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Updated: Jul 5, 2026
06:42
Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment
Published on: July 22, 2019
Marine polyphosphate: a key player in geologic phosphorus sequestration.
Julia Diaz1, Ellery Ingall, Claudia Benitez-Nelson
1School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332-0340, USA.
Science (New York, N.Y.)
|May 3, 2008
Summary
Marine sediment calcium phosphate mineral formation, a key phosphorus sink, is explained by diatom polyphosphates. This discovery clarifies a long-standing mystery in marine geochemistry and sedimentology.
Area of Science:
- Geochemistry
- Marine Science
- Biogeochemistry
Background:
- Authigenic calcium phosphate minerals in marine sediments are a significant phosphorus sink.
- The formation mechanism of these minerals is poorly understood due to unfavorable sediment chemistry.
- Diatom-derived polyphosphates are abundant in marine environments.
Purpose of the Study:
- To elucidate the mechanism of in situ calcium phosphate mineral formation in marine sediments.
- To identify the role of diatom-derived polyphosphates in this process.
- To explain the observed dispersed distribution of calcium phosphate minerals.
Main Methods:
- High-sensitivity X-ray techniques.
- Electrodialysis.
- Analysis of marine sediment samples.
Main Results:
- Diatom-derived polyphosphates are critical for calcium phosphate mineral formation.
- A novel mechanism involving polyphosphates explains mineral precipitation.
- This mechanism accounts for the widespread, dispersed distribution of these minerals.
Conclusions:
- Polyphosphates from diatoms drive calcium phosphate mineral formation in marine sediments.
- This finding resolves a fundamental mystery in marine geochemistry.
- The proposed mechanism explains a key biogeochemical process impacting phosphorus cycling.
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