台风对太湖微囊藻群体大小的影响

为了解台风对太湖微囊藻群体大小及在水体中分布的影响,于2013年7月12—16日台风苏力经过太湖期间,测定并分析了风速、总氮、总磷、微囊藻群体大小和Chl-a浓度变化。结果表明,台风过程中水体中总氮和总磷浓度分别从1.33 mg·L-1和0.07 mg·L-1提高到2.70 mg·L-1和0.23 mg·L-1,48 h内微囊藻群体平均大小从32.80 μm增加到69.43 μm。此外,水体中Chl-a浓度与风速显著正相关(r=0.472,P -1)。研究表明,强风浪扰动(如台风)能够引起水体中氮磷浓度的提高,改变微囊藻在水体中的分布,并且能够促进微囊藻群体的迅速增大。

Effect of typhoon on the size of Microcystis colonies in Lake Taihu

To understand the effects of typhoons on the size and distribution of Microcystis colonies in Lake Taihu,we measured and analyzed the wind speed,total nitrogen,total phosphorous,Microcystis colony size,and Chl-a concentration when Typhoon Soulik moved across Lake Taihu from July 12,2013 to July 16,2013.The concentration of total nitrogen and phosphorous during the typhoon increased from 1.33 mg·L-1 and 0.07 mg·L-1 to 2.70 mg·L-1 and 0.23 mg·L-1,respectively,and the size of the Microcystis colony increased from 32.80 μm to 69.43 μm in 48 h.Additionally,the concentration of Chl-a in the water was significantly positively correlated with wind speed(r=0.472,P -1).These results suggested that disturbances induced by strong winds or waves(such as typhoons) increase the concentrations of total nitrogen and phosphorous,changed the distribution of Microcystis in the water,and promoted a rapid increase in size of Microcystis colonies.