RESUMEN
This study presents the distribution, seasonal variations and factors influencing phosphorus (P) forms in surface sediments from the Maowei Sea. P forms were measured using the sequential extraction (SEDEX) procedures. Inorganic P (IP) was the predominant chemical form of total P (TP). Fe-bound P (FeP) was the main IP form. Sediment particle sizes, organic matter distribution, terrestrial input and aquaculture activity were responsible for the seasonal variations of different forms of P in sediment. In summer, the average proportions of P fractions in TP followed the order of organic P (OP)â¯>â¯Fe-Pâ¯>â¯authigenic P (CaP)â¯>â¯detrital P (De-P)â¯>â¯exchangeable P (Ex-P); in winter, the corresponding order was OPâ¯>â¯Fe-Pâ¯>â¯De-Pâ¯>â¯Ca-Pâ¯>â¯Ex-P. The potential bio-available P accounted for 71.1⯱â¯4.9% and 70.6⯱â¯6.3% of TP in summer and winter, respectively. Sedimentary organic matter mainly came from land-based sources in winter.