Methane emission from rice fields at Cuttack, India. uri icon

abstract

  • Methane (CH4) emission from rice fields at Cuttack (State of Orissa, eastern India) has been recorded using an automatic measurement system (closed chamber method) from 1995-1998. Experiments were laid out to test the impact of water regime, organic amendment, inorganic amendment and rice cultivars. Organic amendments in conjunction with chemical N (urea) effected higher CH4 flux over that of chemical N alone. Application of Sesbania, Azolla and compost resulted in 132, 65 and 68 kg CH4 ha(-1) in the wet season of 1996 when pure urea application resulted in 42 kg CH4 ha(-1). Intermittent irrigation reduced emissions by 15% as compared to continuous flooding in the dry season of 1996. In the wet season of 1995, four cultivars were tested under rainfed conditions resulting in a range of emissions from 20 to 44 kg CH4 ha(-1). Application of nitrification inhibitor dicyandiamide (DCD) inhibited while Nimin stimulated CH4 flux from flooded rice compared to that of urea N alone. Wide variation in CH4 production and oxidation potentials was observed in rice soils tested. Methane oxidation decreased with soil depth, fertilizer-N and nitrification inhibitors while organic amendment stimulated it. The results indicate that CH4 emission from the representative rainfed ecosystem at the experimental site averaged to 32 kg CH4 ha(-1) yr(-1).

publication date

  • 2000
  • 2000