The objective of this study was to assess the influence of pipe drainage and increasing application of nitrogen fertilizers on leaching of nitrates from soil in winter barley and maize production. A field trial was conducted in the period 2000-2002 on hydroameliorated gley amphigley soil, at the agroecological station Kapelna in the easter Drava basin, in Croatia. The maine research factor was soil drainage, at two levels, drained and undrained soil. The subfactor was nitrogen fertilization, at four levels, 111, 172, 232 and 293 kg N/ha for winter barley, and 147, 174, 201 and 228 kg N/ha for maize. Significantly lower concentrations of nitrates were determined in the plough layer of drained soil compared to undrained soil as a consequence of more intensive leaching. Increase in fertilizer rates applied to winter barley from 111 do 239 kg N/ha led to an increase in annual leaching of nitrogen with percolating water from 18.6-42.1 kg N/ha. Increased nitrogen fertilization of maize from 147 to 228 kg N/ha was accompanied by an increase in nitrogen leaching from 5.3 to 13.2 kg N/ha. Average percentage of nitrogen leached in winter barley production was 15.6% of nitrogen added with fertilization, while 5.1% was leached in maize production.

Poljoprivreda

Rad je prezentiran na skupu VI. Alps-Adria Scientific Workshop, održanom 2007.g. u Obervellachu, Austrija.