Nitrogen losses through leachate and its distribution.

ABSTRACT

A column experiment was conducted to elucidate information on the nitrogen losses with clay loam and sandy clay loam soil collected from the farm of UPASI, Coonoor and UPASI, Valparai respectively with 5 levels of nitrogen viz., 0, 250, 375, 500 and 625 kg ha(-1) and two different rainfall intensities viz., i1 = 40 mm hr(-1) (medium rainfall intensity) and i2 = 60 mm hr(-1) (high rainfall intensity). The losses of nitrogen fractions through leachate were analyzed for a month period. The results indicated that the nitrogen application increased the concentration of NH4-N and NO3-N in the leachate collected under both the soils. The NH4-N concentration was high in the leachate collected under sandy clay loam soil (33.99 mg l(-1)) whereas N03-N concentration was high in the leachate collected under clay loam soil (17.75 mg l(-1)). Between the rainfall intensities, the NO3-N concentration was high in the leachate collected from clay loam soil under medium rainfall intensify and the reverse trend was observed under sandy clay loam soil. The distribution of NH4-N and NO3-N was higher in the clay loam soil than sandy clay loam soil. The NH4-N content increased with increase in the depth of soil column under both the soil. The N03-N distribution followed the similar trend under sandy clay loam soil. But in the clay loam soil, the highest N03-N content was detected at 14-21 cm depth under medium rainfall intensity.