Marine Polyphosphate: A Key Player in Geologic Phosphorus Sequestration

• DOI: 10.1126/science.1151751
• Publication Date: 2008-05-02T12:17:00Z
• Authors: Julia Diaz; Ellery Ingall; Claudia Benitez-N...; David Paterson; Martin D. de Jonge; Ian McNulty; Jay A. Brandes
• Keywords: Diatoms; 0301 basic medicine; Geologic Sediments; 0303 health sciences; 03 medical and health sciences; Pacific Ocean; Spectrometry, Fluorescence; Microscopy, Fluorescence; Polyphosphates; Apatites; Phosphorus; Biomass

The in situ or authigenic formation of calcium phosphate minerals in marine sediments is a major sink for the vital nutrient phosphorus. However, because typical sediment chemistry is not kinetically conducive to the precipitation of these minerals, the mechanism behind their formation has remained a fundamental mystery. Here, we present evidence from high-sensitivity x-ray and electrodialysis techniques to describe a mechanism by which abundant diatom-derived polyphosphates play a critical role in the formation of calcium phosphate minerals in marine sediments. This mechanism can explain the puzzlingly dispersed distribution of calcium phosphate minerals observed in marine sediments worldwide.