景观表流湿地沉积物磷赋存形态及特征研究

Study on the Chemical Forms of Phosphorus and Features in Sediments Form Landscape Wetland

采用Hieltjes和Lijklema的连续浸提法,对用石灰作底质改良后的景观表流湿地表层沉积物进行磷形态特征的分析。结果表明:景观表流湿地表层沉积物磷的赋存形态主要为无机磷(IP),其含量占总磷(TP)含量比例的90%以上。无机磷(IP)的主要形态之一是钙镁结合磷,其含量占总磷(TP)含量比例的50%以上。主要磷形态含量排序为:Ca-P>Res-P>NaOH-P>KCl-P>NaOH-Po。石灰用作湿地底质改良剂,可以增加沉积物中钙结合磷的含量,钙结合磷短期内不参与磷循环,从而可以减少磷向上覆水的释放。

In this study,continuous extraction of Hieltjes and Lijklema was used to analyze the morphological characteristics of phosphorus in surface sediment. The sediment comes from wetland landscape that have been modified with lime. The results showed that the phosphorus in the surface sediments of the wetland landscape was mainly IP,and its content accounted for more than 90% of the TP. The Ca-P is one of the main forms of IP,and its content accounted for more than 50%. The order of phosphorus forms is:Ca-P>Res-P>NaOH-P>KCl-P>NaOH-Po. Adding lime to the sediment can increase the amount of Ca-P. The Ca-P is more stable than other phosphorus forms and thus can reduce the release of phosphorus by overlaying water.