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Updated: Jan 24, 2026
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Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
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Characterization of phosphorus forms in a Eutrophic Lake, China
Fazhi Xie1, Lu Li2, Kang Song3
1State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Materials Science and Chemical Engineering, Anhui Jianzhu University, Hefei 230022, China.
The Science of the Total Environment
|May 18, 2019
Summary
Highly eutrophic Dianchi Lake
Area of Science:
- Environmental Chemistry
- Limnology
- Analytical Chemistry
Background:
- Dianchi Lake is a highly eutrophic freshwater body.
- Phosphorus is a key nutrient driving eutrophication.
- Understanding phosphorus speciation is crucial for managing lake ecosystems.
Purpose of the Study:
- To investigate the molecular composition of phosphorus in cyanobacteria, suspended matter, and surface sediments of Dianchi Lake.
- To differentiate between bioavailable and non-bioavailable phosphorus fractions.
- To elucidate the role of cyanobacteria in phosphorus cycling and eutrophication.
Main Methods:
- Solution-state 31P nuclear magnetic resonance (NMR) spectroscopy on extracted samples.
- Solid-state 31P NMR spectroscopy on non-extractable residues.
- Analysis of cyanobacteria, suspended matter, and surface sediment samples.
Main Results:
- Solution 31P NMR revealed significant orthophosphate, monoester, diester, and pyrophosphate fractions.
- Organic phosphorus distribution differed between cyanobacteria/suspended matter and sediments.
- Solid-state 31P NMR indicated substantial non-extractable organic phosphorus and polyphosphate in cyanobacteria and suspended matter.
- Surface sediments showed metal-bonded pyrophosphate and high orthophosphate.
Conclusions:
- A significant portion of biogenic phosphorus in Dianchi Lake is bioavailable.
- Cyanobacteria contribute to phosphorus regeneration through the release of organic phosphorus, polyphosphate, and pyrophosphate.
- These processes exacerbate eutrophication in Dianchi Lake.
Keywords:
EutrophicationMolecular compositionNuclear magnetic resonanceNutrientsPhosphorusSolid-state (31)PMore Related Videos
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