阳宗海砷污染水质变化过程分析

为掌握2008年阳宗海砷（As）污染事件后控制与修复过程中水质特征及变化，对湖水As含量、pH值、电导率、总硬度等水质参数，以及底质As含量和生物残毒进行全程监测和分析评价。结果表明：阳宗海As污染事件后水质恢复历时28个月；阳宗海湖水As质量浓度经历了先上下波动、后持续下降再到稳定在0．05mg／L以下的变化过程；底泥中As的质量浓度经历了先迅速升高后大幅下降，再小幅上涨后又回落至21．5～27．0mg／L的变化过程；pH值、电导率及总硬度等参数受到一定影响，湖水中贝类等水生生物对As的富集能力较强。最后从管理角度提出了保护阳宗海水资源的措施。

Variation of water quality of Yangzonghai Lake affected by arsenic pollution

In order to investigate the variation of water quality of Yangzonghai Lake during arsenic pollution control and water quality restoration after arsenic pollution in the lake in 2008, we conducted monitoring throughout the entire process and evaluation of the water quality parameters, including the arsenic content in the lake, the pH value, conductivity, and total hardness, and the arsenic content in bottom sediment and biological residual toxin. The results show that it took 28 months for the water quality in the lake to be restored from arsenic pollution. The arsenic content in the lake fluctuated initially, then decreased continuously, and finally remained at 0.05 rag/L, while the arsenic content in bottom sediment increased rapidly at the beginning, then decreased sharply, and finally, after another slight increase, dropped back to 21.5 to 27.0 mg/L. The pH value, conductivity, and total hardness were affected to a certain extent. Aquatic organisms such as shellfish showed a remarkable accumulation of arsenic. We put forward some suggestions on the protection of water resources in Yangzonghai Lake from the point of view of management.