Seasonal effect on N2O formation in nitrification in constructed wetlands.

Constructed wetlands are considered to be important sources of nitrous oxide (N(2)O). In order to investigate the contribution of nitrification in N(2)O formation, some environmental factors, plant species and ammonia-oxidizing bacteria (AOB) in active layers have been compared. Vegetation cells indicated remarkable effect of seasons and different plant species on N(2)O emission and AOB amount.

Nitrous oxide emission from polyculture constructed wetlands: effect of plant species.

Loss of nitrogen from the soil-plant system has raised environmental concern. This study assessed the fluxes of nitrous oxide (N2O) in the subsurface flow constructed wetlands (CWs). To better understand the mechanism of N2O emission, spatial distribution of ammonia-oxidizing bacteria (AOB) in four kinds of wetlands soil were compared.

Oceanicola nanhaiensis sp. nov., isolated from sediments of the South China Sea.

A Gram-negative, non-motile, rod-shaped bacterium, strain SS011B1-20(T), was isolated from sediments of the South China Sea. Growth occurred at NaCl concentrations between 0 and 10 % and at temperatures between 10 and 37 degrees C. Strain SS011B1-20(T) contained Q-10 as the major respiratory quinone and C(18 : 1)omega7c (81.

Distribution characteristics of ammonia-oxidizing bacteria in the Typha latifolia constructed wetlands using fluorescent in situ hybridization (FISH).

A molecular biology method, fluorescent in situ hybridization (FISH), in which the pre-treatment was improved in allusion to the media of the constructed wetlands (CW), e.g. the soil and the grit, was used to investigate the vertical distribution characteristics of ammonia-oxidizing bacteria (AOB) quantity and the relation with oxidation-reduction potential (ORP) in the Typha latifolia constructed wetlands under three different loadings in summer from May to September.

Study of the characteristics of CH4 and N2O emission and methods of controlling their emission in the soil-trench wastewater treatment process.

In recent years, worldwide concern over global warming has been expressed. It has been reported that domestic wastewater and its treatment processes are sources of CH4 and N2O, designated as greenhouse gases, the reduction of which was noted to be extremely important at the Third Conference of the Framework Convention on Climate Change (Conference Of the Parties; COP3). Here we report a study of a field that has been unexplored until now: analytical evaluation of the properties of the emission of CH4 and N2O and methods of restricting their emission in soil-trench wastewater treatment processes, the use of which is spreading, mainly in developing nations.