Abstract
The author reviews research progress on marine phosphorus, the most essential bioelement after carbon and nitrogen, in particular in terms of inositol hexakisphosphate（IP6）, in sediments, which is one of the few organic phosphorus compounds identified in marine environments. In terrestrial soils, IP6and its related compounds have been analyzed and identified to be the most abundant forms of soil organic phosphorus. Application of the protocols for soil IP6 analysis to marine sediment samples, however, was extremely difficult, but finally quite low concentrations of IP6were determined in Tokyo Bay sediments. This is one small step for the identification of organic phosphorus in marine sediments, but one giant leap for understanding phosphorus cycling between land and coastal marine environments.
