EFFECTS OF AMMONIA FERTILIZATION ON METHANOTROPHS IN LANDFILL COVER SOILS
Landfill cover soil, enriched with methanotrophs, is an important sink for the methane emitted from landfill body. The activity of methanotrophs is influenced by nitrogen fertilization contradictorily. In this study, the hypothesis whether methane oxidation rate were influenced by nitrogen fertilization through affecting the methanotrophs was investigated. To this purpose, a series of soils were incubated by amending with different mineral nitrogen solution. Through the culturing period, methanotrophic activity was analyzed by testing methane oxidation rate, as well as real-time PCR and denaturing gradient gel electrophoresis (DGGE) analysis of 16S rDNA gene fragments were performed to monitor the quantity and community structure of type Ⅰ and type Ⅱ methanotrophs. In all treatments, methane consumption increased to a peak value in the initial 20 to 30 days, then declined to a lower steady state value. Compared with the unamended control soil (11 mgCH4·kg-1 drysoil·h-1), ammonia amendment enhanced the methane oxidation potential to 20 mgCH4·kg-1 drysoil·h-1 with a lag-phase in different levels, while nitrate amendment totally inhibited the methane oxidation capacity. DGGE profile revealed that the samples with high ammonia amendment were distinct in type Ⅱ methanotrophic community from lower ammonia amended soils as extra bands (phylotypes) became visible in former samples. Additionally, the community structure of latter samples didnt vary a lot through the whole incubation period. It suggested that methanotrophs adapted to specific ammonia concentration can survive through competition in a new environment, which resulted in the variation of its abundance and community structure, and subsequently the change of methane oxidation capacity.
landfill methane oxidation ammonia stimulation
N. YANG P.J. HE F. L(U) L.M. SHAO
Institute of Waste Treatment and Reclamation, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
国际会议
北京
英文
1137-1142
2010-05-17（万方平台首次上网日期，不代表论文的发表时间）