扰动与钝化剂对水/沉积物系统中磷释放及磷形态的影响

Effect of perturbance and inactivaton agent on the phosphorus release and phosphorus forms from sediment

考察了扰动与钝化剂对滇池重污染底泥的磷释放的影响．结果表明，钝化剂（PAM＋聚铝）有显著的抑制沉积物的磷释放和捕捉上覆水中含磷颗粒的效果．加钝化剂后，上覆水的总磷（TP）、溶解性总磷（DTP）和溶解性无机磷（DIP）分别比未加钝化剂组低50．0％-89．8％，85．5％～97．9％和96．5％-100．0％．扰动促进了沉积物的磷释放，这是因为扰动导致泥水混合程度增加；扰动导致沉积物氧化还原状态的改变．5d后扰动组的磷开始释放，而未扰动组在第52d仍未释放．沉积物中释放的磷主要是磷酸盐．扰动促进了DIP的释放，扰动后DTP／TP、DIP／DTP及DIP／TP均增加．投加的铝盐的量在试验期间导致的上覆水中残余铝的含量在安全范围内．扰动对上覆水中残余铝的含量影响不大．

The influence of perturbance and inactivatim agent on the release of P from sediment of Lake Dianchi was studied. The inactivation agent had significant effect on the restrain of P release from the sediment and the catch of particles including P in the overlying water. The totle phosphorus （TP）, dissolved totle phosphorus （DTP） and dissolved inorganic phosphorus （DIP） content in the overlying water with inactivation agent addition were 50.0%-89.8%, 85.5%97.9% and 96.5%-100.0% lower than the control set. Perturbance accelerated the release of P from sediment. One possible reason was the perturbance increased the mixture of sediment and water, another reason was the perturbance caused the variation of oxidation-reduction status of sediment. P release became obvious after 5 days of perturbance set （with 300r/min, 4h/d）, while the control set did not release P until 52 days. The major form of P released from sediment was phosphate. Perturbance accelerated the release of DIP, the DTP/TP, DIP/DTP and DIP/TP all increased after the perturbance. The residuum aluminum concentration caused by the addition of aluminum in the overlying water located in the safe region. Perturbance had few affect on the residuum aluminum concentration in the overlying water.