干湿交替对湖滨带不同高程沉积物磷释放的影响研究

Nfluence Study of Drying and Wetting Alternation on Different Height Sediment Phosphorus Release in the Lakeside Zone

湖水水位变化引起的湖滨带沉积物干湿交替过程显著地影响着磷的迁移转化,本文以贡湖湖滨带为对象,研究湖滨带最高水位沉积物与低位淹水沉积物对磷的吸附解吸能力及再淹水过程中磷释放量。研究发现,湖滨带高位沉积物与淹水沉积物相比黏土级颗粒含量较低,中位粒径较大,湖滨带高位沉积物对磷的吸附能力弱于淹水沉积物。淹水后湖滨带高位沉积物TP释放量高于淹水沉积物,沉积物释磷以Ca-P形态为主,随着湖滨带沉积物由高到低,Ca-P释放量逐渐下降。

The sediments drying and wetting alternation caused by changes of lake water level in the lakeside zone significantly affects the migration and transformation of phosphorus,this paper took the Gong Lake lakeside zone as the object,studied the phosphorus adsorption and desorption capacity of highest water level sediment and low flooding sediment on phosphorus,and phosphorus release amount during re-flooding process in the lakeside zone.The study found that,compared with flooding sediment,clay particle content of lakeside zone high level sediment is lower,the median particle diameter is larger,and the adsorption capacity of phosphorus in lakeside zone high sediments is weaker than the flooding sediments.After flooding,TP amount released in lakeside high sediment is higher than the flooding sediment,the formation of phosphorus released in sediment is mainly Ca-P,Ca-P emission decreases gradually with lakeside zone sediments ranging from high to low.