桑沟湾沉积物中磷的赋存形态及生物有效性

以桑沟湾表层沉积物为研究对象,利用连续提取法对8个采样点沉积物中磷的赋存形态、含量及分布特征进行了研究,并探讨了磷的生物有效性.结果表明：①无机磷（IP）是桑沟湾表层沉积物中磷（TP）的主要形态,平均占总磷的73.33%,有机磷（OP）只占较小的比例.②无机磷中钙结合磷占的比例相对较大,平均占总磷的45.22%,是沉积物中磷的主要赋存形态,可交换磷、铁结合磷、碎屑磷占总磷的比例分别为9.92%、4.74%、13.46%.③对各形态磷的相关分析结果表明,总磷的含量及空间分布主要受有机磷的影响与控制(P<0.05),无机磷受自生钙结合磷的影响较大(P<0.01).④磷的生物有效性分析结果表明,桑沟湾表层沉积物中潜在生物有效性磷的含量为358.05～448.39 μg/g,平均占总磷的86.54%,具有很强的释磷潜力.

Forms and Bioavailability of Phosphorus in Surface Sediments from Sungo Bay

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.