Effect of Liming and Organic Matter Content on the Availability of Native and Applied Manganese

Abstract

AbstractA large amount of the soluble Mn added to soils was rapidly converted to nonexchangeable forms in both incubation and field studies. The addition of lime further decreased the amount of exchangeable Mn (NH4OAc‐extracted). The acid‐extractable Mn content of the soil showed no decrease at the end of 3 weeks' incubation but did after 6 weeks' incubation.The moisture content of the sample previous to extraction had an effect on the exchangeable Mn content. Less exchangeable Mn was extracted when the soil was kept moist after the sample had been taken than when it was first air‐dried. This effect was most pronounced on a high organic matter soil which had been limed.The addition of peat to a low organic matter soil increased the exchangeable Mn conent of the acid soil when maintained in a moist condition. The peat caused a decrease in the acid‐extractable Mn in the limed soil.