Influence of long-term fertilization on the selenium content of calcareous chernozem soil.

Available data on the selenium (Se) content in Yugoslavian soils indicate that the element is present in small amounts (< 500 microg/kg in Se-deficient soils). There are no data on the effect of various fertilizers on the Se content in Yugoslavian soils. In our study, we examined the effect of the long-term application of mineral and organic fertilizers (farmyard manure and cornstalks) on the content of Se in calcareous chernozem soil. The experiment of the Maize Research Institute in Belgrade was set up in 1971 and soil samples were examined by chemical analysis after 23 years. The following important conclusions can be drawn based on the analytical data obtained. The total content of Se in the investigated experimental variants in calcareous chernozem soil ranges from 166 to 593 microg/kg. All the variants had a higher content of Se than soil samples taken before the experiment was set up. Comparison with the control (variant without fertilizers) indicated that the Se content increased in the experimental variants where farmyard manure had been applied. This effect was noticed to a depth of 80 cm. Application of farmyard manure should be considered as a means of increasing the levels of Se in Se-deficient soil. Correlation coefficients between total Se content in the soil and some important agrochemical properties of the investigated soils are presented in this paper.