KBS044: Deep Core Bulk Density and Archiving
In use from 2001-01-01
Note: Due to the need to perform moisture and C/N analyses, samples must be weighed wet, sieved, mass of rocks measured and recorded before drying at 60 ° C for 48 hrs.
- Intact core sample
- # 10 and # 20 paper bags (pre-labeled)
- Meter Stick
- 4mm sieve (Treatment specific)
- Data Sheets
- Drying Oven @ 60 ° C
- Custom™ Soil Grinder
- Pint and Quart Canning Jars (pre-labeled)
- Pre-label paper bags with the appropriate information about the sample (e.g. date, plot, station, core#, horizon, variate)
- Delineate horizons (Ap, Bt, Bt2).
- Measure core height for each horizon.
- Carefully cut open core liner and remove the first horizon.
- Weigh first (A) core horizon section, record.
- Sieve A horizon, weigh rocks >4mm, record mass.
- Place sieved core section in labeled paper bag, discard rocks >4mm.
- Brush sieve and repeat procedure for all horizon sections.
- Place samples and 10 empty paper bags (for each size used) in drying oven at 60 ° C for at least 48 hours.
- Remove samples and paper bags from oven and allow to cool for at least 15 minutes.
- Weigh samples and paper bags. Determine soil mass by subtracting mean bag weight from the weight of the soil core + bag weight.
- Add weight of rocks to soil dry weight for total dry weight.
Bulk density (g/cm3) = W/V where W = total oven-dry weight in grams Dry weight of sieved soil + weight of rocks >4mm V = volume of core section in cm3 Cylindrical Volume = (π)(r2)h % Soil Moisture = ((TW – W)/W) * 100 where TW = Total wet soil weight in grams W = Total dry soil weight in grams + weight of rocks >4mm – bag weight
- Run entire dried individual horizon section through the Custom™ Soil Grinder.*
- Clean out grinder between each sample.
- Store ground sample in pre-labeled canning jar (pint for A and quart for B horizon).
- Archive jars in original jar boxes in order of T-R-S-C-H where:
T = Treatment# R = Replicate# S = Station# C = Core# and H = Horizon
*Deep core soil archived for 2010 was not ground.