Calcium and magnesium deficiencies in alkali soils
1946
Bower, C.A. | Turk, L.M.
Previous investigations have indicated that calcium deficiency may be responsible for the poor growth of plants when the soil or clay was artificially saturated with sodium to a high degree and when CaCO3 was absent. The results reported herein provide evidence which indicates that naturally occurring alkali soils, high in exchangeable sodium may not furnish an adequate supply of calcium to plants even though CaCO3 is present. The conditions required for calcium deficiency in noncalcareous soils appear to be a high percentage sodium saturation (40% or more). In the case of calcareous soils, a high pH value (above 9 or 9.5) seems to be an additional prerequisite. Under such conditions the solubility of soil calcium is usually very low. Evidence is presented which indicates that magnesium deficiency may also occur under soil conditions similar to those which cause calcium deficiency.
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