Effects Of Different Zootechnical Digestates On Fertilization And Nitrogen Leaching

The aim of the work was to verify the fertilizing effect of three types of zootechnical digestates on the ryegrass culture in comparison to mineral fertilization and to evaluate the risk of nitrogen leaching. Plants were grown in pots and five harvests were made from March to May. In the same period, 20 days after sowing, six rains were simulated once every 10 days. At each harvest plant biomass production and nitrogen uptake were determined. At each rain, the concentration of nitrogen in the leached was analysed. Results showed that the differences in chemical composition among three zootechnical digestates influenced both nitrogen uptake and nitrogen leaching. The highest loss of nitrogen by leaching was found in the soil treated with bovine digestate. The digested pig slurry-solid fraction had a greater potential as soil amendment than the liquid fraction, whereas the latter had a greater potential as fertilizer than the former.