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Updated: Jul 20, 2026
06:42
Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment
Published on: July 22, 2019
Variability of the colloidal molybdate reactive phosphorous concentrations in freshwaters
Montserrat Filella1, Claire Deville, Vincent Chanudet
1Department of Inorganic, Analytical and Applied Chemistry, University of Geneva, Quai Ernest-Ansermet 30, CH-1211 Geneva 4, Switzerland. montserrat.filella@cabe.unige.ch
Water Research
|September 5, 2006
Summary
Colloidal particles significantly impact phosphate speciation in freshwaters. Understanding their size, composition, and distribution is crucial for accurate phosphorus analysis.
Area of Science:
- Environmental Chemistry
- Aquatic Chemistry
- Geochemistry
Background:
- Colloidal particles influence phosphate speciation in freshwater ecosystems.
- The role of these particles is not fully understood.
- Accurate phosphorus analysis requires understanding colloidal contributions.
Purpose of the Study:
- To assess the size distribution of molybdate reactive phosphorus in freshwater samples.
- To determine the mineralogical composition of colloidal particles.
- To investigate the relationship between colloid characteristics and phosphorus speciation.
Main Methods:
- Cross-flow filtration was used to analyze molybdate reactive phosphorus size distribution.
- Single particle counter technique determined colloid size.
- Transmission electron microscopy with energy dispersive spectroscopy and selected area electron diffraction analyzed mineralogy.
Main Results:
- The percentage of colloidal molybdate reactive phosphorus varied significantly, from 3% to 26%.
- Direct comparison of colloidal phosphorus percentages was found to be misleading.
- Simultaneous determination of colloid amount, size, and mineralogy is essential for interpretation.
Conclusions:
- Colloidal particle characteristics are critical for understanding freshwater phosphorus speciation.
- Observed variations in colloidal phosphorus are numerous and site-specific.
- Integrated analysis of colloid properties provides essential insights into phosphorus dynamics.
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