Balance of mineral nutrients in [the waters of] the Usti nad Orlici region [Czech Republic]
1990
Damaska, J. (Vyzkumny Ustav pro Zurodneni Zemedelskych Pud, Prague (CSFR)) | Kastil, J.
Trials were performed for four years (1985 - 1988) in monthly intervals to study the changes in water chemism and outlet from the territory of the Usti nad Orlici district. Data on amount of precipitation water and its infiltrating by soil were determined by the network of precipitation measuring and lysimetric stations. Chemical analyses of water from waterflows were carried out regularly along with analyses of precipitation and lysimetric infiltrates, then annually were performed analyses from plants of lysimetric and microplot trials. Data on amount of fertilizers and calcium-magnesium compounds applied in the whole district were recorded continuously. Based on the experimental and statistical data, the balance of nutrients was elaborated for the whole district showing the slightly positive balance of N, P, K and S or negative one for Ca, Mg and Cl. High losses of nutrients caused by discharge exhibit rather high reserves of the intensification process of crop production within the district. It follows from the relative expression of the relationship of different balance components that mainly N, Mg, S and Cl penetrate from waterflows into the soil while P and K excesses remain fixed by the soil for the greater part. The larger part of nutrients in waterflows except N comes from non-agricultural resources.
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