Methane formation in soil-plant systems treating wastewater as influenced by microbial populations

摘要

The present study evaluated the effect of plant species on methane (CH_4) emission and microbial populations in three types of soil-plant systems. Results showed large variation of CH_4 flux rate ranging from 1.35 to 212.61 mg CH_4 m~(-2) h~(-1) Emission peak of CH-4 occurred in July. No significant difference was found in the non-vegetation system spanning 2 years. Compared with non-vegetation, vegetation systems had much higher flux of CH_4, and obvious seasonal variation was observed. The polyculture system planted with Zizania latifolia (Z lati-folia) and Phragmites australis (P. australis) released higher CH_4 fluxes than the mono system (P. australis), reflecting that Z. latifolia growth could simulate CH_4 emission. The fluorescence in situ hybridization (FISH) results support the characteristics of CH_4 fluxes. Much higher methanotrophs amount and lower methanogens amount from the mono system than those from the polyculture system was observed indicating that Z latifolia growth may limit the oxygen transportation resulting in higher CH_4 emission. The polyculture system has the highest potential of CH_4 emission.