长寿湖表层沉积物中磷的赋存形态及生物有效性分析

基于连续提取法对长寿湖15个采样点沉积物中磷的赋存形态进行了研究，并探讨了磷的生物有效性和评价了沉积物的污染性。结果表明：①无机磷(IP)是长寿湖表层沉积物总磷(TP) 中的主要赋存形态，平均占总磷(TP)的74.82%，有机磷(OP)只占较小部分。②无机磷(IP)中自生钙磷(Ca-P)所占比重最大，各形态磷所占比重大小依次为：Ca-P﹥Fe-P﹥Detr-P﹥Ads-P。③相关性分析表明，总磷(TP)的含量及分布主要受到无机磷(IP)的影响，无机磷(IP)受到自生钙磷(Ca-P)的控制。④长寿湖表层沉积物中潜在生物有效磷的含量为412.13～713.25μg•g-1，平均占总磷(TP)的89.98%，具有很强的释磷潜力。⑤长寿湖表层沉积物呈中度污染，应加强监测和治理。

Phosphorus Forms and Bioavailability in Surface Sediments of Changshou Lake

Forms,bioavailability and pollution of phosphorus in the surface sediments of fifteen sampling sites from Changshou Lake were analyzed by means of sequential extraction method(SEDEX).Results showed that the main form of total phosphorus(TP) in surface sediments was inorganic phosphorus(IP),which accounted for 74.82% and organic phosphorus(OP) constituted only the minor part.Among different forms of inorganic phosphorus,calcium-phosphorus(Ca-P) was the dominant forms,and the order of share of total phosphorus was:Ca-P>Fe-P>Detr-P>Ads-P.The correlation analysis among different phosphorus forms suggested that the concentrations and distribution of TP were mainly controlled by IP while inorganic phosphorus was affected by Ca-P.Biological phosphorus in the surface sediments ranged from 412.13-713.25 μg/g and occupied 89.98% of the total phosphorus,which explained that the surface sediments of Changshou Lake had a strong potential for phosphorus release.The surface sediments of Changshou Lake showed moderate pollution to which the monitoring and management should be strengthened.