METHANE BUDGET FROM PADDY FIELDS IN INDIA

Earlier measurements(1) of methane emission from rice paddy fields yie lded a low methane budget of around 3 Tg/yr for India, and was reporte d at IPCC forums(2). This low budget was based on limited data. An ext ensive national methane measurement campaign from Indian paddy fields was launched in 1991, which involved a number of scientific institutio ns and universities with the National Physical Laboratory (NPL) at Del hi operating as a nodal agency. The results obtained during this campa ign based on more than 2000 observations, covering the complete 1991 k harif(monsoon) season are reported here. The methane emission rates ra nged between -0.20 and 66 mg m(-2) hr(-1). The irrigated fields (inter mittently flooded) had the values between -0.20 and 3.6 mg m(-2) hr(-1 ) (seasonal integrated flux 0.05 to 2 g m(-2)), water logged (flooded) fields between 0.04 to 66 mg m(-2) hr(-1) (seasonal integrated flux 1 0-60 g m(-2)) and deep water regimes in the range between 1.10 and 23. 3 mg m(-2) hr(-1) (seasonal integrated flux 14 to 24 g m(-2)). The met hane budget from Indian paddies has been estimated to have an average value of 4.3 Tg yr(-1) and ranges between 2.7 and 6.4 Tg yr(-1).