News News



Contribution of Anammox to Nitrogen Removal in Two TemperateForest Soils


Former lab member, Dr. Dan Xi published a paper entitled "Contribution of Anammox to Nitrogen Removal in Two TemperateForest Soils" on "Applied and Environmental Microbiology".

Xi D, Bai R, Zhang LM, Fang YT (2016) Contribution of Anammox to Nitrogen Removal in Two TemperateForest Soils. Applied and Environmental Microbiology 4602-4012.

Abstract: Anaerobic ammonium oxidation with nitrite reduction to dinitrogen (termed anammox) has been reported to be an importantprocess for removing fixed nitrogen (N) in marine ecosystems and in some agricultural and wetland soils. However, its importance in upland forest soils has never been quantified. In this study, we evaluated the occurrence of anammox activity in twotemperate forest soils collected from northeastern China. With15N-labeled NO3-incubation, we found that the combined potential of the N2production rates of anammox and codenitrification ranged from 0.01 ± 0.01 to 1.2±0.18 nmol N per gram ofsoil per hour, contributing 0.5% to 14.4% of the total N2production along the soil profile. Denitrification was the main pathwayof N2production and accounted for 85.6% to 99.5% of the total N2production. Further labeling experiments with15NH4+and15NO2-indicated that codenitrification was present in the mixed forest soil. Codenitrification and anammox accounted for 2%to 12% and 1% to 7% of the total N2production, respectively. Two anammox species, "Candidatus Brocadia fulgida" and "CandidatusJettenia asiatica", were detected in this study but in very low abundance (as indicated by the hzsB gene). Our results demonstrated that the anammox process occurs in forest soils, but the contribution to N2loss might be low in these ecosystems.More research is necessary to determine the activities of different N2releasing pathways in different forest soils.