Archaea rather than bacteria control nitrification in two agricultural acidic soils

摘要: Nitrification is a central component of the global nitrogen cycle. Ammonia oxidation, first step nitrification, performed in terrestrial ecosystems by both ammonia-oxidizing bacteria (AOB) and archaea (AOA). Published studies indicate that soil pH may be critical factor controlling relative abundances AOA AOB communities. In order to determine contributions ammonia oxidation two agricultural acidic Scottish soils (pH 4.5 6), influence acetylene (a nitrification inhibitor) was investigated during incubation microcosms at 20 °C for 1 month. High rates were observed absence acetylene. Quantification respective amoA genes key functional gene oxidizers) demonstrated significant growth AOA, but not AOB. A positive relationship found between rate growth. inhibited acetylene-containing microcosms. Moreover, transcriptional activity decreased significantly compared with control, whereas no difference activity. Consequently, only archaeal bacterial oxidizer communities strongly suggest AOB, control these soils.