大型水生植物对太湖底泥磷释放的影响研究

通过对太湖流域常见3种水生植物(芦苇、苦草和茭白)根部底泥及无植物底泥进行磷释放特性模拟试验,讨论了pH值(分别为5、7、12)、温度(25℃、35℃)以及好氧(DO>8.0 mg.L-1)和厌氧(DO<1.0 mg.L-1)条件对磷释放强度的影响。结果表明,pH增大、温度升高、厌氧状态均可增加底泥磷释放,pH在弱酸至中性范围内底泥释磷量较小,酸性和碱性条件都有利于磷的释放,进一步分析了其中机理。从模拟试验结果来看,水生植物能在一定程度上降低湖泊底泥的总可溶性磷(TDP)含量,减少内源性磷释放,因而可供研究种植大型水生植物修复湖泊富营养化问题参考。

Effects of Macrophytes on Release of Phosphorus from Taihu Sediments

In simulation experiments of internal phosphorus release,four sediments including three sediments with growing macrophytes(Vallisneria spiralis,Phragmites communis,Zizania latifolia(Griseb)) and a control from Taihu Lake sediments were tested at different pH,temperatures and dissolved oxygen(DO) conditions.According to the results,several conclusions were obtained: intensity of phosphorus release increased with high temperature at anaerobic condition,for both acidic and alkaline condition increased the intensity of phosphorus release.It was proved that the studied macrophytes were useful to control phosphorus release in water body.In addition,the present study also provided several references in ecological remediation of eutrophicated water.