Effect of steel converter slag as iron fertilizer in some calcareous soils

摘要

The possibility of using converter slag as an iron (Fe) fertilizer in some calcareous soils was investigated. Slag used contained 16.83% Fe2O3 and 6.87% FeO plus a relatively large amount of calcium, silicon, phosphorus, and manganese. An incubation study was conducted with 3 calcareous soils for up to 60 days and the treatments included various amounts of slag (alone and mixed with elemental sulfur and alfalfa powder). Results showed that application of slag increased ammonium bicarbonate-diethylenetriaminepentaacetic acid-extractable Fe and pH in soils. The pot experiment was conducted with two different calcareous soils and corn (variety 647 Single Cross) as test plant. Treatments included various mixtures of converter slag with alfalfa powder, as well as ferric ethylenediaminedi(o-hydroxyphenylacetate). Results showed that application of 0.5 and 1% converter slag (based on soil dry mass) remarkably increased shoot dry matter and Fe, Mn, K, and P uptake. In general, there is a promising potential for converter slag to be used as an inexpensive source of available Fe for correction of Fe chlorosis in different crops in calcareous soils. This, however, needs further studies in the field and with various crops to determine the correct rates and to study the residual and environmental impact of application of this material to the soil.