湖泊底泥中磷的形态分布分析

目前自然水体富营养化程度越来越严重，其底泥中磷的含量也与日俱增。不同形态分布的磷在自然情况变化时表现出不同的特性，底泥中磷的形态分布对于控制水体中磷的浓度有着重要影响。本研究以五步化学分级提取法测定了12个湖泊底泥中磷的形态分布。结果表明：在底泥中与钙结合的磷较多，平均占总量的60％左右。射线衍射结果也表明12个样品中均含有较高比例的晶体钙矿物，平均含量约为49％。除了与钙结合的磷之外，其余的磷多数与铁、锰化合物相结合，其含量平均占总数的18％。黏土矿物及铝氧化物中结合的磷占总量的8％，与残余磷9％相当。松散吸附结合态的磷含量最低约占6％。研究磷的形态分布分析方法对于了解底泥中磷的形态分布以及磷在水体一底泥中的迁移转化规律有着重要意义。

Analysis of phosphorus speciation in lake sediment samples

Nowadays, the eutrophication of natural water bodies is becoming more and more serious, and as a result the phosphorus in bottom sediment increases day by day. The status of different phosphorus distributions can change with the variation of natural environmental. Distribution of phosphorus speciation in bottom sediment has important effect on controlling the concentration of phosphorus in water. The paper studied the phosphorus speciation in bottom sediment samples of 12 lakes by using five steps sequential extraction. The experimental results indicated that phosphorus combined with calcium accounts for 60% of the total phosphorus in average. X - Ray diffraction analysis on the sediment proved that there is high content of crystallized calcium minerals in all 12 samples, witch accounted for 49% in average. Besides phosphorus combined with calcium, a part of phosphorus is bounded to chemical compound of iron and manganese, contributes for 18% to the total phosphorus in average. Phosphorus bounded by aluminum and clay minerals contributes 8% , which is similar to the 9% residue phosphorus. The least phosphorus loosed sorbed one, which is 6% in average. The method of study on phosphorus speeiation has important significance for understanding the phosphorus speeiation in bottom sediment and he migration and transformation principles of phosphorus between water body and bottom sediment.