The nature of organic phosphorus in marine sediments: New insights from 31P NMR

Abstract

Different classes of organic phosphorus compounds have been identified in marine sediment samples taken at depth in cores from pelagic, lower slope, and continental shelf depositional environments using solution and solid-state magic angle spinning (MAS) 31P nuclear magnetic resonance (NMR) techniques. Phosphate esters have been identified as the major form of organic phosphorus in all sediment extracts and in separated bulk organic matter. Phosphonates, a form of organic P previously unreported in marine sediments, were identified in all but one of the samples. The persistence of both phosphate esters and phosphonates at depth in sediment cores suggests that these compound classes include undegradable forms of organic phosphorus that represent an important sink for phosphorus in the ocean.