城市景观水体石灰控藻效应研究

Performance of lime-based algae control in urban landscape water

以上海市古华园人工湖为研究对象,通过研究其藻华消长规律,考察了不同石灰投加量对城市景观水体的控藻效应及其氮磷营养盐变化.结果表明:古华园水体中藻类生物量呈明显季节性变化.投加石灰能够抑制藻类的生长,并且藻类生长的抑制效应随石灰的投加剂量增加而增强,其中当石灰投加量由0.02 g/L增加至0.2 g/L时,藻类生长抑制率由20%提升至45%.然而,当投加剂量由0.2 g/L增至0.5 g/L时,抑制率没有明显增加.因此,综合考虑石灰的抑藻效应以及经济成本等因素,最优的石灰投加剂量为0.2 g/L.不同石灰投加剂量下水体氮磷营养盐含量整体先增加后下降,最终达到动态平衡.该研究可为城市景观水体藻类控制提供新的思路.

In this research,we studied the effect of lime dosages on algae control as well as the dynamic changes in nitrogen and phosphorus nutrients in urban landscape water based on the growth and decline of algae blooms at Guhua Park in Shanghai.The results showed clear seasonal variations in algae biomass in Guhua Park.The growth of algae could be inhibited by the addition of lime,and the inhibition performance improved with increases in lime dosage.Specifically,the algal inhibition rate ranged from 20%to 46%when the applied lime dosage increased from 0.02 g/L to 0.2 g/L.When the lime dosage increased from 0.2 g/L to 0.5 g/L,however,there was no significant increase in inhibition efficiency observed.Therefore,considering both algal inhibition efficiency and economic cost,the optimum dosage of lime is 0.2 g/L.Meanwhile,nitrogen and phosphorus nutrients in water initially increased and then decreased,reaching a final dynamic equilibrium.This study offers a new approach for algae control of urban landscape water.