Calcareous soil definition from the hydraulic and physical point of view [electronic resource].

Includes references.

Calcareous soils are of a wide occurrence under arid and semiarid climates, where the presence of CaCO) are in considerable amounts. These soils cover more than one million feddan of agricultural soils and more than 30% of desert soil in Egypt. One hundred and twenty soil samples were chosen from sixty soil profiles representing a wide range of CaCO) content and different textural classes were chosen in this study. The total and active CaCO) content were determined. Different physical and hydraulic properties were determined including, bulk density, aggregates size distribution, retention moisture characteristics, pore size distribution, infiltration rate, and saturated hydraulic conductivity. A definition of the studied calcareous soils was found OU!. These soils can be defined from the hydraulic and physical point of view as the soils which contain more than 16, 15, and 16% total CaCO) content or more than 5,4, and 6% active CaCO) content in their relation to basic infiltration rate (BlR), saturated hydraulic conductivity (Ks) and the soil moisture constants. Generally, these soils can be also defined as the soils which contain more than 14 - 17% total CaCO) or 4 -- 7% active CaCO,. in relation to the whole soil hydraulic properties.

Summary in Arabic.

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