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Updated: Jul 11, 2026
10:49
Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
Phosphorus sources for aquatic weeds: water or sediments?
Science (New York, N.Y.)
|February 29, 1980
Summary
Aquatic plants primarily absorb phosphorus from sediments, even in nutrient-rich waters. This research highlights submerged macrophytes as key players in nutrient cycling, acting as nutrient pumps in aquatic ecosystems.
Area of Science:
- Aquatic botany
- Limnology
- Nutrient cycling
Background:
- Aquatic macrophytes are crucial to lake ecosystems.
- Phosphorus availability often limits aquatic plant growth.
- The primary source of phosphorus for submerged macrophytes remains debated.
Purpose of the Study:
- To determine the main source of phosphorus for submerged aquatic macrophytes in natural settings.
- To quantify the contribution of sediments to macrophyte phosphorus uptake across different trophic states.
Main Methods:
- In situ experiments were conducted with nine common aquatic macrophyte species.
- Plants were grown in mesotrophic, mildly eutrophic, and hypertrophic bays.
- Phosphorus uptake from sediments was measured during plant growth.
Main Results:
- All studied macrophyte species sourced all their phosphorus from sediments in mesotrophic and mildly eutrophic conditions.
- Under hypertrophic conditions, sediments still supplied an average of 72% of the total phosphorus absorbed by macrophytes.
- This demonstrates a consistent and significant reliance on sediment-bound phosphorus.
Conclusions:
- Submerged aquatic macrophytes overwhelmingly depend on sediments for their phosphorus supply in natural environments.
- These plants function as significant nutrient pumps, transferring phosphorus from sediments to the open water column.
- Understanding this dynamic is critical for managing nutrient levels and eutrophication in aquatic ecosystems.
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