应用大麦杆控制原水蓝藻生长的初步研究

Application of Barley straw to control the growth of cyanobacteria in local raw water

蓝藻对饮水安全有潜在威胁,但在水处理过程中很难除去。华南某地原水水塘多年来受到以假鱼腥藻类为主的蓝藻水华影响,尽管曾使用多种方法进行清除,但都只能起到应急的作用,因此需要寻求长期有效控制蓝藻生长的新方法。已有研究表明大麦杆在控制淡水藻类生长方面具有一定功效,且对环境无明显负面影响。为了解大麦杆对华南某地蓝藻,特别是假鱼腥藻类生长的影响,探讨在该地区气候条件下发挥抑藻作用所需时间和效果,为原水蓝藻控制措施的采取提供科学依据,自从2005年3月起至2005年7月,选用2个沉淀池作对比实验,实验池投入g·m-3的大麦杆,对照池不加大麦杆。研究表明大麦杆对原水中假鱼腥藻类的生长有较好的抑制作用,在该地气候条件下,最少需要一至两个月的时间,大麦杆才开始产生控藻作用。

Some filamentous Cyanobacteria are potentially harmful to the safety of drinking water, but it is difficult to remove them in the process of water treatment. In some place of South China Pseudanabaena sp. and some cyanobacteria grow awfully in raw water ponds. Despite various methods had been used to control the growth of cyanobacteria in these ponds, no one were ever found to take effect long, thus it is necessary to search for new methods. As previous studies showed that barley straw was very useful in controlling the growth of some freshwater algae and they had no negative effects to local environment and ecosystem, the aim of present study is to find out whether or not barley straw could control endemic cyanobacteria, especially Pseudanabaena sp. in local raw water, if so, how long it may take. An application of 5 g·m^-3 barley straw were made in a sedimentation pond from March 2005 to May 2005, another sedimentation pond was used as a control pond without dosage of barley straw in the same time. It showed that Barley straw began to rot away in the second month after the treatment, then inhabitation of the growth of some algae were shown. The results suggested that the application of barley straw to suppress the growth of Pseudanabaena sp.was long-lasting and effective. Under local climatic conditions, it took one to two months for barley straw to take effects.