Analytes Certified for in 2022
This method is required to adjust soil chemical results based on air-dry samples to an oven-dry (105oC)
basis. When the air-dry moisture content (M%) is known, the correction from air-dry
to oven-dry is as follows:
Oven-dry result = [Air-dry result x (100+ M%)]/100
Exchangeable bases - 1M ammonium acetate at pH 7.0.
This rapid method for exchangeable cations in non-saline acidic through to slightly alkaline soils has no pre-treatment for soluble salts. It should yield similar data to those of method 15A1, except it can overestimate exchangeable Ca in soils containing calcium carbonate.
Analysis of Mehlich 3 extract using inductively-coupled atomic emission spectroscopy (ICP-AES)
Microwave Digestion - closed system without HF, and final medium HNO3 and/or HCl. ICP-AES finish.
Microwave Digestion - closed system without HF, and final medium HNO3 and/or HCl. ICP-MS finish.
Finely divided dry sample. Dumas combustion.