Nitrate accumulation in the soil affected by nitrogen fertilization

Szováti K., Füleky Gy., Tolner L.

Department of Soil Science and Agricultural Chemistry, Szent István University,

H-2103 Gödöllő, Hungary

Keywords: fertilization, long term experiment, nitrate-N, soil

ABSTRACT

Numerous studies have shown that nitrate movement in the soil follows water movement, and increased downwards water movement from the top soil increases nitrate leaching losses and groundwater pollution, too. With very high fertilizer nitrogen application rates, the proportion of the applied nitrogen taken up by the plant decreases, and the residual fertilizer nitrogen in the soil will be vulnerable to leaching.

Field experiment was started at Szárítópuszta, an experimental station of Gödöllő University Agricultural Sciences ii-i 1970, where the nitrate movement in a brown forest soil was examined as affected by nitrogen fertilization. The study showed that increasing rates of nitrogen fertilizer caused nitrate downward movement.

The object of present study is to analyse the accumulation of nitrate-N in deeper soil horizons. Results showed that the nitrate-N content of the 0-3 meters soil profile decreased by the year of 2003, however at 0 and 90 kg N/ha former fertiiizer rates the nitrate-N content of the soil increased. The accumulation ceased, the nitrate content showed equable distribution in the 0-3 meters plots.