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Exploited gasfields and underground gasholders are specific sources of increasing concentration of methane.Methane migrates into the soils by diffusion and convection through natural and technogenic cracks in geological structures,and influencing on soils functioning.Soil cover of gas-bearing area functions as specific bilateral,periodically penetrating geomembrane.Soils shield,transform and differentiate migrating fluxes of technogenic-allochthonous methane.Methanes interaction with soils air consists in its ascending (descending) and lateral diffusion and convection in soils.Methane fluxes dissipate in porous space of soils,forming gas anomalies.The technogenic-allochthonous methane concentration strongly varies in soils air on gas-bearing area (1-10000 ppm),on average exceeds autochthonous microbiologically produced methane.Migratory methane is deposited on diffusion and sorption barriers.The capacity of diffusion barrier depends on effective coefficient of diffusion,the attitude of air and general porosity,granulometric composition and sharply differs in automorphic,semi-hydromorphic and hydromorphic soils reaching maximum in hydromorphic,and among the soils with identical water content-in heavy soils.The capacity of sorption barrier is defined by abiotic methane absorption and specific surface of soils and grows with their increasing in soils with heavier granulometric composition or in soils with peat and gleic horizons.The low sorption capacity promotes increase of methane concentration in soils air and decreases its utilization by microorganisms which quantity depends on sorpfion properties.The central component of functioning that promotes a number of essential transformations in soils on gas-bearing areas is methane interaction with biotic phase.The periods of methane deposition by diffusion and sorption barriers are used for biological methane oxidation and formation of biogeochemical barriers in soils.The activity of bacterial methane oxidation is characterized by spatial variability and depends on entering of methane,defined by granulometric composition,soils moisture,the attitude of air and general porosity,Eh,organic matter content,salinization.Calculations of mass balance have shown,that fluxes of natural gas are spent on:bacterial oxidation (99-90 %),as a result about 68 % of methanes carbon assimilates in biomass of methano(methylo)trophic bacteria,32 % emits as C02,and methane emission to the atmosphere (1-10 %).CO2 emission on gas-bearing areas exceeds its natural emission in south-taiga and steppe zones,increasing its concentration in the atmosphere.Oxidation of technogenic-allochthonous methane in soils of gas anomaly is average in 22 times higher then autochthonous,with the greatest excess in summer period.Soils bacterial oxidation oftechnogenic-allochtonous methane is absent in spring,but in summer and autumn its exceeds emission accordingly on 2 and 1 order.Emission of technogenic-allochthonous methane at normal compression of gas is higher on the order and at reduced compression is equal to emission of autochthonous.The maximal contribution to methane emission to the atmosphere gives spring period,minimal-summer.Soils absorption of atmospheric methane is 30-70 % of its emission.During interaction between technogenic-allochthonous methane and soil on diffusion,sorption and biogeochemical barriers occurs its transformation,accompanied by strengthening of variability of oxidation-reduction potential and formation of pedogenic bacteriomorphic nanodispersic magnetic oxides of iron.