Spatial Distribution and Factors Shaping the Niche Segregation of Ammonia-Oxidizing Microorganisms in the Qiantang River, China

• DOI: 10.1128/aem.00543-13
• Publication Date: 2013-04-27T01:27:43Z
• Authors: Shuai Liu; Lidong Shen; Liping Lou; Guangming Tian; Ping Zheng; Baolan Hu
• Keywords: 0301 basic medicine; China; Geologic Sediments; 0303 health sciences; Bacteria; Base Sequence; Molecular Sequence Data; Sequence Analysis, DNA; Hydrogen-Ion Concentration; 15. Life on land; Real-Time Polymerase Chain Reaction; Archaea; Carbon; 6. Clean water; 03 medical and health sciences; Rivers; Species Specificity; Ammonia; 13. Climate action; Cluster Analysis; 14. Life underwater; Cloning, Molecular; Oxidation-Reduction; Phylogeny; Demography

ABSTRACT

Ammonia oxidation is performed by both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). However, the current knowledge of the distribution, diversity, and relative abundance of these two microbial groups in freshwater sediments is insufficient. We examined the spatial distribution and analyzed the possible factors leading to the niche segregation of AOA and AOB in the sediments of the Qiantang River, using clone library construction and quantitative PCR for both archaeal and bacterial amoA genes. pH and NH 4 + -N content had a significant effect on AOA abundance and AOA operational taxonomy unit (OTU) numbers. pH and organic carbon content influenced the ratio of AOA/AOB OTU numbers significantly. The influence of these factors showed an obvious spatial trend along the Qiantang River. This result suggested that AOA may contribute more than AOB to the upstream reaches of the Qiantang River, where the pH is lower and the organic carbon and NH 4 + -N contents are higher, but AOB were the principal driver of nitrification downstream, where the opposite environmental conditions were present.