A bacterium(designated strain Y1) degrading acetanilide herbicide mefenacet was isolated from aerobic sludge. Based on the analyses of partial 16S rRNA gene, cellular fatty acid and BIOLOG-GN, and general physiologica...A bacterium(designated strain Y1) degrading acetanilide herbicide mefenacet was isolated from aerobic sludge. Based on the analyses of partial 16S rRNA gene, cellular fatty acid and BIOLOG-GN, and general physiological and biochemical characteristics, strain Y1 was identified as Sphingobacterium multivolum. Strain Y1 was able to degrade mefenacet used as sources of carbon and energy. Degradation of mefenacet was accompanied by producing the metabolites N-methylaniline and an unidentified compound with molecular weight 205, indicating a metabolic pathway of mefenacet initiated by hydrolysis of amido bond.展开更多
The characteristics of methane emission were compared among six types of upland and paddy soils developed from different parent materials with distinct physics and chemical properties after planting rice. The fluxes o...The characteristics of methane emission were compared among six types of upland and paddy soils developed from different parent materials with distinct physics and chemical properties after planting rice. The fluxes of methane emission in submerged soils from the upland were obviously lower than those from the paddy rice field. The flux of methane emission in the paddy soil developed from fluvo-aquic soil was the largest among all the types of soils. Planting of rice was helpful to emission of methane in soils. The amounts of various groups of methanogenic flora were conformed with the deferences among the fluxes of methane emission in various types of soils. Methane formation was observed in each type Of air-dried soils stored for a long time after addition of water and incubation at 35℃.展开更多
Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativ...Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativa >C. difformis, with the former two 11 and 8 times as much as that of the latter, respectively. And it was just opposite tothat of the methane-forming activities of roots of the three plants. The diurnal changes of methane emission of thethree plants were relatively consistent with valleys during 11:00-14:00 and midnight and peaks during 8:00-11: 00,14:00- 20:00 and about 5:00 early morning. The methanogenic activites in rhizospheric soils were higher than those innonrhizospheric soils with P. crus-galli and O. sativa, but not with C. difformis. The pathways of methane release ofP. crus-galli and O . sativa were probably through the top gaps near the junctions of nodal plate and leaf sheath, how-ever in C. difformistopgaps from which methane could escape into atmosphere were not found.展开更多
文摘A bacterium(designated strain Y1) degrading acetanilide herbicide mefenacet was isolated from aerobic sludge. Based on the analyses of partial 16S rRNA gene, cellular fatty acid and BIOLOG-GN, and general physiological and biochemical characteristics, strain Y1 was identified as Sphingobacterium multivolum. Strain Y1 was able to degrade mefenacet used as sources of carbon and energy. Degradation of mefenacet was accompanied by producing the metabolites N-methylaniline and an unidentified compound with molecular weight 205, indicating a metabolic pathway of mefenacet initiated by hydrolysis of amido bond.
文摘The characteristics of methane emission were compared among six types of upland and paddy soils developed from different parent materials with distinct physics and chemical properties after planting rice. The fluxes of methane emission in submerged soils from the upland were obviously lower than those from the paddy rice field. The flux of methane emission in the paddy soil developed from fluvo-aquic soil was the largest among all the types of soils. Planting of rice was helpful to emission of methane in soils. The amounts of various groups of methanogenic flora were conformed with the deferences among the fluxes of methane emission in various types of soils. Methane formation was observed in each type Of air-dried soils stored for a long time after addition of water and incubation at 35℃.
文摘Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativa >C. difformis, with the former two 11 and 8 times as much as that of the latter, respectively. And it was just opposite tothat of the methane-forming activities of roots of the three plants. The diurnal changes of methane emission of thethree plants were relatively consistent with valleys during 11:00-14:00 and midnight and peaks during 8:00-11: 00,14:00- 20:00 and about 5:00 early morning. The methanogenic activites in rhizospheric soils were higher than those innonrhizospheric soils with P. crus-galli and O. sativa, but not with C. difformis. The pathways of methane release ofP. crus-galli and O . sativa were probably through the top gaps near the junctions of nodal plate and leaf sheath, how-ever in C. difformistopgaps from which methane could escape into atmosphere were not found.
