巢湖取水口浮游藻类污染调查

Investigation on Water Pollution by Algae at Locations of Water Collection in Chaohu Lake

目的 了解合肥市以巢湖为水源的水厂取水口浮游藻类污染情况。方法 于1999年2、5、8、11月份（分别代表冬、春、夏、秋季）分别距以巢湖为水源的水厂岸边1.5km（A点）和3.0km（B点）水域采集水样进行藻类鉴定和计数。结果 以巢湖为水源的水厂取水口处水样检出浮游藻类83种,分属于8门49属;A点浮游藻种类多于B点。藻类计数年均值A点为7.024X108个/L,B点为8.205X108个/L。A、B两点水样藻类计数的变化趋势均为夏季>秋季>春季>冬季。藻类优势种为铜绿微囊藻、螺旋鱼腥藻和水华鱼腥藻。水样总氮、总磷、叶绿素α年均值分别为4.30mg/L、0.09mg/L和0.015mg/L,均超过我国暂行标准。结论 巢湖水源已严重富营养化。

Objective To understand the water pollution by algae at locations of water collection of water plant treating raw water from Chaohu Lake in Hefei. Methods Water samples were collected from the locations of water collection of water plant treating raw water from Chaohu Lake including sampling point A 1.5 km and sampling point B 3.0 km far from the bank in February, May, August and November, which representing winter, spring, summer and autumn respectively. The algae in water samples were identified and counted. Results 83 kinds of algae, belong to 8 phyla and 49 genuses, were found in water samples sampled from locations of water collection of water plant treating raw water from Chaohu Lake. More kinds of algae were found in water samples collected from sampling point A compared with those from sampling point B. The annual average total count of algae were 7.024X 108/L for water samples collected from sampling point A and 8.205X 108/ L from sampling point B. The tendency of the decreasing total counts of algae in water samples from sampling point A and sampling point B in four seasons showed the same orders: summer > autumn > spring> winter. The dominant species of algae were Microcystis aeruginosa, Anabaena spiroides and Spirulina . The annual average contents of total nitrogen, total phosphorus and chlorophyl-a were 4. 30 mg/ L, 0.09 mg/ L and 0.015 mg/ L respectively, all of which exceeded the related temporary standards in China. Conclusion The source water of Chaohu Lake had been in the state of serious eutrophication.