Community Characteristics Of Soil And Sediment Microbial Oxidation Of Ammonia Library Foreshore Areas Miyun Reservoir And Response Relationships With Environmental Factors

Ammonia oxidation is an important process forglobal nitrogen cycling. Both ammonia-oxidizing bacteria (AOB) and archaea (AOA) can be the important players in nitrification process. This study investigated the abundance and community structure of AOA and AOB in sediment of Miyun Reservoir and adjacent soils, and determined the key factors of environmental physical and chemical. The microscopic simulation experiment investigated the impacts of organic carbon and ammonium salt amendment on AOA and AOB abundance and composition in riparian soil. The results including:(1) The richness and diversity of AOB and AOA were lowest. The diversity of AOB in farmland soil was relatively high, while the diversity of AOA in the unplanted riparian soil was the highest. In the sediment deposition, the diversity of AOA is lower than the AOB; In the farmland soil, the diversity of AOA is higher than the AOB.(2)Quantitative PCR assays indicated that the AOB community size in agricultural soil was much larger than that in the other habitats. The highest AOA abundance occurred in unplanted riparian soil.(3) Pearson’s correlation analysis showed the AOB diversity had positive significant correlations with pH and total nitrogen, while the AOA diversity might be negatively affected by nitrate nitrogen and ammonia nitrogen.(4) Large variations in the structures of AOA and AOB were also observed among the different habitats. The abundance of Nitrosospira-like AOB species were detected in the agricultural soil and reservoir sediment.(5) Glucose application could significantly increase the AOA community size in reservoir riparian wetland soil, but only slightly raise the AOB abundance. Moreover, glucose addition significantly decreased the diversities of AOA and AOB and altered their community compositions. The obtained archaeal amoA gene sequences were not related to cultivated AOA species. Only few Nitrosospira-like sequences were found in glucose-amended soil.(6) In the same concentration of ammonium samples, the change of AOB abundance showed a trend of increase after decreases first, the change trend of AOA is gradually increased. This indicated that AOA is suitable in the low concentration of ammonium salt environment. This work could add new insights towards nitrification in aquatic and terrestrial ecosystems.