Nitrification and Nitrifying Bacteria in the LowerSeine River and Estuary(France)

Abstract

The Achères wastewater treatment plant, located just downstream of Paris, discharges its effluents into the lower Seine River. The effluents contain large numbers of heterotrophic bacteria, organic matter, and ammonium and are a source of nitrifying bacteria. As a result, degradation of organic matter by heterotrophic bacteria and subsequent oxygen depletion occur immediately downstream of the effluent outlet, whereas nitrifying bacteria apparently need to build up a significant biomass before ammonium oxidation significantly depletes the oxygen. We quantified the potential total nitrifying activity and the potential activities of the ammonia-and nitrite-oxidizing communities along the Seine River. In the summer, the maximum nitrifying activity occurs in the upper freshwater estuary, ϳ200 km downstream of Achères. The quantities of nitrifying bacteria, based on amoA gene copy numbers, and of Nitrobacter organisms, based on 16S rRNA gene copy numbers, were correlated with the potential nitrifying activities. The species composition of ammonia-oxidizing bacteria was investigated at two sites: the Triel station just downstream from Achères (km 84) and the Seine freshwater estuary at the Duclair station (km 278). By means of PCR primers targeting the amoA gene, a gene library was created. Phylogenetic analysis revealed that the majority of the analyzed clones at both sites were affiliated with the genus Nitrosomonas. The Nitrosomonas oligotropha-and Nitrosomonas urea-related clones represented nearly 81% of the community of ammonia-oxidizing bacteria at Triel and 60% at Duclair. Two other ammonia-oxidizing clusters of the ␤ subclass of the Proteobacteria, i.e., Nitrosomonas europaea-and Nitrosospira-like bacteria, were found in smaller numbers. The major change in the ammonia-oxidizing community between the two stations along the Seine River-upper estuary continuum was the replacement of the N. oligotropha-and N. urea-related bacteria by the Nitrosospira-affiliated bacteria. Although the diversities of the ammonia oxidizers appear to be similar for the two sites, only half of the restriction patterns are common to both sites, which could be explained by the differences in ammonium concentrations, which are much lower in the upper estuary than in the river at the effluent outlet. These results imply a significant immigration and/or selection of the ammonia-oxidizing bacterial population along the continuum of the Seine River from Paris to the estuary.The Seine River downstream of Paris is greatly affected by the discharge of treated effluents from the Achères wastewater treatment plant (WWTP) (8.5 million inhabitant equivalent from Paris and its suburbs, subjected only to a secondary treatment). A typical feature of the ecological functioning of the lower Seine River is a high summer oxygen deficit immediately downstream of the Achères effluent outlet due to degradation of organic matter (18,19,48) and another depletion in the freshwater estuary due to nitrification of ammonium that is also contained in the effluent ...

Archaeal ammonia oxidizers and nirS-type denitrifiers dominate sediment nitrifying and denitrifying populations in a subtropical macrotidal estuary

“…Earlier studies have suggested that nitrite (Sahan and Muyzer, 2008) and pH (Nicol et al, 2008) may be determining factors in the niche differentiation between AOA and AOB, whereas salinity and hydrological factors have been suggested to have an influence on the structure and dominance of AOA or AOB communities (Stehr et al, 1995;Cebron et al, 2003;Francis et al, 2003;Bernhard et al, 2005;Dang et al, 2008;Mosier and Francis, 2008). This suggests that there are likely to be a number of potentially confounding environmental factors shaping ammonia oxidising communities in estuarine sediments.…”

Adverse Effects of Ammonia on Nitrification Process: the Case of Chinese Shallow Freshwater Lakes

“…Reaction mixtures were incubated for 24 h in 100 ml polyethylene bottles in the dark at 20°C (Cébron et al 2003) with 50% (v/v) air headspace (de Bie et al 2002) and addition of NH 4 + (final concentration 2 mM) or NO 2 − (final concentration 0.36 mM).…”

“…Secondly, NO 2 − was further oxidized to NO 3 − by nitrite-oxidizing bacteria (NOB) . AOA and nitrifying bacteria, including AOB and NOB, have been found in a variety of environments, such as various soils (Leininger et al 2006;Bartosch et al 2002;He et al 2007), rhizosphere (Herrmann et al 2008;Marilley and Aragno 1999), ocean water and sediments (Dang et al 2008;Kim et al 2006;Ward and Carlucci 1985), wastewater treatment plant bioreactors (Park et al 2006;Daims et al 2001;Siripong and Rittmann 2007), and freshwater ecosystems (Hatzenpichler et al 2008;Herrmann et al 2009;Cébron et al 2003;Cébron and Garnier 2005). Instead of being effectively eliminated, ammonia may accumulate in water columns especially in eutrophic lakes.…”

“…Algal uptake of NH 4 + and NO 3 − was assumed to be negligible in the dark (James and Martin 2000). The NO 2 − concentrations were determined at the beginning and end of the incubation, during which the oxidation rates were shown to be linear (Cébron et al 2003 , respectively, were determined as follows: 100 ml surface water was collected into 100 ml polyethylene bottles which had a minimal air headspace to prevent additional oxygen (O 2 ) to dissolve (de Bie et al 2002) and incubated for 24 h in the dark, at in situ temperature without any addition including substrates and inhibitors. The actual rates of ammonia and NO 2 − oxidation were estimated from Filtration was performed to differentiate between particle-associated and free-living communities (Lam et al 2004).…”

Émissions d’oxyde nitreux lors du traitement de l’azote des eaux usées de l’agglomération parisienne : état actuel et prévisions

“…Depuis les années 1990, plusieurs travaux ont montré que l'azote ammoniacal (entre 1 et 4 mg N/L) apporté par les effluents de la station d'épuration Seine Aval (Achères, ouest de Paris), est complètement nitrifié au niveau de l'estuaire fluvial lors d'un transit de 200 km en aval, diminuant relativement peu sur le cours de la basse Seine (BRION et al, 2000;CÉBRON et al, 2003;GARNIER et al, 2001GARNIER et al, , 2006. L'activité nitrifiante maximale dans l'estuaire entraîne une désoxygénation importante.…”