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Updated: May 26, 2026
06:42
Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment
Published on: July 22, 2019
Phosphorus limitation in nitrifying groundwater filters
W W J M de Vet1, M C M van Loosdrecht, L C Rietveld
1Oasen Drinking Water Company, PO box 122, 2800 AC Gouda, The Netherlands. weren.de.vet@oasen.nl
Water Research
|January 3, 2012
Summary
Phosphorus limitation restricts nitrification in groundwater, with rates significantly decreasing below 100 μg PO4-P L(-1). Low microbially available phosphorus (MAP) levels can halt nitrification, impacting drinking water treatment processes.
Area of Science:
- Environmental microbiology
- Water treatment technologies
- Nutrient cycling in aquatic systems
Background:
- Phosphorus (P) is crucial for microbial growth and metabolic processes.
- P limitation is recognized in various aquatic environments, including drinking water systems.
- Nitrification, a key process in water treatment, can be sensitive to P availability.
Purpose of the Study:
- To investigate phosphorus limitation for nitrification in anaerobic groundwater rich in iron, ammonium, and orthophosphate.
- To adapt a bioassay for determining microbially available phosphorus (MAP) for nitrification.
- To quantify the impact of MAP on ammonia-oxidizing bacteria (AOB) activity and growth.
Main Methods:
- Adapted Lehtola et al. (1999) bioassay to measure MAP.
- Conducted standardized batch experiments with enriched mixed cultures.
- Quantified nitrite, nitrate, ATP, and AOB growth (via qPCR targeting amoA gene) across a range of MAP concentrations (0-100 μg PO4-P L(-1)).
Main Results:
- Nitrification and microbial growth were limited below 100 μg PO4-P L(-1) and nearly ceased below 10 μg PO4-P L(-1).
- A linear relationship existed between MAP and maximum nitrification rate in the 10-50 μg PO4-P L(-1) range.
- AOB growth and ATP formation correlated with ammonia oxidized; slow growth observed below 25 μg PO4-P L(-1).
Conclusions:
- Microbially available phosphorus (MAP) is a critical limiting factor for nitrification in the studied groundwater.
- Orthophosphate removal in groundwater filters can lead to P-limited nitrification.
- Stimulating nitrification in P-limited groundwater filters is achievable by adding phosphoric acid.
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