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Updated: Jun 6, 2026
06:42
Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment
Published on: July 22, 2019
Phosphorus transformations during decomposition of wetland macrophytes.
Alexander W Cheesman1, Benjamin L Turner, Patrick W Inglett
1Wetland Biogeochemistry Laboratory, Soil and Water Science Department, University of Florida, Gainesville, Florida, United States. CheesmanA@si.edu
Environmental Science & Technology
|November 25, 2010
Summary
Wetland leaf litter decomposition sequesters phosphorus (P) in nutrient-rich soils by forming microbial P compounds. In contrast, P sequestration is limited in nutrient-poor soils, indicating P pools are independent of litter decomposition.
Area of Science:
- Environmental Science
- Soil Science
- Microbiology
Background:
- Detrital phosphorus (P) transformation in wetlands is crucial for P cycling and soil sequestration.
- Understanding P dynamics in macrophyte leaf litter is key to predicting wetland ecosystem responses to nutrient changes.
Purpose of the Study:
- To investigate changes in phosphorus (P) forms during sawgrass and cattail leaf litter decomposition.
- To compare P sequestration in subtropical wetland soils with differing nutrient statuses.
Main Methods:
- Analysis of phosphorus forms in leaf litter of sawgrass (Cladium jamaicense) and cattail (Typha domingensis).
- 15-month decomposition study at two sites with contrasting nutrient levels in a Florida subtropical wetland.
- Comparison of P sequestration rates and P forms between nutrient-enriched and unenriched sites.
Main Results:
- Nutrient-enriched sites showed net P sequestration, with P accumulating in microbial cell-like forms (phosphodiesters, pyrophosphate).
- Unenriched sites exhibited minimal P sequestration, with P form changes limited to the loss of initial leaf litter compounds.
- P pools in nutrient-poor wetland soils were largely unaffected by heterotrophic decomposition of macrophyte litter.
Conclusions:
- Nutrient-rich conditions promote P sequestration via microbial P accumulation and potential concentration of macrophyte P.
- In nutrient-poor wetlands, soil P pools appear decoupled from macrophyte leaf litter decomposition.
- Findings impact predictions of P sequestration stability and rates in wetlands under varying nutrient loads.
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