Effect of organic manure and chemical fertilizer on nitrogen uptake and nitrate leaching in a Eum-orthic anthrosols profile

Distribution and accumulation of NO3-N down to 4 m depth in the soil profile of a long term fertilization experiment with organic manure and N and P chemical fertilizer were studied after 12 years, wheat and corn were planted in each year. The apparent N recovery decreased with increased N and P fertilizer. NO3-N was mainly accumulated in 0-1.2 m depth of the soil profile with a maximum of 34 mg N kg(-1) for the treatment with 120 kg N and 26 kg P per hectare, a secondary maximum of 7.2 mg N kg(-1) was found at 3.2 m depth in the same treatment. NO3-N accumulation in the soil profile was minimized in the trials with highest manure application. Nitrogen that was not recovered was leached as NO3-N deeper than 4 m depth, was immobilized in the profile or was lost by denitrification.