Methane Oxidation and Nitrogen Transformations in Gray Forest Soil

摘要

The samples of gray forest soil,taken from arable sites and from under a forest,were incubated under low (0.0006%) and increased (0.06,0.6,and 6%) methane concentrations in the atmosphere.The oxidation rate of methane concentrations close to the atmospheric level comprised 0.024-0.51 ng CH_4/g soil per hour in the arable soil and 0.21-0.41 ng CH_4/soil per hour in the forest soil.The oxidation of increased methane concentrations occurred after a lag-period of 180 h in arable soils to 200-250 h in the soil under the forest.The application of (NH_4)_2SO_4 at a rate of 6 mg N/100 g decreased by 12-62% the activity of atmospheric methane oxidation in arable soil and did not affect the methane-oxidation activity of forest soil.The inhibiting effect of N-NH_4 on the oxidation of increased methane concentrations was insignificant.It is demonstrated that the increase of methane concentrations to 0.06% stimulated nitrogen mineralization and nitrification,but the intensity of these processes decresaed under a high (6%) methane content.The results of this study demonstrate a close relationship between the processes of methane oxidation in gray forest soil and nitrogen transformation.