10.1 Introduction
10.2 Soil test methods for available P
10.3 Approaches for characterizing available P
10.4 P fractionation procedure
10.4.1 Materials
10.4.1.1 Extracting solutions
10.4.1.2 Reagents for P determination
10.4.1.3 Resin strip
10.4.2 Analytical procedures
10.4.2.1 P determination by the Murphy-Riley (1962) method
10.4.2.2 Determination of inorganic P on 0.5 M NaHCO3
and 0.1 M NaOH
10.4.2.3 Determination of total P in 0.5 M NaHCO3, 0.1 M NaOH,
and conc. HCl extracts (EPA 1971)
10.4.3 Extraction procedure
10.4.4 Interpretation and limitations
References
0.5 g土壌試料 | 水中において樹脂片(resin strip)で抽出 | Piの決定 | |
↓ | NaHCO3で抽出 | 炭酸水素塩(重炭酸塩、bicarbonate)で抽出可能なPt | 温浸(digest)、Ptの決定 |
↓有機物を沈殿 | Piの決定 | ||
↓ | NaOHで抽出 | OHで抽出可能なPt | 温浸(digest)、Ptの決定 |
↓有機物を沈殿 | Piの決定 | ||
↓ | 希塩酸(dil. HCl)で抽出 | Piの決定 | |
↓ | 濃塩酸(conc. HCl)で抽出 | HClで抽出可能なPt | 温浸(digest)、Ptの決定 |
↓ | Piの決定 | ||
土壌残渣(soil residue) | 温浸(digest)、Ptの決定 |