Forms and Bioavailability of Phosphorus in Surface Sediments from Sungo Bay
桑沟湾沉积物中磷的赋存形态及生物有效性

Forms and bioavailability of phosphorus in the sediments of eight sampling sites from Sungo Bay were analyzed by means of sequential extraction method (SEDEX). RESULTS: showed that: (1) The main form of total phosphorus (TP) in sediments was inorganic phosphorus (IP), which accounted for 73.33% and organic phosphorus (OP) was only the minor part. (2) Among different forms of inorganic phosphorus, calcium phosphorus (Ca-P) was the dominant forms, accounted for 45.22% of total phosphorus while organic phosphorus, adsorbed-phosphorus (Ads-P), iron-phosphorus (Fe-P) and detritus-phosphorus (Detr-P) was 26.67%, 9.92%, 4.74% and 13.46% respectively. (3) The correlation analysis among different phosphorus forms suggested that the concentrations and distribution of total phosphorus were mainly controlled by organic phosphorus (p < 0.05), while inorganic phosphorus was affected by calcium-phosphorus (p < 0.01). (4) Bioavailable phosphorus in sediments ranged from 358.05 microg/g to 448.39 microg/g and occupied 86.54% of the total phosphorus pool.