Fractionation and Bioavailability of Phosphorus and Its Relation to Chlorophyll-<i>a</i> at the Coastal Area of Semarang City

Abstract We investigate the distribution of various fractions phosphorus (P) in sediments at coastal area Semarang City. Samples were collected from thirteen locations Banjir Kanal Barat, port and Timur. Sedimentary parameters such as sand, silt, clay, organic carbon analysed order to find out their relation with P fractions. The sediment types are predominantly sandy silty low clay content. Among all (loosely bound/Ads-P), bound calcium/Ca-P), iron bound/Fe-P), fraction/OP), Ca-P constitute largest portion (71.2 %) followed by iron-bound (17.0 %), fraction (10.4 loosely (1.4 %). bioavailable range 20.2 % 42.0 total (TP) content average 28.8 %. Relatively high Ads-P is observed offshore comparatively mud percentage compared near-shore locations. abundance main forms surface follows: &gt; Fe-P OP Ads-P. concentration this causes chlorophyll- a 9.09 21.09 mg/m 3 .