島根県耕作地土壌の理化学的性質

その他

Some physical and chemical properties of the farm soils in Izumo district, were measured and the average results are as follows :
1. Mechanical analysis :
<tt>
──────────────────────────────────────────
Soils │ Coarse Sand │ Fine Sand │ Silt │ Clay │ Siol Class
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Paddy │ 28.28 (%) │ 30.04 (%) │ 19.61(%)│ 20.18(%)│ Sandy loam
──────────────────────────────────────────
Field │ 28.61 (%) │ 23.87 (%) │ 17.98(%)│ 29.67(%)│ Loam
──────────────────────────────────────────
</tt>
2. True specific grayity :
Paddy soils 2.51
Field soils 2.61
3. Apparent specific gravity :
Paddy soils 1.06
Field soils 1.12
4. Porosity :
Paddy soils 57.98%
Field soils 57.39%
5.Water capacity :
Paddy soils 51.62%
Field soils 45.97%
6.Total nitrogen :
Paddy soils 0.91%
Field soils 0.91%
7. Humus :
Paddy soils 3.37%
Field soils 4.01%
8. Exchange acidity (y_1) :
Paddy soils 3.80
Field soils 4.87