ABSTRACT

Several management measures are available for preventing, or at least minimizing, nitrate pollution of groundwater resulting from agricultural or waste disposal related practices. Efficient nitrogen fertilization is particularly important to sugar beet crops, as a deficiency of available nitrogen often limits yield, while an excess can result in unnecessary economic expenditures. Further, efficient fertilization is important to minimize energy input in crop production and to minimize additions of nitrogen that might contribute to pollution of groundwater. Slow-release nitrogen (SRN) fertilizers may be used to minimize nitrogen losses from soils subject to leaching. Conventional nitrogen fertilizers contain nitrate, urea, or ammonium ions, with the latter two sources being readily converted to nitrate by soil microorganisms. SRN fertilizers also convert urea and ammonium components to nitrate, but their conversion rate is low.