Status of Nitrogen Pools Under Important Cropping Systems in Inceptisols and Vertisols of Northern Telangana, India

Vertisols have showed 11.58, 26.92 and 19.80 % higher amount of available nitrogen, 20.42, 36.65 and 16.72 % higher amount of total nitrogen in 0-15, 15-30 and 30-45 cm depths, respectively over inceptisols. CS1 has maintained higher amount of available nitrogen content (237 kg ha-1) followed by CS2 (219 kg ha-1) > CS4 (189 kg ha-1) > CS3 (184 kg ha-1) at surface soil (0-15 cm). In vertisols, ammonical nitrogen contributed 48.72 percent to available N, whereas in inceptisols it was 44.46%. Nitrate nitrogen content was recorded significantly higher under vertisols at 0-15 and 15-30 cm soil depths. At 30-45 cm depth inceptisols recorded significantly higher values. However, NO3-N contributed 32.52 percent towards available N in inceptisols, whereas the share was 30.33 percent under vertisols. In the soil profile, percent contribution of ammonical nitrogen to available N followed as CS1 > CS4 > CS2 > CS3 with the values 53.13, 48.26, 44.49 and 41.49 %. On the other hand, percent contribution of NO3 –N towards available N followed different order as CS4 (40.08%) > CS3 (37.42%) > CS2 (32.44%) > CS1 (20.92%).