淀山湖富营养状态调查和湖区微囊藻毒素污染现况研究

The Current Eutrophic State and the Pollution of Microcystin-LR in Dianshan Lake District

目的了解淀山湖区水质富营养状态及微囊藻毒素-LR(MC-LR)污染情况及综合整治后的效果。方法于2008年和2009年6-9月间,对淀山湖区东、南、西、北和中心5个监测点水样进行连续监测,监测指标包括总磷(TP)、总氮(TN)、浊度、pH值、耗氧量(COD)和微囊藻毒素-LR(MC-LR)。结果淀山湖湖水的pH值为7.94,呈现弱碱性,浊度20.92度、耗氧量为5.28 mg/L。淀山湖水中TP浓度、TN浓度,分别在0.06～0.31μg/mL和0.2～6.3μg/mL之间波动,均超过GB 3838-2006《地表水环境质量标准》中Ⅲ类标准,TN/TP的范围在0～54.4之间,水中MC-LR浓度为0.0085μg/L。结论淀山湖区水体呈一定的富营养化,且存在MC-LR污染,经近年环湖综合环境治理后有所改善。

Objectives To understand the eutrophic state and the pollution of microcystin-LR （MC-LR） in Dianshan Lake district, and the effectiveness of comprehensive treatment. Methods Water samples from the East, South, West, North and Central Monitoring Stations were collected continuously from June to September during 2008 to 2009 for indicator monitoring, ：including total phosphorus （ TP）, total nitrogen （TN）, turbidity, pH, chemical oxygen demand （COD） and rrLierocystin-LR （MC-LR）. Results The lake water was weakly alkaline （pH 7.94） , the turbidity was 20.92 degrees, and chemical oxygen demand was 5.28 mg/L. The content of TP and TN was in the range of O. 06 - 0.31 μg/mL and O. 2 - 6.3 μg/mL, respectively, beyond the class Ⅲ of national standards （GB 3838 -2006, quality standards for surface water）. TN/TP was in the range of 0 - 54.4, the content of MC-LR was 0. 0085 μg/L. Conclusions Dianshan Lake district was in eutrophic state and was polluted by MC - LR. The situation has been improved through comprehensive ecological environment management in recent years.