abstract: The process of soil eutrophication caused by nitrogen from mineral and organic fertilizers is discussed in the paper. Nitrogen utilization by plants in the first and second year following fertilization was determined. It was demonstrated that high nitrogen rates had a negative effect on the quality of potato tubers. Excessive accumulation of mineral N in the soil results in the loss of this element due to leaching. The level of N-NO3 leaching in the soil fertilized for 25 years was slightly higher after the application of organic fertilizers, compared with mineral fertilizers

keywords: mineral nitrogen, soil, plant, leaching

original in: Polish