Abstract
Ammonia oxidation has been intensively studied for its sensitivity to environmental shifts and stresses. However, acute stress effects on the occurrence and composition of ammonia oxidizing bacteria (AOB) and archaea (AOA) based on expression of related molecular markers in complex soil environments have been to an extent overlooked, particularly concerning transient but commonly occurring environmental changes like soil moisture shifts. The present study investigates the responses of AOB and AOA to moisture shifts and high Zn soil content. AmoA gene copies and transcripts of AOB and AOA along with potential nitrification activity were measured in a soil microcosm approach for investigating the referred environmental shifts. Moisture change from 87 to 50 % of the water holding capacity caused a ~99 % reduction of AOB but not of AOA amoA transcripts that did not change significantly. Increasing applied zinc concentrations resulted in a reduction of potential nitrification rates and negatively affected studied gene expressions of both AOB and AOA, with AOB being more responsive. Both 16 S rRNA and amoA transcripts of AOB had an inverse relation to the applied zinc, indicating a gradual loss in total cell activity. Our results suggest the existence of pronounced differences between AOB and AOA concerning ammonia oxidation activity.
Original language | English (US) |
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Pages (from-to) | 1028-1037 |
Number of pages | 10 |
Journal | Microbial ecology |
Volume | 64 |
Issue number | 4 |
DOIs | |
State | Published - Nov 2012 |
Externally published | Yes |
Bibliographical note
Funding Information:The present study was carried out as part of the GEBEP project funded by the Cariplo Foundation (Italy) and was also supported by the Doctoral School on the Agro-Food System (Agrisystem) of the Università Cattolica del Sacro Cuore (Italy).
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Ecology
- Soil Science