Premium
Effects of environmental conditions on the nitrifying population dynamics in a pilot wastewater treatment plant
Author(s) -
Lydmark Pär,
Almstrand Robert,
Samuelsson Kristina,
Mattsson Ann,
Sörensson Fred,
Lindgren PerEric,
Hermansson Malte
Publication year - 2007
Publication title -
environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.954
H-Index - 188
eISSN - 1462-2920
pISSN - 1462-2912
DOI - 10.1111/j.1462-2920.2007.01336.x
Subject(s) - biology , wastewater , sewage treatment , population , nitrifying bacteria , dynamics (music) , ecology , nitrification , waste management , demography , engineering , nitrogen , sociology , physics , quantum mechanics , acoustics
Summary The effect of environmental conditions, especially ammonium concentration, on community composition and nitrification activity of nitrifying bacterial biofilms in a pilot wastewater treatment plant was examined. A decreasing ammonium gradient was created when four aerated tanks with suspended carrier material were serially fed with wastewater. Community composition was analysed using fluorescence in situ hybridization (FISH) probes as well as partial 16S rRNA and amoA gene analysis using polymerase chain reaction‐denaturating gradient gel electrophoresis (PCR‐DGGE) and sequencing. Fluorescence in situ hybridization probes identified at least five ammonia‐oxidizing bacterial (AOB) and two nitrite‐oxidizing bacterial (NOB) populations. A change in nitrifying community was detected in the tanks, indicating that ammonium was an important structuring factor. Further, we found support for different autoecology within the Nitrosomonas oligotropha lineage, as at least one population within this lineage increased in relative abundance with ammonium concentration while another population decreased. Absolute numbers of AOB and NOB growing in biofilms on the carriers were determined and the cell specific nitrification rates calculated seemed strongly correlated to ammonium concentration. Oxygen could also be limiting in the biofilms of the first tank with high ammonium concentrations. The response of the nitrifying community to increased ammonium concentrations differed between the tanks, indicating that activity correlates with community structure.