Soil ammonia-oxidizing archaea in a paddy field with different irrigation and fertilization managements

Because ammonia-oxidizing archaea (AOA) are ubiquitous and highly abundant in almost all terrestrial soils, they play an important role in soil nitrification. However, the changes in the structure and function of AOA communities and their edaphic drivers in paddy soils under different fertilization and irrigation regimes remain unclear. In this study, we investigated AOA abundance, diversity and activity in acid paddy soils by a field experiment. Results indicated that the highest potential ammonia oxidation (PAO) (0.011 μg NO 2 - –N g -1 d.w.day -1 ) was found in T 2 (optimal irrigation and fertilization)—treated soils, whereas the lowest PAO (0.004 μg NO 2 - –N g -1 d.w.day -1 ) in T 0 (traditional irrigation)- treated soils. Compared with the T 0 —treated soil, the T 2 treatment significantly ( P