[Contribution of anaerobic oxidation of methane to whole methane oxidation]

The contribution of anaerobic methane oxidation to the whole methane oxidation is investigated by monitoring the activities of anaerobic and aerobic oxidation of methane in paddy soils composed mechanically of <0.02 mm and > 0.02 mm soil granules, contained different water contents, and long-term fertilized organic manure or inorganic nitrogen, phosphorus and potassium fertilizers. The results obtained from various treated soils are relatively identical, which shows that most of the activities of anaerobic methane oxidation is obviously lower than those of aerobic methane oxidation. The contribution of anaerobic methane oxidation was generally lower than 10% of total methane oxidation in paddy soils with different treatments, however, higher than 30% in the soils emerged in water as the soils became anaerobic and methane diffused difficultly into soil, leading to lower activity of aerobic methane oxidation. The long-term fertilization has a significant effect on the activity of aerobic methane oxidation in paddy soil, with the / t / > t0.05, P < 0.05, but a slightly one with ( / t / < t 0.05, p > 0.05), leading to the obvious influence on the emission flux of methane. The contribution rates of anaerobic methane oxidation were lower from 1.31% to 4.14% in the whole methane oxidation.