title: A conceptual ecosystem model of microbial communities in enhanced biological phosphorus removal plants.
abstract: The microbial populations in 25 full-scale activated sludge wastewater treatment plants with enhanced biological phosphorus removal (EBPR plants) have been intensively studied over several years. Most of the important bacterial groups involved in nitrification, denitrification, biological P removal, fermentation, and hydrolysis have been identified and quantified using quantitative culture-independent molecular methods. Surprisingly, a limited number of core species was present in all plants, constituting on average approx. 80% of the entire communities in the plants, showing that the microbial populations in EBPR plants are rather similar and not very diverse, as sometimes suggested. By focusing on these organisms it is possible to make a comprehensive ecosystem model, where many important aspects in relation to microbial ecosystems and wastewater treatment can be investigated. We have reviewed the current knowledge about these microorganisms with focus on key ecophysiological factors and combined this into a conceptual ecosystem model for EBPR plants. It includes the major pathways of carbon flow with specific organic substances, the dominant populations involved in the transformations, interspecies interactions, and the key factors controlling their presence and activity. We believe that the EBPR process is a perfect model system for studies of microbial ecology in water engineering systems and that this conceptual model can be used for proposing and testing theories based on microbial ecosystem theories, for the development of new and improved quantitative ecosystem models and is beneficial for future design and management of wastewater treatment systems.
authors: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 49, DK-9000 Aalborg, Denmark. phn@bio.aau.dk
authors: Per Halkjaer
authors: PH
authors: Nielsen
authors: Artur Tomasz
authors: AT
authors: Mielczarek
authors: Caroline
authors: C
authors: Kragelund
authors: Jeppe Lund
authors: JL
authors: Nielsen
authors: Aaron Marc
authors: AM
authors: Saunders
authors: Yunhong
authors: Y
authors: Kong
authors: Aviaja Anna
authors: AA
authors: Hansen
authors: Jes
authors: J
authors: Vollertsen
mesh_terms: D001419:Bacteria / Q000254:growth & development* / Q000378:metabolism; D001673:Biodegradation, Environmental; D044822:Biodiversity; D017753:Ecosystem; D008954:Models, Biological; D010758:Phosphorus / Q000302:isolation & purification*
chemical_list: D010758:Phosphorus