PPT Slide
- Because dead organisms eventually sink, substantial amounts OP are often deposited in the bottom sediments of many aquatic ecosystems.
- Insoluble meta-phosphate compounds are often formed where oxygen is abundant, the precipitates can also deposited in the sediments.
Under low oxygen (reducing) conditions these compounds go back into solution, releasing soluble PO4 which can be “regenerated” from anaerobic sediments.
- The decomposition (generally aerobic) of organic P also releases orthophosphate.
- Rooted vascular plants can also make use of both these sources of soluble P in the sediments.
interactions of oxygenated water with low oxygen sediments can result in large returns of regenerated PO4 to overlying water
deposition => regeneration=> deposition cycles
constitute an important part of the P cycle in aquatic ecosystems