Study on Nitrogen Fractions in Some Arid Zone Soils Differentially Managed under Normal Rainfed Farming and Saline-sodic Water Use

It was found that there was increase in NO₃-N, NH₄-N, hydrolyzable-N, amino acid-N and hexosamine-N in soils irrigated with saline-sodic water. The soils under rainfed farming contained higher amount of unidentified and non-hydrolyzable-N. Na⁺ and SO₄⁻² ions in irrigation water were significantly correlated with soil amino acid and hexosamine-N fractions but negatively correlated with unidentified-N.