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Updated: May 18, 2026
10:49
Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
Phosphorus flux from wetland ditch sediments
1Department of Geography and Environmental Science, School of Human and Environmental Sciences, The University of Reading, Berkshire RG6 6DW, UK.
The Science of the Total Environment
|September 8, 2012
Summary
Agricultural land use contributes to phosphorus (P) accumulation in drainage ditch sediments, posing an ecological threat. This study quanties P forms and internal loading, revealing significant P flux from sediment to water, especially near drainage entry points.
Area of Science:
- Environmental Science
- Ecology
- Soil Science
Background:
- Phosphorus (P) accumulation in drainage ditch sediments threatens aquatic ecosystems.
- Ditch management varies between wetland restoration and agricultural drainage.
Purpose of the Study:
- To investigate P amounts, forms, and internal loading in ditch sediments.
- To evaluate P diffusive flux and redox conditions in sediment-porewater.
- To correlate sediment P characteristics with P flux.
Main Methods:
- Chemical fractionation to characterize sediment-bound P forms and mobility.
- In situ pore-water equilibrators to measure diffusive P flux.
- Analysis of sediment P saturation and NaOH-extractable P.
Main Results:
- Sediment pore-water profiles showed reducing conditions with depth, indicating net P flux from sediment to water.
- P flux values ranged from 0.33 to 1.30 mg m(-2) day(-1).
- Degree of P saturation and Fe/Al-bound P significantly correlated with P flux.
Conclusions:
- Both historical and ongoing agricultural land use contribute to elevated P levels in ditch sediments.
- Proximity to agricultural drainage entry points showed the highest P flux.
- Ditch sediment P status is influenced by surrounding land management practices.
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