太原市引黄供水体系水体富营养化调查

Investigation on eutrophication of water-supplying system from Yellow River diverting into Taiyuan

目的调查山西省太原市引黄供水体系藻类污染状况。方法分别于2006年5月从万家寨水库、呼延水厂入厂水和出厂水、管网末梢4个环节采集水样,检测总氮(TN)、总磷(TP)、叶绿素-a(Chla)、微囊藻毒素-LR(MC-LR)含量和藻细胞总数,评价其富营养化和藻类污染状况。结果万家寨水库总氮(3.921 mg/L),总磷含量(0.145 mg/L)均高于地面水环境质量标准III级标准(GB383-2002,TN 1.0 mg/L,TP 0.05 mg/L);叶绿素-a含量为2.389μg/L,藻细胞数达到150×104个/L,MC-LR含量为0.945μg/L,未超过生活饮用水质中MC-LR限值(1μg/L)。呼延水厂入厂水除总磷(0.029 mg/L)低于地面水环境质量标准III级标准外,其余各项指标与万家寨差别不明显。出厂水和管网水中的藻细胞数和MC-LR含量均比入厂水有明显减少,未检测到叶绿素-a,但管网总氮、总磷含量比出厂水增高。结论万家寨水库呈现富营养化,有较多藻类污染。出厂水和管网水中存在较高总氮和总磷污染。

Objective To investigate the algae pollution of water- supplying system from Yellow River diverting into Taiyuan. Methods Water samples were collected in Wanjiazhai reservoir, the entrance of Huyan water plant, the exit of Huyan water plant and strainer endings. The eutrophic level and algae pollution of the water - supplying system were evaluated through measuring total nitrogen（TN） concertration, total phosphorus（TP） concertration, chlorophyll-a level（Chla）, microcystin-LR（MC-LR） level and total amount of the algal cells. Results Both TN concertration（3.921 mg/L） and TP concertration（0.145 mg/L） in Wanjiazhai reservoir exceeded the standard Ⅲ（TN1.0 mg/L, TP 0.05 mg/L） of GB3838- 2002 （Surface Water Environment Quality Standard）. Chla level was 2. 389 μg/L. The amount of algal cells was 150 × 10^4/ L. The concentration of MC- LR was 0.945 μg/L, lower than the MC- LR limit （1 μg/L） of domestic drinking water hygienic guide. The rest indexes of the samples from the entrance of Huyan water plant were the same as Wanjiazhai reservoir, except for TP concentration which was lower than the standard Ⅲ of GB3838 - 2002 （Surface Water Environment Quality Standard）. MC-LR level and total amount of the algal cells were obviously lower for the samples of exit of Huyan water plant and strainer endings than those in the entrance of Huyan water plant. Chla was not detected. But TN and TP concentration of samples from strainer endings were higher than that in the exit of Huyan water plant. Conclusion Wanjiazhai reservoir was in eutrophication and algae pollution. TN and TP pollution appeared in the samples from the exit of Huyan water plant and strainer endings.