probe (Giddings Machinery Co.)
  2. Plastic bags (pre-labeled)
  3. Meter Stick
  4. cm ruler
  5. 4mm sieve (treatment specific)
  6. Data Sheets
  7. Drying Oven @ 60 ° C
  8. Balance (e.g. Mettler PJ3600)
  9. Soil Grinder
  10. Pint and Quart Canning Jars (pre-labeled)

Soil Inorganic Nitrogen

Follow LTER protocol: KBS021-prot03, V1

Gravimetric Moisture

Follow LTER protocol: KBS015-prot01, V1

Bulk density

Follow LTER protocol: KBS026-prot01, V1 taking into consideration differences in soil core diameters and depth increments. For measuring bulk density in deep core samples follow LTER protocol:

Soil pH

Follow LTER protocol: KBS028-prot01, V1

Soil Organic Carbon and Nitrogen

Follow LTER protocol: KBS024-prot01, V1

Agronomic Soil Analyses (N, P, major cations)

Samples are sent to Soil and Plant Nutrient Laboratory Department of Crop and Soil Sciences, Michigan State University, East Lansing.

Microbial biomass (Carbon and Nitrogen)

Follow LTER protocol: KBS011-prot01, V1

Ion Exchange Resin Strips for Nitrogen Availability in Soil

Follow LTER protocol: KBS033-prot02, V1

Soil horizonation

Major soil horizon depths (cm) are estimated by visual differences in color and texture. Generally 3 horizons are identified, as well as any sand intrusions.

Soil texture

Follow LTER protocol: KBS000 V1 after compositing soils by plot.

Carbonate Detection

Follow LTER protocol: KBS058-prot1 V1

Cation Exchange Capacity

Composite samples by plot (25 gm) and depth increment are sent to Soil and Plant Nutrient Laboratory), Department of Crop and Soil Science, Michigan State University, East Lansing.

Hydraulic Conductivity

Calculated by modeling equations.

Archiving

For annual fall sampling: Remaining soil after subsampling is dried and placed in glass jars after compositing by plot. Jars are labeled with sample date, depth increment, and treatment code in order of T-R- D-, where T = treatment number, R = replicate, and D = depth.

For deep core samples: Each dried individual horizon section is ground and stored in glass jars; cores are not composited. Jars are labeled with sample date , treatment code as T-R-S where T = Treatment #, R = Replicate #, S = Station # and depth (0-10 cm, 10-25 cm, 25-50 cm and 50-100 cm)

Author:

Datatables