Efficiency of the use of neutralized phosphogypsum, phosphorite processing waste, in agriculture

Abstract

AbstractPhosphogypsum (PG), phosphorite processing waste, can be used in agriculture as a chemical ameliorant to eliminate soil degradation. But it has some disadvantages, especially acidity; therefore, the use of neutralized phosphogypsum (NPG) is proposed. The development of methods for the rational NPG use, both separately and in combination with mineral fertilizers, to improve soil fertility was the purpose of this study. The results of stationary field experiments to study the NPG effect on the fertility parameters of meadow chernozem soils are presented. For three years of the study, the portion of humic acids and the content of humic acids bound with calcium increased in the plow layer. Already in the first year of action, NPG decreased the soil acidity. Introduction of calcium into the soil with NPG stabilized the calcium regime and increased the absorption capacity by 3.2%–6.5%. The content of heavy metals was within the natural background and did not exceed the maximum allowable concentrations. No reliable increase in fluorine and strontium concentrations was revealed. On the whole, NPG use is environmentally safe; it improves soil fertility and quality of plant products.