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ORIGINAL ARTICLEBioturbation of Tubificid worms affects the abundanceand community composition of ammonia-oxidizing archaeaand bacteria in surface lake sedimentsRui Huang 1,2 & Da-Yong Zhao 1,2 & Jin Zeng 3 & Ming-Yan Tian 2 & Feng Shen 1,2 &Cui-Ling Jiang 2 & Feng Huang 2 & Zhong-Bo Yu 1,2 & Qinglong L. Wu 3Received: 31 August 2015 /Accepted: 14 January 2016 /Published online: 27 January 2016# Springer-Verlag Berlin Heidelberg and the University of Milan 2016Abstract To better understand the effects of Tubificid wormbioturbation on ammonia-oxidizing microorganisms in surfacelake sediment, sediment-water microcosms with different den-sities of Tubificid worms were constructed. Clone libraries andreal-time PCR were applied to analyze the community compo-sition and abundance of ammonia-oxidizing archaea (AOA)and ammonia-oxidizing bacteria (AOB) in surface sediments.The results suggest that bioturbation of Tubificid worms pro-mote the release of nitrogen and phosphorus in surface sedi-ment. The abundance of the bacterial amoA gene was higherthan that of the archaeal amoA gene in all groups.Nitrosopumilus (93.7 % identity) was the main AOA in allgroups, whereas no Nitrosotalea sequence was detected in thethree treatment groups. All AOB in the surface sedimentsbelonged to two populations of β-Proteobacteria subclasses,Nitrosomonas(92.7%identity)andNitrosospira(97.8%iden-tity), except those in the surface sediments of the low-densitytreatment group, which contained only Nitrosomonas.Moreover, the diversities of AOA and AOB were reduced inTubificid worms containing microcosms. In conclusion, thebioturbation of Tubificid worms affects the abundance andcommunity composition of ammonia-oxidizing microorgan-isms in surface sediments.Keywords Tubificidworm . Bioturbation . Ammoniaoxidation . SedimentIntroductionNitrification, the microbial oxidation of ammonia (NH 3 ) tonitrate (NO 3 − ) via nitrite (NO 2 − ), plays a critical biogeochem-icalroleinbothindividualecosystemsand the globalnitrogencycle (Beman and Francis 2006). During nitrification, the mi-crobialoxidationofammoniaisthefirstandrate-limitingstep,and this process has long been considered to be mediatedthrough ammonia-oxidizing bacteria (AOB) (Bothe et al.2000). However, recent environmental genomic studies havesuggested that ammonia-oxidizing archaea (AOA) are able toautotrophically oxidize ammonium to nitrite (Könneke et al.2005). AOA play a principal role in energy and material cy-cles, contributing to the biogeochemical cycle. Previous stud-ies have shown the ubiquity of AOA and their predominanceoverAOB in a broad range ofecosystems(Mincer etal. 2007;Zhang et al. 2008; Yamamoto et al. 2010; Liu et al. 2014,2015; Zhao et al. 2014, 2015). A comprehensive overviewof the global comparative distribution of AOA and AOB not-ed that AOA has greater phylogenetic richness than AOB invarious habitats (Fernàndez-Guerra and Casamayor 2012).Benthic animals affect solute transport and exchange at thesediment-water interface (SWI), both directly and indirectly,through activities such as burrowing, feeding, and ventilation(Aller 2001; Gerino et al. 2003). These biological activitiesincrease the porosity and moisture content of sediments, theRui Huang and Da-Yong Zhao contributed equally to this work.* Da-Yong Zhaodyzhao@hhu.edu.cn* Zhong-Bo Yuzyu@hhu.edu.cn1State Key Laboratory of Hydrology-Water Resources and HydraulicEngineering, Hohai University, Nanjing 210098, China2College of Hydrology and Water Resources, Hohai University,Nanjing 210098, China3State Key Laboratory of Lake Science and Environment, NanjingInstitute of Geography and Limnology, Chinese Academy ofSciences, Nanjing 210008, ChinaAnn Microbiol (2016) 66:1065–1073DOI 10.1007/s13213-016-1192-8