Irrigation Method as a Determinant of Large Pore Persistence and Crust Strength of Cultivated Soils
1975
Kemper, W. D. | Olsen, John S. | Hodgdon, Alan
Air-dried soils were wetted by flooding, immersion, slow immersion and capillary action; these actions resulted in successively slower rates of wetting. In general, slower rates of wetting left larger portions of the soil volume in large size pores. Slow capillary wetting of a weakly structured soil allowed retention of more large size pore space than was observed in a well structured soil that was wet rapidly. Modulus of rupture was determined on dried soils which had previously been wet by rapid immersion, capillary action, and capillary action followed by immersion. Breaking strength was much greater when those soils had been wet by rapid immersion than when wet slowly by capillary action. Immersion following capillary wetting resulted in soils with intermediate breaking strengths. A preliminary study on corn (Zea mays L.) seedling emergence showed that the range of soil strengths resulting from these irrigation methods on a weakly structured soil was sufficient to give < 50% emergence (flooding) up to essentially 100% (capillary wetting).
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