Effect of different land use on activity and composition of ammonia-oxidizing bacteria in an alfisol soil

Abstract

The effects of long-term (19 years) different land use on activity and composition of ammonia- oxidizing bacteria (AOB) were detected. The result showed that the potential nitrification rate in soils (RM, NPK+RM, Mowed, Fallow) was significantly higher (P < 0.05) than the CK and NPK treatments, indicating that long-term applications of recycled manure and return by plant residue both significantly increased the activity of AOB. However, the application of NPK did not enhance soil potential nitrification because of decreased pH. Fingerprints from DGGE showed that each treatment exhibit distinctly different DGGE patterns. Non-agricultural plots showed an increase in the diversity of the AOB community compared to CK, RM and NPK treatments, implying that agricultural practices, especially tillage, have an adverse effect on the soil AOB community. A phylogenetic analysis showed that most of the DGGE bands derived from all plots belonged to Nitrosospira cluster 3. © 2011 Springer-Verlag Berlin Heidelberg.