We used sequential extractions to quantify different forms of particulate phosphorus (PP) in sediments along the salinity gradient of the Patuxent River estuary. About 50–90% of the PP was phosphate bound to iron oxides (Fe-P), and 8–30% was organic P (org-P). Loosely sorbed phosphate (sorb-P), detrital apatite, and authigenic plus biogenic apatite each made up ,10% of the PP. Suspended sedimen...
