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Zinc deficiency, in many cases, is closely related to organic matter decomposition. DeRemer and Smith (1964) studied the effects of decomposing sugar beet tops on the reactions of Zn65 in a Portneuf soil. They found that with time the Zn65 associated with lime minerals, eschangable, and water soluble fractions of the soil decreased, while that found with the organic and mineral fractions increases. This increase in the mineral fraction is of particular interest, since the majority of the Zn65 was found to be with this fraction after a period of time. They also showed that the increase in Zn65 associated with sand-silt size fraction after a rough separation was greater than with the clay fraction. Smith, Henry, and Shourky (1965) studied the Zn65 associated with the organic fraction as it changed with time. They found that the Zn65 associated with the fulvic acid increased rapidly during early incubation periods, but in the later incubation periods had decreased considerably and was found in the mineral fraction. Shourky (1966), in a study of the effect of decomposing organic matter on the available Zn65 as determined with various reagents, found that after 12 weeks incubation a great portion of the Zn65 was found associated with the mineral fraction. |
